Habitat – Discover-Nature

The High Life, animal species

In the last blog, we investigated the conditions and constraints of living at high altitudes, generally above 10,000 feet. A few physiological adaptations listed included enhanced breathing and blood supply to get more oxygen to the body, internal temperature regulation allowing some mammals to adjust to a colder environment, and smaller plants requiring less moisture and having a short growing season.

^{Common springtail, Orchesella cincta, by Mvuijlst, Feb 2009}

^{Springtail, Isotoma caerulea, by Andy Murray, Jul 2014}

The Himalayan jumping spider, Euophrys omnisuperstes, is generally found above 22,000 feet, living among rock crevices and feeding on stray insects blown upward by rising mountain winds. The spider also feeds on springtails, Collembola, once considered an insect but now classified as a free-ranging hexapod. These tiny organisms have antifreeze compounds in their blood, enabling them to live in higher, colder habitats.

Reptiles from four lizard species have been found living in higher elevations. Two species of iguana in the genus Liolaemus live in Bolivia; a third iguana species, Liolaemus tacnae, lives in Peru; and an Asian lizard, Phrynocephalus erythrurus, lives on the Tibetan plateau. All were found between 16,000 feet and 18,000 feet, but very little is known about them since these areas are difficult to access for study.

^{Golden eagle, Aquila chrysaetos, by Giles Laurent, Dec 2021; Andean condor, Vultur gryphus, by Bastihitzi, May 2013; Alpine chough, Pyrrhocorax graculus, by Jim Higham, 2008}

Birds can be found living near mountain tops year-round. The Alpine chough, Pyrrhocorax graculus, lives in social flocks from the Alps to the Himalayas. Standing 15″ high with a 30″ wingspan, they have black feathers with distinct yellow beaks and red legs. They eat insects and berries in summer, but have become well-adapted to scavenging in winter, especially around ski resorts. The Andean condor, Vultur gryphus, another social bird, roosts on cliffs and outcrops above 16,000 feet. The steep terrain provides additional protection from potential predators. Golden eagles, Aquila chrysaetos, are found world-wide in many habitats. In the mountains, they hunt marmot, hare, and young goats at lower elevations, but nest in eyries, large cliff-hugging nests at higher elevations. With wingspans up to seven feet, they can dive at speeds of up to 150mph over unsuspecting prey.

^{Left top to bottom: Common crane, Grus grus, by Savithri Singh, Feb 2020; Whooper swan,Cygnus cygnus, by KyoichiNarukami, Japan, Jan 2012; Bar-headed goose, Anser indicus, by J.M.Garg, India, Mar 2000; Ruppell’s Griffon Vulture, Gyps rueppellii, by Lip Kee, Kenya, Aug 2008}

High altitude bird species with physiological adaptations for breathing and blood supply include those whose migration routes take them over the world’s highest mountain ranges. Ruppell’s Griffon Vulture, Gyps rueppellii, with an 8-foot wingspan, has been observed at altitudes exceeding 36,000 feet over the Ethiopian Highlands of Central Africa. The common crane, Grus grus, lives across eastern Europe and northern Asia, migrating over the Alps to Africa, India and southern China. The bar-headed goose, Anser indicus, and the whooper swan, Cygnus cygnus, both live in south Asia and migrate over the Alps to central and sub-Arctic Asia to breed.

^{Above: Large-eared pika, Ochotona macrotis,}
^{by Karunakar Rayker, Ladakh India, Feb 2008}

^{Right: Snow leopard, Panthera uncia, by Vassil, Aug 2007}

The heights of the Himalayas support mammals that can concentrate their hemoglobin and allow the blood to carry more oxygen, avoiding issues with hypoxia, a shortage of usable oxygen in the body. Species with this physiological adaptation include large-eared pika, Ochotona macrotis, living above 7,700 feet up to 20,000 feet; wild yak, Bos mutus, which have larger heart and lungs than domesticated yaks; and the snow leopard, Panthera uncia, living above 3,000 feet up to 18,000 feet. The snow leopard has short, heavily furred limbs and a long, heavy tail for use as a blanket. Its large nasal cavity and strong chest allows more oxygen to be taken in with each breath.

^{Ethiopian wolf, Canis simensis, by Charles J. Sharp, Ethiopia, Dec 2017; Mountain goat, Oreamnos americanus, by Darklich14, Colorado, Aug 2009; Tibetan argali, Ovis ammon, by DonArnold, Jurica-Suchy Nature Museum, Mar 2026; Guanaco, Lama guanicoe, by Charles J. Sharp, Chile, Oct 2025; Yellow-rumped leaf-eared mouse, Phyllotis xanthopygus, drawing by Charles Darwin, 1832}

Mountain goats, Oreamnos americanus, can climb steep cliff faces with hooves that grip ledges and rock surfaces in the Rocky Mountains. The yellow-rumped leaf-eared mouse, Phyllotis xanthopygus, feeds on grains, seeds, roots, and insects in the Andean Mountains of Chile, living at altitudes to 22,000 feet. Guanaco, Lama guanicoe, a member of the camel family, lives in the Andes up to 13,000 feet and has about four times as many red blood cells as a human does. The Ethiopian wolf, Canis simensis, is an endangered species living up to 15,000 feet in central Africa with populations fragmented by pressure from human farming activities. Tibetan argali, Ovis ammon, is a wild sheep found in the Altai Mountains of Mongolia up to 19,000 feet. The ewes and lambs prefer steep, treacherous slopes as protection against predators.

Scientists continue to study species in these habitats to learn more about their specific adaptations and survival abilities in a harsh environment. You can learn more by visiting zoos or nature museums near you to investigate these fascinating species.

The High Life

Mountainous regions with high altitude habitats, generally defined as those found above 10,000 feet, are found in only a few places around the world. They include the Tibetan plateau and Himalayas in Asia, the Andean Altiplano in South America, the Ethiopian Highlands of Central Africa, the Rocky Mountains in western North America, and the Haleakala Mountains of Hawaii. High altitude regions have common characteristics that provide an array of challenges for the plant and animal species that live there.

_{Ethiopian Highlands by Martino’s doodles}

Air is composed of several gases including oxygen which makes up a consistent 21% of it. Barometric pressure is a measurement of the weight of the atmosphere above, and with more weight pressing down, air molecules are more compacted together. As one ascends, the pressure decreases with the result being that the air is thinner, less compacted, breathing becomes more difficult with less oxygen entering the lungs for every breath taken. About 3% of available oxygen is lost for every 1,000 feet of elevation gain. At 10,000 feet, there is 30% less oxygen available to breathe.

_{Haleakala Mountains by Kent Buckingham, Jul 2005}

As one ascends, along with thinning atmosphere, the temperature decreases by 4^◦Ffor every 1,000 feet, and may decrease even faster in drier air. At 10,000 feet, the average temperature is 40^◦F lower than at sea level in the same region, resulting in cool summers and frigid winters. Snow may cover these areas for much of the year, but many higher mountain peaks are too dry for snow. Vegetation is shorter, smaller in size, and slower growing. The tree-line defines a point where tress cannot survive the lower temperatures and general lack of moisture of higher altitudes.

_{Rocky Mountain National Park by Jim & Robin, Aug 2012}

When animals or humans who normally live in lower altitudes venture higher, they often experience acclimatization issues – changes in bodily functions that occur for short periods while at a higher altitude. As an example, one may experience difficulty breathing as air becomes thinner, and this strain eases after several minutes or hours. However, these changes occur every time a person ascends to those elevations. Permanent changes, which we call physiological adaptation, are known in relatively few animal species.

_{The Canapa Lagoon on the Andean Altiplano by Elias Rovielo, Feb 2019}

Physiological adaptations in birds include altered hemoglobin genes, allowing more oxygen to be carried in each molecule of blood. Birds optimize the process of getting oxygen into their blood as air moves across breathing surfaces during both inhalation and exhalation. High altitude fliers have larger hearts providing increased blood volumes for every heartbeat. In addition, they have more capillaries than other bird species, so oxygen-rich blood has to travel a shorter distance in the body to reach muscles, increasing the ability to maintain energy and movement in an efficient manner.

Mammals create their own body heat and maintain a consistent internal temperature through regulation of heat gained from burning calories and heat lost through layers of hair to the external environment. Many species living permanently in higher altitudes are able to decrease their body temperature for long periods, making it easier to adjust to a colder environment. Some species have a higher percentage of fat cells containing carbohydrates that can be called upon for extra energy for short periods.

_{The Tibetan Plateau by Tony Phillips, Aug 2006}

Typical plant life in these regions consist of grasses, sedges, lichens, and mosses. These are adapted to low temperatures, dry conditions, high ultraviolet radiation, and a short growing season. Mosses are found at the highest levels, growing above 21,000 feet on Mt. Everest. The flowering plant Arenaria bryophylla, a sandwort, lives above 20,000 feet.

In our next blog, we will take a look at the animal species that call these regions home, but you can check out mountain region displays at your favorite nature museum including the Jurica-Suchy Nature Museum.

Seaside

Shorelines of oceans, seas, and large bodies of water around the world are habitats for plants and animals that thrive in challenging conditions. Tides occur twice each day when water levels rise over a six hour period to cover large areas before receding to leave those same areas open to the air until the next tide starts to move inland again.

^{Nearshore habitat zones by King County, WA;} ^{Littoral Zones by US Government}

Shoreline habitat has been classified into zones often known by many different names. The intertidal zone is the area affected by changing temperature and salinity conditions as water moves in and out with each tide. The subtidal zone is the lowest and is exposed to air only during extreme spring tides or storms. The backshore zone is the highest and is exposed to water only during extreme spring tides or storms.

^{Starfish & anemone in tidal pool by Jonathan Levy}

^{Sea urchin in tidal pool, Bahia de Banderas by Jim Hoffman, Mar 2017}

Many species of animals live in each zone and are adapted to living completely submerged as well as completely uncovered by water for several hours each day. They handle the change in temperature and salinity with exposure to air or water. Tidal pools may keep some animals submerged for far longer periods. Temperature, dissolved oxygen, and salinity change far less for these organisms.

Bryozoans by John Turnbull, Sep 2021; Sea anemone by Barb Ignatius; Squat lobster, Glathea rostrata, by FWC Fish & Wildlife Research Institute, Aug 2013

Some species can be found in every zone in the ecosystem, but many are anchored to rocks or dug into the bottom. Species may prefer one zone, but get washed into another zone by wave action. Many organisms have tough outer surfaces to put up with battering waves and exposure to sun and wind. All of the occupants are subject to a wide range of predators from those that move on dry land to underwater hunters. Let’s take a look at a few of the creatures able to live in these ever-changing conditions.

The sea anemone clings to rocks and protects itself by drawing in its tentacles to become a jelly-like blob. The squat lobster can be found under stones along the shoreline. Its tail is fan-shaped and facilitates quick escapes when the animal is threatened by pulling the lobster through the water with powerful strokes. Bryozoans are small filter feeding organisms protected by a hard exoskeleton that the animal can withdraw into for protection.

^{Dog whelk, Nassarius livescens, by Budak, Dec 2016}

A mollusk called a dog whelk is a stealth predator often found on rocky surfaces. It uses its tongue to drill through the shells of other mollusks, where it squirts a digestive juice into the prey’s shell which kills and partially digests the prey. The dog whelk then uses its tongue to suck up the soupy meal. The starfish is another fierce predator. It wraps its arms around a shellfish and pulls it apart. Upon opening the shell, the starfish pushes its stomach out of itself and into the prey’s open shell where it empties its digestive juices inside, and similar to the dog whelk, creates a tasty, soupy, meal.

Sea urchins can be found clinging to hard surfaces where they feed on algae and other small, encrusted animals. Fan worms look like a leathery tube among underwater rocky crags. Several feathery tentacles fan out into the water to filter out microorganisms flowing by.

Shorelines create a habitat that is constantly changing with tides moving in and out, inconsistent weather conditions, and a large variety of flora and fauna coming and going. Learn more about this fascinating habitat at the Jurica-Suchy Nature Museum or a natural history museum near you.

^{Botanical beach at Port Renfrew by James Wheeler; Feather Boa kelp in the surf by Kqedquest, May 2007; Rocky intertidal zone in Oregon by Minustide, May 2015}

Forest Floor

Two main types of forests grow in the regions between the tropics and the poles, deciduous forest and coniferous forest. A majority of energy from sunlight is captured by the canopy vegetation, with little leftover to reach the forest floor. And yet, the lowest level of the forest has an abundance of food and organisms.

Deciduous species are mainly hardwoods including oak, birch, maple, ash, beech, and hickory. These trees have leaves that are broad and flat, designed to catch sunlight. Conifer forests are made up mostly of softwood tree species from the pine and fir families. Most conifers have leaves that are long, thin, and needle-like, a compact form of leaf that is often waxy and designed to withstand the rigors of an environment that is cold and dry for long periods.

^{Green ash tree leaf in summer & autumn by Alain de Maximy}

Chlorophyll is a chemical that is synthesized by plants and gives leaves and needles their characteristic green color. Plants use chlorophyll to absorb energy from sunlight and use that energy to power the process of photosynthesis which creates carbohydrates, providing food for the rest of the plant. Senescence, the process that occurs when a plant stops making chlorophyll, happens as seasons change and day length shortens while temperatures fall. As chlorophyll is removed, leaves and needles lose their green hues and show their underlying colors of browns, reds, and oranges even as they die and fall to the forest floor.

^{Black beetle on forest floor by Undefined, Getty Images; Forest floor fungi cluster in Autumn woods by Vladimir Srajber, Pexels; Springtail on fallen log by Henrik L, Getty Images; Lush moss covering the forest floor by Doina Gherban}

Fallen leaves create a thick layer of litter, broken down by a rich variety of decomposers including mosses, fungi, insects, and other invertebrates. Decaying vegetation releases nutrients back into the soil to be used once more as food for other forest plants. The annual leaf fall adds an estimated 2,600 pounds of vegetation per acre back into forest habitats worldwide.

In deciduous forests, all of the leaves typically fall in late autumn opening up the forest floor to sunlight in early spring. A group of plants known as spring ephemerals take advantage of this sunlight to quickly flower, bloom, and reproduce before leaves re-appear and shade once more rules the forest floor. In conifer forests, where shade is ever-present, flora is restricted to shade-loving species such as ferns and fungi. In addition, fir and pine tree needles are high in acid content and their leaf litter is only broken down by a relatively few fungi species over long periods of time.

All forest floors are rich with many organisms present throughout the year. Invertebrates including insects, fungi, and small mammals spend their entire lives living in the leaf litter. Detritus from leaf fall provides food and nutrients throughout the year to the plants and other organisms living in these wonderful habitats. As you walk the forests, no matter what the season, think about all of the life going on around you each day on the rich woodland floor.

Greene Valley Trail

As the heat abated a little bit, we decided to take a hike at the DuPage County Greene Valley Forest Preserve in Naperville, Illinois, this past weekend. On the east side, in the central part of the preserve, a 2.25 mile trail loops from the south parking lot to the Southern DuPage County Regional Trail and the Valley Trail. Trails are well-marked, wide limestone paths, with plenty of room for walkers and bicycles.

We found a pleasant, open vista that was great for birdwatchers and prairie enthusiasts alike. The Valley Trail runs alongside the east branch of the DuPage River, which makes it attractive to bird species, although there is no view of the river for hikers. While it was an overcast day making bird identification difficult, we were able to observe those seen below:

^{Birds pictured above in clockwise order: Northern cardinal, Cardinalis cardinalis, by Mshake, Getty Images; Red-winged blackbird, Agelaius phoeniceus, by Robert Jakubowski, Pexels; Song sparrow, Melospiza melodia, by BrianEKushner, Getty Images; Common yellowthroat, Geothlypis trichas, by BrianEKushner, Getty Images; Field sparrow, Spizella pusilla, by Mr Jamsey, Getty Images Signature; Gray catbird, Dumetella carolinensis, by SKHoward, Getty Images Signature}

Vegetation varies greatly, providing good protection for many of the small mammals plus lots of perches for birds. Many plant varieties could be seen and identified without leaving the trails, including those pictured below.

Black raspberry, Rubus occidentalis; Edible in season
Climbing prairie rose, Rosa setigera; Pollinator species for bees
Common milkweed, Asclepias syriaca; Pollinator species supporting more than 450 species of insects
Cup plant, Silphium perfoliatum; Leaf wraps around the stem forming a water holding cup
Eastern Black Walnut, Juglans nigra; It is allelopathic, releasing chemicals from its roots that may give the tree some advantage over its nearest competitors for food and nutrients
Elderberry, Sambucus sp.; Sambucus is Greek for an ancient wind instrument sounding as a whistle
Grey headed coneflower, Ratibida pinnata; Perennial attractive to Butterflies & birds
Hemp dogbane, Apocynum cannabinum; All parts of the plant are toxic, possibly fatal
Joe Pye weed, Eutrochium sp; Considered medicinal by early American cultures
Northern red oak, Quercus rubra; Acorns need a minimum 3-month exposure to near freezing temperatures to germinate
Sumac, Rhus sp.; Prized as a spice from the cashew & mango tree families
Virginia creeper, Parthenocissus quinquefolia; Flowering vine in the grape family
Grey poplar, Populus x canescens; Cross between white poplar and Aspen
Wild bergamot, Monarda fistulosa; Considered medicinal in use as a tea for colds

^{Scroll through pictures above using the left & right arrows}

The area supported plenty of small mammals such as rabbit, shrew, deer, coyote, and both gray and fox squirrels. We saw lots of pollinators including bees, moths, butterflies, and dragonflies. Greene Valley Forest Preserve offers a wide range of hiking trails, a scenic overlook, camping and picnicking facilities, a model airplane field, and many events, including night sky observations throughout the year. Consider catching some of the amazing sights in natural areas near you.

^{Fauna pictured above in clockwise order: Coyote, Canis latrans, by Esteban Arango, pexels; Galls on grape leaves; White-tailed deer, Odocoileus virginianus, by Stefonlinton, Getty Images Signature; White cabbage butterfly, Pieris rapae, by Bejan Adrian, Pexels; Shrew by CreativeNature_nl, Getty Images; Eastern cottontail, Sylvilagus floridanus, by Brian Forsyth, Pexels}

Pamir Wildlife

The Pamir Mountains form the western edge of the Tibetan Plateau. A pamir is a high-altitude valley or plateau surrounded by mountains. Many valleys in this range exceed 14,000 feet in altitude, and peaks reach well above 20,000 feet, making these some of the highest mountains on the Euroasian continent. The area contains the major center of glaciation in this part of the world, and all of the nearby mountain ranges are still being forced upwards by movement of the Indian-Australian tectonic plate pushing northward under the continent.

^{Pamir Knot, Hindu Kush satellite image by Jeff Schmaltz, NASA}

^{Pamir Mountains by Amanov Dmitry, Jun 2014}

Wildlife in the Pamir region is well-adapted for high altitudes, long, cold winters, and short growing seasons. Mountain people use the land for grazing large herds of domesticated sheep and yaks, but grazing space must also be shared with wild sheep, wild yaks, dozens of bird species, over 700,000 insect species, and many large predators. Let’s look at a few of the more notable species.

^{Himalayan vulture, Gyps himalayensis, on Rupin Pass trail by SahanaM, Oct 2018}

^{Himalayan vulture, Gyps himalayensis, by OK-Photography, Getty Images}

The Himalayan vulture, Gyps himalayensis, inhabits the pamirs up to 18,000 feet. These birds easily soar on warm thermal updrafts, but are not capable of long distance flight. They are often found basking in the sun on high, rocky perches. Traveling in large flocks, they follow grazing herds, keeping watch for dead animals. They can be aggressive to most other predators at a kill site, but give way to snow leopards, wolves, and cinereous vultures. The biggest threat to current populations is from drug overdoses of diclofenac, an anti-inflammatory drug that has been heavily used to treat injury in domesticated herds.

^{Herd of Marco Polo sheep in the Tien Shan mountains, by okyela, Getty Images}

^{Marco Polo sheep, taken at Berlin Zoo by Cloudtail, Aug 2018}

The Marco Polo sheep, Ovis ammon polii, is the largest sheep in the world, with large, spiral horns reaching six feet in length, with spans up to five feet across. They feed in the early morning and spend the remainder of the day basking quietly in sunny grassland. Their feet and hooves provide sure footing among sharp ridges and loose scree, and they spend nights sleeping among large boulders for protection. As the climate has warmed, there has been a loss of snowpack, resulting in less available fresh water for drinking and growing thick grasslands. These factors are driving the sheep to lower altitudes where they are more susceptible to predators including gray wolves, red fox, and brown bear.

^{Snow leopard, Panthera uncia, by Irbis1983}

^{Snow leopard, Panthera uncia, by Bernard Landgraf, Jan 2005}

Snow leopards, Panthera uncia, have seen a steady decline with a current population of fewer than 10,000. Their thick fur, gray/white with black rosettes, provides great warmth in colder altitudes, but is prized by poachers, who constitute their main threat. They are solitary animals, active for several brief periods daily, and dependent on healthy populations of ibex and sheep to eat. Powerful legs and furred paws enable them to pursue prey, in any weather, across rocky mountain terrain. After making a kill, they move the carcass to a protected area to eat. At one time, these predators were hardly ever seen, but overgrazing has caused humans to move domesticated animals into areas where snow leopards normally hunt, providing more opportunities for these predators to be killed by protective herdsmen.

^{Wild yak, Bos mutus, by Adarsh Thakuri, Jun 2008}

^{Wild yak, Bos mutus, by the Editors of Encyclopedia Britannica}

Wild yak, Bos mutus, can live in extreme conditions at altitudes up to 20,000 feet. They are large animals standing 6′ tall, weighing 1500 pounds, with black horns spanning six feet. Black, long, fine hair hangs all the way down to their feet, providing warmth for the body and legs. Yaks are very social, forming large herds of several hundred animals. They graze in two groups, with the females typically found about 300′ higher in altitude than the males. Females with young often keep to high, steep slopes where predators, including wolves and bears, are less prone to roam. Wild yaks readily hybridized with domesticated species, resulting in a natural spread of the gene pool.

^{Apollo swallowtail butterfly, Parnassius apollo, by Hectonichus, 2007}

^{Clouded Apollo swallowtail butterfly, Parnassius apollo, by Zeynel Cebeci, Adana Turkey, May 2016}

Butterflies are another common inhabitant of high-altitude mountain regions, particularly from the genus Parnassius, known as the snow Apollo swallowtail family. They are color adapted with dark bodies and wing bases that readily absorb heat from the sun providing a source of quick energy. Their normal ranges are found above 14,000 feet, and they are active for only 2-3 months annually, during the short summer season. Dozens of species have been identified with many having very small populations, numbering only a few hundred individuals. Poaching for collectors remains their main threat.

At the Jurica-Suchy Nature Museum, we have many of these and other species on display in our mountain region diorama. Consider a visit to learn more about the wildlife of high-mountain plateaus worldwide.

^{High-altitude species from around the world on display at the Jurica-Suchy Nature Museum include: Marco Polo argali sheep, Alaskan brown bear, bighorn sheep varieties, mountain goat.}

Autumn Foods

Meteorological fall began September 1st, marking the beginning of cooling temperatures that lead into winter, the coldest time of the year in the northern hemisphere. As the days begin to cool, many plant species are producing ripe fruits and seeds and starting the process of going dormant until next spring’s warming temperatures and longer days signal a beginning of the next growing cycle. Some animals, especially birds, travel long distances, migrating to areas that stay warm throughout the year. Those who stay through the coldest months depend on having food sources available even while plants are dormant.

_{Grey-headed coneflower seed head by Laura Fischer Photography}

The best winter food sources for wildlife are native plants with berries and seeds available throughout the colder months. Birds including woodpeckers, robins, waxwings, bluebirds, thrushes, chickadees, quail, and thrashers rely on robust insect populations in summer. In winter, when insects are no longer available, having another food source such as seed heads and berries left standing in your garden fulfills this need while adding visual interest and wildlife watching opportunities for you.

^{Food items shown above: Acorns on forest floor by Liz West, Oct 2006; Shellbark hickory nuts by HeikeRau, Getty Images; Pine cones with seeds by GordonImages, Getty Images}

Several tree families including pine, hickory, oak, and cherry offer fruit and nuts lasting through the winter. Along with grass and wildflower stems, trunks and branches also provide habitat for insect eggs and larva that will emerge in the spring. Over winter, insects in these stages are available as food for foraging species that use beaks and claws to dig them out. Stems growing close together provide additional benefits as thickets that provide protection against cold winds and harsh weather and hiding places that are safe from other predators.

^{Berries & Seeds above: Aster seeds by David Hansche, Getty Images; Sunflower at sunset by Hazal Ak, Getty Images; Wild elderberries by StargateChris, Getty Images; Thistle seeds by JTCanada, Getty Images}

Sunflowers, elderberries, and serviceberries are important food sources for fall migrators and winter inhabitants, providing fat and energy to stay warm and active. Aster, thistle, and conifer seeds released throughout the colder months are a favorite food source for finches and other small perching birds. Oak acorns, beechnuts, and hickory nuts are eaten by many woodland animals including squirrel, chipmunk, deer, wild turkey, fox, and quail.

^{Wildlife enjoying an offering: Blue tit on suet by Hedera.Baltica, Dec 2022; Lunch by Audrey, Feb 2008; Pine siskins on thistle by Yooperann, May 2015; Purple finches by Stan Lupo, Oct 2016}

Some of these animals also forage through our backyards in winter as many berry producing plants in the wild are stripped bare during late autumn and early winter. Backyard plantings and feeders provide important supplementary food sources for these animals. A variety of species to consider planting include American persimmon, blackberry, blueberry, elderberry, raspberry, cranberry, paw-paw , and prickly pear cactus, holly, sumac, hackberry, viburnum, hawthorn, bayberry, red cedar, and juniper. You can learn more under Garden For Wildlife on the National Wildlife Federation website at https://www.nwf.org/Garden-for-Wildlife/Food.

Nature journaling is a great way to track your observations and learn more through later research

Opportunities to observe wildlife in your own backyard can be an exciting way to learn. Try tracking which plants are being eaten and at what times during the changing seasons. Record the weather conditions during those periods to learn what foods are relied upon during colder, harsher winter weather. Try a variety of suet, seed and nut varieties in feeders to attract a range of animals to your backyard for fun wildlife watching and education.

Oak Tree Habitat, pt.3

In the past couple of blogs, we learned that oak trees are a keystone species in their habitat, especially for the vast network of relationships between oaks and insects.

^{Ladybug on oak tree leaf by EMFA16, Getty Images}

^{Leaf litter and under-bark room for rent, by Wayne S. Grazio, Nov 2013}

^{Insect holes & homes on cork oak, Quercus suber, by Bloor4ik, Getty Images}

Oak trees and their surroundings provide shelter and food from leaves, wood, bark, sap, flowers, pollen, and acorns to thousands of species of insects and other invertebrates. Shelter is provided on the tree, inside cavities or other fissures, among the leaf litter, and around the root systems. As oaks age, there are more opportunities for shelter and food, including after branches or the whole tree dies and falls to decay on the forest floor.

^{Chickadee nest by Jack VandenHeuval, Getty Images}

^{Chickadee eating a caterpillar by Bettina Arrigoni, May 2018}

Over 900 caterpillar species have been identified in oak habitats, more than three times the number found in forests dominated by maple trees. Canopy leaves and branches provide shelter and nesting opportunities for dozens of bird species who find a ready source of food within the insect populations. Ninety percent of bird species feed insects, especially caterpillars, to their young. The Carolina Chickadee feeds four to six chicks for 16 days before they fledge. Mealtimes require 400 to 500 caterpillars each day.

^{Aphids and ants by oday222, Getty Images Pro}

^{Philodromus praedatus spiders live mainly in mature oak trees, by Nikk, May 2016}

^{Oak gall by Michael Boubin, Getty Images}

Several species of flies and wasps lay their eggs on oak trees, stimulating a growth hormone in the tree to grow a gall, an outgrowth of bark, around the eggs. When the larvae hatch, secretions from the gall feed the larvae, and the gall provides protection to the developing insects. The abundance of insects attracts other invertebrates from higher up on the food chain. Spiders frequently inhabit mature oak trees hunting and feeding on many of the insect species. Aphid colonies are often found on oak trees, but cause little damage to the tree. Aphids feed on the sap from the tree and secrete a sticky, sugary substance called honeydew, a favorite food for ants. The ants protect the aphid colonies, keeping them underground during inclement weather and herding them up the tree in summer to ensure the aphids are well fed to keep producing more honeydew.

^{Fall webworm, Hyphantria cunea, by Anita Gould, Sep 2015; Polyphemus moth caterpillar, Antheraea polyphemus, by Ed Uthman, Sec 2018; Speckled wood caterpillar, Pararge aegeria, by Dean Morley, May 2013; Linden looper caterpillar, Erannis tillaria, by sankax, Jun 2009}

Insects and oak trees have created an environment rich in food for many of its inhabitants. According to Doug Tallamy, a leading entomologist at the University of Delaware, “caterpillars transfer more energy from plants to other animals than any other type of creature.” The loss of habitat for insects puts considerable strain on all other environments, including ones supporting ourselves. Insects do most of the work of pollination, allowing plants to reproduce. They also provide for quick decomposition and the return of nutrients to the soil for growing new plants. Insects are a driving force of the world’s food webs and are necessary for a healthy environment.

There are over 400 species of oaks worldwide, with about one quarter found in North America. As we have briefly touched upon in this series of blogs, oak trees provide opportunities for healthy habitats for many other species. For information and further discussion on the relationships between caterpillars and oak trees, please see The Nature Of Oaks, by Doug Tallamy.

Oak Tree Habitat, pt.2

In the last blog, we discussed oak trees as a keystone species, substantially affecting the types and abundance of other species in their habitat. There are 400-500 species of oaks worldwide, supporting an extraordinary 2,300 wildlife species not including fungi, bacteria, and other microorganisms. Oak trees in all stages of life and death have numerous biotic relationships with wildlife.

^{Badger in tree cavity by Byrdyak, Getty Images||Golden millipede in Lagos by efeghali, Getty Images||Neanura springtail by Henrik_L, Getty Images||Pileated woodpecker in oak tree by mtruchon, Getty Images||Slug & rollie pollies by Sonya Kate Wilson, Getty Images||Wood Mouse in tree cavity by byjohn, Getty Images}

Fungi are often identified as attacking oak trees, but they can have very beneficial relationships. Fungi growing in the ground assist an oak tree in getting nitrogen, phosphorous, and other nutrients out of the soil, and in return get carbon and energy from the sugars in the tree’s sap. Oaks provide a place to live for over 700 species of lichens, plus uncounted liverworts and mosses. Lichens covering the oak’s surface help to keep them free of fungal infections and invasive insects. Liverworts and mosses help oaks to retain water and release it into the soil over a long period of time. As oak limbs fall and decay, water retention softens the wood providing food and habitat for decomposers.

Green moss on oak tree by tntemerson, Getty Images

Lichen & peat moss on oak by Sean Gardner, Getty Images

Fallen oak leaves are slow to decompose due to their tannin and lignin content, both preservative compounds. Leaf litter, composed of several layers of fallen leaves, becomes habitat for many millions of species including millipedes, springtails, woodlice, slugs, beetles, ants, and other organisms that feed on decaying plants. Through their activities, the creatures of the leaf litter help to return nutrients to the trees.

Oak forest leaf litter by Tina_C_Olsen, Getty Images

Acorns, with high amounts of fats, proteins, and carbohydrates, are one of the healthiest and most sought after foods in the woodland. White oaks, living between 200 and 300 years, will produce about 3 million acorns during their lifetime. Many bird species eat acorns, but oak trees enjoy a special relationship with blue jays, whose beaks are strong enough to pry an acorn open. In autumn, blue jays enjoy feeding on acorns, but also cache them for winter, burying several at a time under a few inches of soil in various locations up to a mile from the originating tree. Although blue jays cache large quantities of acorns, they can only remember and retrieve about 25% of them, allowing many new oak trees to grow and spread into new areas.

Blue jay with red oak acorn by mirceaux, Getty Images

Oak trees support 31 mammal species who consume acorns for food, use the tree for shelter, or use the surrounding habitat for hunting. Gray squirrels and red squirrels favor acorns in the autumn and throughout the winter from caches hidden in nearby locations. They remember far more cache locations than blue jays, but there are still uneaten acorns that will germinate in spring to start new trees. Acorns are also a favorite food for badger, deer, wild board, and wood mouse.

^{Gray squirrel eating acorn by viktor2013, Getty Images}

^{Red squirrel with acorn by Neil_Burton, Getty Images}

Oak trees offer shelter for many species. Squirrels often build their nests high up among the leaves that provide protection from weather and predators. Dead branches, especially those with cavities, may remain on the tree for many years, providing excellent roost sites for bats. Open limbs, leafed areas, and cavities all provide nest sites for a variety of birds. In addition, the many insects drawn to oak trees provide a ready source of food for all of these nesters. Humans have been acorn consumers for millennia. Raw acorns, high in tannin content, can be toxic in larger quantities; but, properly prepared, acorns are high in calories, vitamin C, starch, magnesium, calcium, phosphorous, and antioxidants. They have been a food staple in many cultures and can be found in the records of ancient Greeks, Iberians, Japanese, and English.

Oak trees have many direct and indirect relationships with insects, which we will explore in the next blog.

Midwestern Prairie

Grasslands make up the largest habitat in North America and cover about one-quarter of the Earth’s surface. There are many different types of grasslands, each with its own descriptive name. Prairie, found in North America, is from the French word for “meadow;” steppes, found in Asia, is Russian for “flat, grassy plain;” pampas, found in South America, is from Quechua meaning “flat surface;” and veldt, found in Africa, is from Afrikaans meaning “field.” In all of these areas, grasslands are characterized by flat or gently rolling countryside.

From upper left: The African veldt by Cello8, May 2007; Sunrise on the Mongolian steppes by Nicolas Mirguet, Apr 2011; Pampas grasslands, Uruguay, South America by Guilherme Boettcher, May 2010; Nachusa Grasslands, Lee County, Illinois by Justin Meissen, Jul 2007

Prairies in Illinois were formed by the action of glaciers retreating northward at the end of the last ice age. Massive ice fields compacted the soils and flattened the landscape. Many areas retained much of the melting ice in ponds, creeks, and rivers. These provided much needed moisture to help establish the new flush of vegetation that moved in as the climate warmed.

White River Prairie, Wisconsin by Joshua Mayer, Aug 2016

Several different types of prairies can be found, differentiated by the mixture of grasses and flowering plants, called forbs. We classify prairies as wet, mesic, meaning moderately moist, or dry. The determination is made based on how much water is retained in soil layers, but can be greatly influenced by temperature, rainfall amounts, and fire. Grasses have narrow leaves, can grow in drier environments, and are the dominant plant type in most prairies. Forbs have broad leaves and require more moisture than grasses. Prairie plants often have deep root systems to access water and nutrients.

From upper left: Big Bluestem, Andropogon gerardii by Matt Lavin, Sep 2019; Rattlesnake master, Eryngium yuccifolium by Adam B, Jan 2017; Grey coneflower seed heads, Ratabida pinnata by JanetandPhil, Nov 2010; Frosty Prairie dock, Silphium terebinthinaceum by Anne McCormack, Dec 2010; Indian grass, Sorghastrum nutans by Douglas Mills, Sep 2015

Animals that inhabit midwestern prairies are adapted to this habitat. They are able to find water and food in drier conditions, when water is scarce. They avoid the hazards of fire sweeping across the landscape. They keep warm during cold winter months. They avoid predators in a landscape with few hiding spaces. Many species are able to burrow underground for warmth, to avoid fire, and to escape predators. Others live near the ground in thicker vegetation that provides cover from wind, cold, and attack.

From upper left: American toad, Bufo americanus by Alan Huett, Jul 2008; Sedge wren, Cistothorus platensis by Joshua Mayer, Jul 2015; Thirteen-lined ground squirrel, Spermophilus tridecemlineatus by ChristaR., Nov 2016; Prairie kingsnake, Lampropeltis calligaster by Peter Paplanus, May 2022; Northern harrier, Circus hudsonius by Wendy Miller, Dec 2010

At this time of year, prairie plants are starting to go dormant and many bird species are migrating southward to warmer climates where food and water is abundant. It is a great time to get out and observe plants as they set seed and surprise us with the many hues of autumn. Birds are abundant as flocks fly overhead on their migration. Birds that spend the winter here are searching for areas that will provide seed and cover during the coming cooler months. Other animals are out to gather plants for insulation in their winter dens or seeds to store in their larder. Keep your eyes and ears open as you walk the prairie paths this month.

Midewin tallgrass prairie preserve, Wilmington, IL by CheapShot, Jun 2012

Carnivorous Plants

Plants and insects have myriad relationships to one another. Some are mutually beneficial, as when plants offer nectar to feed insects which in turn pollinate the plants. Other relationships only benefit the insects when they feed on leaves, stems, and roots. For carnivorous plants, preying on insects to fulfill their need for nitrogen and other nutrients benefits only the plants.

^{Venus flytrap, Dionaea muscipula by Len Worthington, Aug, 2016}

Pitcher plants are carnivorous, living in bogs and fens found in warm weather areas. In North America, most species are found along the southeastern coastal states from Texas to West Virginia. Bogs are depressions filled with rain or melted snow, while fens are similar but get their water from surface or groundwater. Both types of wetlands are low in oxygen and nitrogen, very acidic, and often quite cold. These characteristics slow down the rate of decay in the vegetation of the wetland, further reducing the availability of nitrogen which is a vital component of chlorophyll, the compound used by plants, along with water, carbon dioxide, and energy, to photosynthesize sugar for food.

^{Tracy’s sundew, Drocera tracyi by Matthew Paulson, May 2022; Venus flytrap, Dionaea muscipula by Judy Gallagher, Jun 2022; White-topped pitcher plant, Sarracenia leucophylla, showing downward hairs by Aaron Carlson, Sep 2013}

Carnivorous plants use several strategies to attract and trap insects. Pitfall traps have slippery faced leaves forming a funnel with a pool of digestive enzymes waiting at the bottom. Downward facing hairs on the leaves make it harder for insects to climb out. Some plants use an opposite strategy and cover their leaf surfaces with a sticky secretion, trapping any insects that land on them. Still others have a leaf-like structure made of two halves that snap together when an insect lands on an inner surface, trapping the insect inside. In both of the last two instances, digestive enzymes are then released to cover, kill, and break down the insect body for absorption by the plant.

^{White-topped pitcher plant, Sarracenia leucophylla, traps separated from flowers by NC Orchid, Apr 2016}

^{Two-spotted bumblebee, Bombus bimaculatus by Judy Gallagher, Jun 2022}

Carnivorous plants are insect pollinated and must be able to attract pollinators without trapping them. All of the plant species go through a dormant period as seasonal temperatures get cooler. Traps die back and are regrown when warmer weather returns. In several species, flowers bloom and attract pollinators with nectar, completing fertilization before traps develop. Other plants separate the flowers and traps by a physical distance. Traps usually lie close to ground level to attract crawling insects, and flowers are grown on top of tall stalks to attract flying insects. A third method is to make the flowers less attractive to potential prey, and make the traps less attractive to potential pollinators. This is achieved by using different colors, patterns, and scents on flowers and traps.

^{Metallic green sweat bee, Agapostemon sericeus by Dann Thombs, Aug 2008}

^{Cobra lily, Darlingtonia californica by Charles Peterson, Mar 2018}

Whether you are growing these unique plants at home or viewing them in a botanical garden or out in the wild, some of the plants and their pollinators to watch for include the white-topped pitcher plant, Sarracenia leucophylla and the two-spotted bumblebee, Bombus bimaculatus; the cobra lily, Darlingtonia californica and the mining bee, Andrena nigrihirta, Tracy’s sundew, Drosera tracyi and the metallic green sweat bee, Agapostemon sericeus, and the Venus flytrap, Dionaea muscipula and any of the hoverfly species, Toxomerus sp.

^{Bog landscape by Chris Moody, Jun 2009}

Oak-Hickory Forest

Oak-hickory forests makeup one-fourth of all the woodlands in the eastern United States. At the end of the last ice age, oaks were only found in the Appalachian Mountains and the driftless section where glaciers did not form in southwestern Wisconsin. In the last 15,000 years they have repopulated the land from the Mississippi River to the Atlantic coastline.

Clockwise from top left: Quercus alba, white oak by Chris Andrei, Getty Images; Quercus palustris, northern pin oak by Michel VIARD, Getty Images; Quercus rubra, northern red oak by ValerijaP, Getty Images; Fraxinus pennsylvanica, green ash by Garsya, Getty Images; Carya ovata, shagbark hickory by Elmar Langle, Getty Images; Prunus serotina, black cherry tree by Ina Hensel, Getty Images

Oak-hickory forests are an open woodland community where trees make up less than 10% of the plant life. Species of both the red oak and the white oak groups dominate these wood including Northern red oak, Quercus rubra, black oak, Quercus velutina, white oak, Quercus alba, and bur oak, Quercus macrocarpa. Two members of the hickory family, shagbark hickory, Carya ovata, and bitternut hickory, Carya cordiformis, are also found in abundance. These forests are rich with several other tree species most notably red maple, Acer rubrum, sugar maple, Acer saccharum, black cherry, Prunus serotina, black walnut, Juglans nigra, and green ash, Fraxinus pennsylvanica.

^{Arisaema triphyllum berries by ES3N, Getty Images}

^{Arisaema triphyllum, jack-in-the-pulpit by Holcy, Getty Images}

The open structure of the forest supports a large variety of other plants that offer food, shelter from predators and weather, and places to raise a family. Food sources are plentiful including fruit-bearing plants of the genus Vaccinium, which includes blueberries and raspberries, and vines from the genus Vitis, which includes several species of wild grape. Bloodroot, Sanguinaria canadensis, and Jack-in-the-pulpit, Arisaema triphyllum, along with several clovers, attract birds and insects that attract larger predators, creating a rich forest community. It is estimated that oak-hickory forests support over 300 animal species including birds, mammals, insects, reptiles and amphibians.

^{Oak woodland by fotoVoyager, Getty Images Signature}

Oak trees provide a haven for wildlife. Acorns, the fruit of an oak tree, are large and heavy, so they do not spread far from the tree. They offer good nutrition and are a favorite of many wildlife species, whether eaten immediately or cached and eaten over time. Oak trees retain their dead leaves throughout the winter, not letting them fall until early spring. The leaves provide shelter from wind and rain, as well as hiding many smaller birds and mammals from airborne predators. Oak trees have craggy bark providing shelter for insects and other small animals including many amphibian species that overwinter under the bark.

After dying, oak leaves retain tannin, a chemical that slows down their decay. As leaves build up on the forest floor year after year, they create thick layers used by amphibians, reptiles, small mammals, and insects for shelter from predators and weather. In winter, the leaf layer provides insulation from the snow and cold, allowing small animals to move around under the snow, hunting for food, or moving to other sites. However, the leaves can be advantageous to some predators, as well. Owls, and other nighttime hunters, have excellent hearing and can easily detect the sounds from crackling leaves as prey attempts to hide and flee.

^{Gnarled tree with large cavity from wepix, Getty Images Signature}

^{Nature lives forever in fallen trunks by Oleksiy Brunets, Getty Images}

Many tree species are susceptible to dry rot of their interior wood, and none more-so than members of the red oak family. This provides natural cavities for woodland species. Woodpeckers, owls, chickadees, and nuthatches, plus squirrels, raccoons, bats, amphibians, and reptiles all use cavities for shelter and protection. Almost 40% of animal species inhabiting oak-hickory forests will use cavities at some point in their lifetimes. As trunks and branches decay and fall to the forest floor, they create opportunities for food and shelter. In addition, animals drawn to these spaces provide food for larger predators.

As you walk through forested areas over the summer, take note of the tree species and the overall structure you observe Can you spot holes in trees, logs laying on the forest floor, and thicker layers of leaf cover? Are the woods open where you can see possible lanes of movement? What plants have fruit or seeds? Keeping a journal of observations helps us to identify the changes and enjoy these rich habitats.

^{Dry oak forest in springtime by Meinzahn, Getty Images}

^{Swamp oak forest in springtime by Aleksander, Getty Images}

Boreal Forest in Winter

The boreal forest is the largest tract of woodland on earth covering 11% of all land area, half again as large as the Amazon rainforest. It stores 30% of the sequestered carbon on earth. The area also contains a mosaic of wet meadows, ponds, lakes, marshes, and bogs interlaced among the trees. Tree species include many conifers, dominated by spruce, plus aspen, birch, willow and alder. The animal life is abundant, with every species that was there before European settlement still remaining.

^{Boreal Forest panorama by Mliberra, getty Images}

The boreal forest is distinguished by short, hot, wet summers and long, dry, cold winters. When the last glaciers retreated northward, many holes and fissures were left behind. As the ice melted, all of these depressions were filled with water. The underlying geology is mostly granite shield, a rock layer that holds the water in and contains few minerals that dissolve in water, yielding very clear water that does not promote algae or bacteria growth. Most lake life is found in the shallow, warmer edges which also provide support to nearly all of the land-based fauna.

^{From upper left clockwise: Alder tree by Mantonature, Getty Images Signature; Spruce trees by Hannu Koskela, Getty Images; Willow tree by smarko , Pixabay; Aspen trees by Adamisovitsch, Getty Images}

Winter time presents many challenges including less sunlight, colder temperatures, less available water, less food and shelter, and increased severe storms. Animals that are active daily have higher energy requirements in winter. They must often change their dietary sources to whatever is available in winter. Grey squirrels and beavers cache food during warmer periods. Birds eat foods higher in calories such as nuts, seeds, dried fruit, and insects found under tree bark. When changes are consistent from year to year, species develop adaptations to meet the requirements of each season and are able to live comfortably throughout the year.

Shelter becomes not only a place to hide from predators, but also provides protection from weather extremes. Snow of different thicknesses and weight covers the landscape. Snow is also a great insulator, keeping cold winds away from exposed skin. There is normally a layer of air between the ground and the snow cover immediately above. Temperatures in this space are warmer than the exposed air above the snow creating a winter habitat that is vitally important for many species. Mice and voles create burrows under the snow where they can huddle together for added warmth. Similarly, air pockets surrounded by a heavy growth of conifer needles create spaces above the snow cover for birds and some larger mammals to shelter. And many larger species will nestle into the snow pack to shelter from storms and wind.

^{Spruce grouse by Impr2003, Getty Images}

^{Willow ptarmigan by Alex Berger, Mar 2022}

Spruce grouse, Canachites canadensis, and willow ptarmigan, Lagopus lagopus, are not able to fly more than several yards. They grow feathers on their feet to insulate them and aid in traction. Grouse use the air layer at ground level to shelter in.

^{Portrait of a snowshoe hare by Jim Cumming, Getty Images}

^{Canada lynx by Carol Gray, Getty Images}

Ptarmigan, along with snowshoe hares, Lepus americanus, and short-tailed weasels, Mustela erminea, all change color to pure white to hide from predators. Snowshoe hare and Canada lynx, Lynx canadensis, have very large feet that aid in walking on snow without sinking in. Arctic fox, Vulpes lagopus, are winter specialists with compact bodies and short legs and ears that limit their exposure to cold, and large, furry paws that enable them to walk on top of the snowpack. With their long, bushy tails wrapped around their heads, they can withstand winds and temperatures to fifty below zero.

^{Stayin’ warm, Arctic fox by PEDRE, Getty Images Signature}

You can learn more about this cold but wondrous habitat by searching online for boreal forest, referring to the southern portions of the habitat, or taiga, referring to the northern portions. Also, look for information concerning seasonal adaptations for species in your own area, or visit a local natural history museum such as the Jurica-Suchy Nature Museum in Lisle, Illinois.

Desert Habitat, pt.3

In the past two blogs, we have explored deserts and the plants which inhabit them. Animals native to these habitats have general adaptations for coping with temperature extremes, aridity, and finding water, food, and shelter. Strategies include hunting during cooler hours including at dawn, dusk, or overnight; obtaining water from sources other than standing water; burrowing underground to avoid temperature spikes and solar radiation; ability to conserve water in their body; ability to dissipate body heat; and being well-camouflaged. Look for each of these adaptations in the following species that live in our desert regions.

Greater roadrunner, Geococcyx californianus, by Tony Cyphert, Sep 2018

Ord’s Kangaroo Rat, Dipodomys ordii, by Andy Teucher, Jun 2005

The greater roadrunner, Geococcyx californianus, can only fly for several seconds at a time, but can reach speeds up to 17mph when running. They hunt early in the morning, retiring to shade when temperatures heat up mid-morning. Water requirements are met from foods including grass and prickly pear cactus, plus prey that includes lizards, scorpions, and rattlesnakes. Roadrunners do not urinate, but can excrete salt and save the water. They have an un-feathered area under their chins used to dissipate body heat. Ord’s kangaroo rat, Dipodomys ordii, is another species that gets all of their water requirements from the seed they eat. Individuals live in underground burrows, coming out only at night to feed. They conserve water in their bodies and do not sweat or pant. They have many predators, but with a 9-foot jump and excellent hearing, they are hard to catch. Seeds are collected and stored in their burrows, and they will gain 50% more water from the underground humidity before being eaten.

Horned Toad, Phrynosomasp., by TJFrom AZ, May 2009

Gila monster, Heloderma suspectum , by Karla Kishinami, Apr 2012

Horned toads, Phrynosoma spp., are small, ant-eating lizards with thick scales to conserve water and deter predators. To escape a predator, these animals can squirt a directed stream of blood from their eyes up to five feet away. They are sandy-colored with undefined outlines allowing them to easily hide amid rocky outcrops. Normally active during the day, they can retreat to burrows or under rocks if temperatures become too hot. During winter, horned toads will spend a period of inactivity, called brumation, in underground burrows. The Gila monster, Heloderma suspectum, is another lizard with armor protected skin marked with black and pink coloration that camouflages them well in sandy soils. They shelter from daytime heat under rocks and shrubs, emerging in early morning or evening to hunt small mammals, lizards, insects, and bird eggs. One of only two venomous reptiles in North America, their venom adversely affects their prey’s nervous system. The short, thick tail stores water in fatty tissue for use when needed.

Tarantula, Aphonopelma sp., by Saguaro National Park, Nov 2020

Western coral snake, Micruroides euryxanthus, by Ashley Wahlberg, Apr 2016

The tarantula, Aphonopelma spp., shelters in deep burrows lined with silk to prevent the sand from caving in. They are nocturnal hunters of insects, arthropods, and small lizards with a bite that delivers a small amount of venom to stun their prey. Venom immediately starts to break down tissue to liquify the meat, allowing the spider to use sucking mouth parts to draw in its meal. The Western coral snake, Micruroides euryxanthus, is brightly colored with red-white-black-white banding and venom that is twice as deadly as most rattlesnakes. They are very secretive, living under rocks or buried in the sand. Coming out at night or on some overcast days, they hunt for lizards and other snakes. Venom causes rapid paralysis and respiratory failure, although due to their small size and small amount of venom injected, they are not a threat to humans.

Like many environments, a healthy desert community exists when plants, animals, and habitat are all present and undisturbed. With much of the life in deserts underground, walking off trails and driving off roads can negatively impact what is under the surface. Removing plants and rocks used for water and shelter is equally damaging. I encourage you to get out, observe, and enjoy this unique habitat, or research many of the fun and interesting adaptations at a local natural history museum.

^{Pictures above clockwise: Bark scorpion by Josh More, May 2014; Cactus wren by Mick Thompson, Feb 2019; Jackrabbit, by Mark Gunn, Mar 2014; Javelina, Sonora Desert, by Richard Bonser, Jan 2005; Tarantula hawk wasp by Jim Mulhaupt, May 2010; Sonoran mud turtle by Grigory Heaton, Sep 2022; Round tailed ground squirrel by Wendy Miller, May 2022; Hoary bat by Michael Pennay, Sep 2009; Cactus deermouse by J.N.Stuart, Oct 2011}

Desert Habitats, pt.2

Pequop Mountain foothills, Great Basin Desert, Nevada by Matthew Roth, Apr 2016

Big sagebrush, Artimesia tridentata by RCWinton, Aug 2008

There are four major deserts in North America. The Great Basin runs from central Idaho to northern Arizona. It is a high altitude plateau, with very cold winters, mild summers, and few plant species characterized by big sagebrush, Artimesia tridentata.

The Mohave Desert, a small area covering southern Nevada and southeastern California, is known for its cold, rainy winter season resulting in hard freezes leaving little water available. The Joshua tree, Yucca brevifolia, a yucca variety growing above 3000′, is the tallest plant in the area.

Joshua tree, Yucca brevifolia, by Melissa Delzio, May 2011

The Chihuahuan Desert, covering the high altitudes of northern Mexico ,is subject to hard freezes from arctic winds scouring its surface. Winter rains occasionally occur supporting a rich diversity of low shrubs and small cacti.

The Sonoran Desert, covering southern Arizona and the Baja Peninsula, has high and low altitudes, hot to mild temperatures, and periodic rainfalls. The winter season, with mild temperatures, does not limit the plant and animal diversity as much as in the other three, colder deserts. The Sonoran Desert, which includes several habitat types, supports a rich variety of species including 2000+ plants, 350+ birds, 100 reptiles, and 30 native fishes.

Desert plants exhibit many similar features that make them well-adapted to the hot, dry conditions of their native habitat. Most are succulents, plants with thick, fleshy stems to retain water for use during hot, dry periods. Plants often have spines in place of leaves to reduce the surface area exposed to wind and heat, greatly reducing water loss from evaporation. Spines also add a layer of protection to prevent animals from eating the plant. Stems are green, containing chlorophyll and water, and this is where photosynthesis takes place. Bloom periods and pollination occur during winter or nighttime when cooler temperatures prevail.

Creosote bush, Larrea tridentata, in flower by Malcom Manners, Apr 2017

Century plant, Agave americana, by J.Maughn, Mar 2020

Several distinctive native species characterize North American deserts including cacti, succulents, and other plant varieties with spines. The creosote bush, named for its distinctive antiseptic smell, grows three to nine feet tall and has small yellow flowers. This plant grows in colonies of cloned bushes which may live for long periods as epitomized by the King Clone of the Mohave Desert, estimated to be about 12,000 years old. The century plant, another long-lived plant, is a species of agave noted for its large cluster of wide leaves with spiny edges. The plant may live up to 30 years, but flowers only once, then dies.

^{Clockwise from top: Prickly pear by Fishfoot, Mar 2018; Prickly pear buds by Diandra Rodriguez, Nov 2011; Prickly pear cacturs in bloom by Stepan Mazurov, May 2009; Prickly pear cactus glochids by Tracie Hall, Nov 2017}

Often seen cacti include the prickly pear cactus which is actually a group of several species all native to North America. Modified stems, called pads, are often mistaken as leaves. These store water, photosynthesize food and sugars, and produce flowers. All species grow long, single spines in addition to glochids, clusters of very fine, tiny spines. Glochids are often not noticeable but can be easily detached if brushed against and once lodged in the skin are painful and difficult to remove. The saguaro cactus is another common plant. Its distinctive shape, with a tall central column and “arms” growing at right angles, is easily recognizable as one of the Sonoran Desert’s native species. It is the largest cactus in North America, growing to over 40′ high, and living 100 years or more. White, waxy flowers open only at night to attract bats, its preferred pollinator.

Saguaro cactus by Ralph Earlandson, Apr 2017

Many natural history museums have excellent displays of plants and animals from world-wide desert biomes, including one of my favorites, the North American desert display at the Jurica-Suchy Nature Museum. In my blog next week, I will introduce some of the notable animals and their adaptations to desert life.

Desert Habitat, pt.1

A biome is a type of global habitat characterized by temperature, rainfall, latitude, elevation, and wind pattern. Plants, which are unable to move about, are used to characterize each type of biome, and are well-adapted to their native habitat. The desert biome is the driest habitat found on earth. In a desert, plants are widely spaced and are adapted to life with little or no moisture except for annual periods when brief rains may be heavy, sparse, or not occur at all. Even within these harsh conditions, plants may be present supporting a rich diversity of species.

_{Clockwise above: Hidden Valley, Joshua Tree solitude by Don Graham, Apr 2013; Sonoran Desert sunset by Jasper Nance, May 2009; Sonoran Desert layers by Art DiTommaso, Apr 2020; Mohave Desert by Melissa Delzio, May 2011}

A common factor of all deserts is the aridity or lack of moisture. Aridity can be determined by how much water is available in the habitat combined with the rates of evaporation from heat, radiation, and wind exposure. Another consideration in determining aridity is how much moisture the air can hold. Neither extremely hot nor extremely cold air easily retains moisture. Freely running water is only available in the desert for the briefest period of time immediately following a rainfall, a scarce and unpredictable event.

Deserts form in areas where dry air predominates. Understanding how weather influences the Earth’s surface helps to identify where to find the world’s desert regions. At the equator, air is warmed by direct sunlight causing it to rise and absorb large amounts of water from the oceans. When the warm air mass encounters cooler air at higher altitudes, it spreads out both northward and southward. Cooler air causes the absorbed moisture to condense into rain in tropical latitudes. The outward moving air mass, now dryer and cooler, also begins to fall back to the earth’s surface, picking up heat from the sun’s radiation and the hot ground. Air masses generally descend and move back towards the equator around 30˚ latitude, which is where many deserts occur.

Rain shadow on leeward side of mountains on Oahu by Loren Javier, Jun 2010

Exploring Greenland’s grass and Dry shrub vegetation by Eugene Kaspersky, Jul 2016

Deserts can also be formed from rain shadows and temperature extremes. As prevailing winds encounter mountains, air is forced up the windward side and flows down the leeward side. As air rises, it cools, once again condensing any moisture into rain which falls on the windward side. Dry air coming over the mountain forms a rain shadow that leaves little moisture for the habitats on the leeward slopes. Temperature extremes occur in both hot and cold regions. Dry, hot air descending from the tropics form warm deserts. Cold, dry air from polar winds form cold deserts such as those found in Antarctica and Greenland.

Desert temperatures vary widely, both daily and seasonally. Dry air and cloudless skies allow a maximum amount of solar energy to reach the surface where it is absorbed and converted to heat, raising daytime temperatures dramatically. At night, air temperatures plummet as solar radiation ceases and heat is quickly wicked away into the cooler atmosphere. Temperatures may fluctuate as much as 100˚ in a 24-hour period. Ultraviolet radiation also presents other challenges to living organisms. Intense sunlight can damage skin cells, degrade retinal tissue, and destroy chlorophyll molecules in plants.

Rain in the Sonora Desert summer monsoon season by Kevin, Aug 2013

Green Sonoran Desert after brief winter rain by Wayne S. Grazio, Fwb 2017

Deserts experience seasons, just as those found in other biomes. In desert areas of Arizona, there are five recognized annual seasons. Spring, February through April, is characterized by mild temperatures and windy days. It is a dry season as warm winds wick away all exposed moisture. Summer, in May and June, is hot and dry, with many species remaining dormant to escape the heat. Summer monsoons, July through mid-September, signals a change in wind direction bringing moister air northward from the tropics. Frequent thunderstorms occur most years providing a period of replenishment for shrubs and trees. Autumn, in October and November, returns to warm and dry conditions. Winter comes in December and January bringing in mild temperatures and the possibility of a few rain showers.

The climate of the world’s deserts makes survival difficult, but many species have adapted to these conditions in some remarkable ways. Next week, we will investigate the desert regions of North America and their vast diversity of life.

_{Clockwise above: Blooming hedgehogs by Jasper Nance, Apr 2010; Desert globemallow by Take-A-Hike Arizona, Mar 2009; Desert woollystar, Eriastrum eremicum, Sonoran Desert by SSBiker1, May 2011}

Forest Litter, Hand Lens Views

This week we take a look at one other group of species found in the forest litter, those that we can best observe using a hand lens. Springtails are tiny insects colored gray, brown, and white. They are wingless with a worm-like body, and are named for a unique abdominal structure that allows them to suddenly jump. They are extremely numerous, ranging from 500 to 50,000 individuals per square meter. Springtails may form dense groups that come out in winter on top of new fallen snow earning them the nickname “snow fleas.” They are an important species of decomposer feeding on fungi, decaying vegetation, and live vegetation.

Springtail, genus *Isotoma*, by Ryszard, Aug 2009

Springtails, aka Snow Fleas, by mwms1916, Mar 2015

Soil mites are members of the arachnid family, the same as spiders. When viewed up close, they may look like tiny spiders having four pairs of legs, and a rounded, glossy abdomen in a variety of dark earth tones. Soil mites are decomposers, as well as predators. They feed mostly on decaying vegetation, but also eat springtails, round worms, and fungi.

Red velvet soil mite, *Trombidium sp*, by Alexey Nikodimov, Apr 2018

Pseudoscorpions, also called false scorpions, look like real scorpions without the dagger-like abdomen. They carry no poison, but have two large claw-like appendages in front. They are predators of springtails, soil mites, and certain worm species. Pseudoscorpions have no eyes or ears, living in the dark soil just below the leaf litter. Almost as numerous as springtails and soil mites, they depend on scent and vibration to locate their prey.

Pseudoscorpion by Philippe Garcelon, Mar 2021

Pseudoscorpion by Philippe Garcelon, Oct 2018

Other animal species that can be observed with either your eyes or a hand lends include ants and beetles. These two groups are quite diverse and can be found in all habitats and soil types.

Eastern Bess beetle larva, by Katja Schultz, Jul 2014

Ground beetles by Bernard DuPont, Feb 2006

Beetles make up the largest order of insects with over 300,000 known species. They can be found under decaying logs, under loose bark, and in the leaf litter. They are especially attracted to light sources at night. The larval stage of a beetle is called a grub, often found in shallow soil layers both on the forest floor as well as in our own backyards. Beetles feed on decaying vegetation, live roots, and other plant parts. They are a major food source for a variety of birds, mammals, arachnids, and other predatory insects.

Ants in bark by Michael Jefferies, Mar 2010

Ants are another insect group, forming vast colonies organized into social castes. There is a single queen in each colony plus thousands of workers and soldiers. Each individual has an appointed job serving the colony. Ants provide several ecological functions in any habitat: predators, scavengers, pollinators, recyclers, and soil aerators. Ant species are split into four groups identified as carpenter ants, little black ants, red ants and fire ants.

Forests are stopping grounds for many migrating species of birds, mammals, and insects. Forest litter is an excellent layer of insulation, and many of the species we have reviewed are active throughout the year, providing food for migrators and ecological services to the other year-round inhabitants. I encourage you to get out and observe this exciting habitat as you hike the forest paths this autumn.

Forest Litter, Critters to See

Last week, we started to look at the forest floor and the litter covering it, composed of leaves, dead wood, animal carcasses and other organic waste. A complex community of organisms thrives in this habitat, working to return the nutrients from the litter back to the soil to be used again as food for green plants. The first layer of this community consists of decomposers. This week, we investigate several other layers.

Forest floor & rotten log by DonArnold, Sep2022

Many species can be spotted among the litter, but observing them takes patience. Carefully sorting through leaf litter is a skill learned through practice. Overturning decomposing logs and probing through rotting bark will yield great results if done slowly and without great disturbance to the animals present. Animals can be observed with your eyes, a hand lens, or a microscope.

Using your eyes, there are several species that like moist conditions and are easily found under decaying logs. Many are very active after an autumn rain. Some of the more abundant species are:

Slugs are a type of mollusk with a soft, slimy body that leave a slime trail wherever they go on their nighttime feeding excursions. They eat decomposing leaf litter and animal remains.

Snail, Maple Grove by DonArnold, Sep2022

Snails, another mollusk, are covered with a hard shell for protection from predators and to help retain moisture. They also eat decomposing vegetation and animal remains.

Isopods, also known as wood lice or pillbugs, must have moist conditions because they breathe using gills. Often found under logs after a rainfall, they move quickly using their 14 pairs of legs. There are several hundred species found in field and forest habitats.

Pillbug, *Armadillidium vulgare*, by Dann Thombs, Dec 2010

Millipedes are segmented and covered by an exoskeleton. Feeding on litter and animal remains, they can be found in any slightly wet area. Millipedes protect themselves when threatened by rolling up into a tight ball.

Millipede, Maple Grove by DonArnold, Sep2022 (3)

Millipede defense, Maple Grove by DonArnold, Sep2022

Several species can be found in any litter conditions. Many are predators, hunting and feeding on other animals. Some often found in our forests include:

Centipedes may look like millipedes, but are predators, eating many smaller insects. The first pair of legs by their head are modified into sharp, poisonous claws used to capture and stun their prey.

Spiders have four pairs of legs, no antenna, simple eyes, and powerful jaws with poison glands. The injected toxin liquifies the soft tissues inside the victim’s body, allowing the spider to suck them out. Many species, including the popular wolf spider, are ground dwelling, digging burrows and hunting by night.

Paperbark spider, *Maratus pavonis* by Jean&Fred Hort, Sep 2015

Harvestmen, also known as daddy long legs, are similar to spiders. They have four pairs of very long legs. When disturbed, they will wave the front two pair around to ward off another predator. They feed on small insects and decaying plants and tend to hunt in groups, mostly at night.

Harvestmen, *Phalangium opilio*, by Dann Thombs, Sep 2007

Next we will investigate what a hand lens can reveal about some of the most numerous inhabitants.

Forest Litter

Autumn is a time of year when many changes take place in forests in northern Illinois. Leaves change color and fall off the trees; numerous species start their annual migration; and other species get ready to overwinter here. The forest floor forms a rich habitat, covered with several layers of litter including fallen leaves, dead wood, plant debris, exposed roots, and other organic matter.

Forest leaf litter by DonArnold, Sep 2022

Very few of the leaves that grow in a forest during spring and summer are eaten before they fall off the trees. A majority of the forest biomass litters the forest floor in autumn, providing a large amount of potential food for bacteria, fungi, and other decomposers living in the forest litter.

The top layer of forest litter contains newly fallen leaves. At lower levels, leaves and other debris become wetter. Small holes appear in leaves and around their edges, made by minute insects and mites. These allow bacteria and fungi to enter the interior of the leaves and begin the process of decomposition. As vegetation breaks down it becomes darker in color, and surfaces feel slimy due to the large number of microorganisms living on them.

Leaf litter with holes by DonArnold, Sep 2022

Skeletonized leaf by DonArnold, Sep 2022

Deeper in the litter, leaves have lost much of their soft tissue, leaving only veins and petioles. In bottom layers, leave are often unrecognizable. The organic matter has changed into dark, gritty, moist humus. Complex organic matter, once living, has been broken down to simple, non-organic chemicals and nutrients that are absorbed into the soil. Calcium, potassium, nitrogen, phosphorous, magnesium, and sodium are recycled from decomposing vegetation and animal remains.

Various fungi on rotting log by DonArnold, Sep 2022

Fungi feed on organic matter. Fungi are often not visible, either living underground or are microscopic in size. They produce fruiting bodies in the form of mushrooms, mold, and yeast. Fungal fruits are at the peak of their showiness after autumn rains. Fungi reproduce from spores, grown in the fruit, and released by wind, water, or contact with passing animals, to be spread throughout their habitat.

The most recognized fruits are the many mushroom varieties that appear in autumn. Mushrooms are most often grouped by physical characteristics. Some found in our area include:

Gilled mushrooms are pale white to highly colorful. They tend to grow from the ground or from decomposing stumps and logs, and may be poisonous. They are important field and forest decomposers by DonArnold, Sep 2022

Fleshy pore mushrooms come in many varieties, all having close relationships with specific tree root systems. They have pores instead of gills, loaded with spores under the edges of their caps.

Bolete mushroom by Jon D. Anderson, Oct 2014

Stinkhorns are pale white to red and sharply pointed. They produce a rotten odor to attract beetles and other bugs to spread the spores. They are commonly found among wood chips and decaying vegetation.

Stinkhorn by Yooperann, Jul 2012

Brackets grow by attaching to decomposing logs or tree trunks. They are dark red to deep brown and may grow singly or in clusters. They are hard and woody allowing them to a long time. Brackets by DonArnold, Sep 2022

Puffballs are round and light tan, tending to explode into a cloud of spores when hit by raindrops or falling debris.

Puffball by DonArnold, Sep 2022

Water-cup mushroom by Peter Stevens, Oct 2015

Orange-peel fungus by John Munt, Oct 2014

Cup fungi are brightly colored with upturned edges or deep furrows, such as morel.

Coral fungi grow mostly on logs and stumps. These appear as many branching structures with spores located in each branch.

Coral mushroom by Jim Bahn, Nov 2011

Chanterelles are light colored with wavy, upturned edges holding their spore.

Chanterelle by Sandra Cohen-Rose, Aug 2007

Jelly fungi are brightly colored, pale white to red. Although they appear to be shiny and slimy, they have a dry surface and a rubbery texture. They look like a clump of jelly or laid out in ribbons on branches and logs. Following a wetting from rain, spores appear on the surface to be lifted away by the wind.

On your next forest walk, be sure to watch for mushrooms along the trail, on fallen logs, and on tree trunks and branches. Next week we will take a closer look at what else may be living in the rich habitat beneath your boots!

Backyard Sounds

A peaceful afternoon, broken only by the sounds of…

As I sit on the back deck, I listen to the myriad sounds in the backyard. Bird, insect, and mammal visitors make daily forays among our many plants. We have bird feeders and fresh water available each morning.

Chipmunk eating serviceberry fruit by Brian Gratwicke, 2013

Robin in Amelanchier tree by Deb Nystrom, 2016

Cedar waxwing on serviceberry by John Matthews, 2018

Many backyard visitors including robins, chipmunks, cedar waxwings, and sparrows have been keeping close watch on the Amelanchier tree. Small green fruits appeared a few weeks ago, and ripened to a bright, cheery red after ten days. However, the birds did not wait that long to test the taste. Dozens of fruits ripen daily, but most are gone by the next day. Amelanchier, also called serviceberry, is a sub-family of the Rosaceae family. There are 28 species native to the United States. Small, deciduous, multi or single stemmed trees, they bear pome, a fleshy fruit with several seed chambers, that is a favorite for many species.

A cardinal has perched on the back fence next to our shade garden to “kip kip” at me about the lack of food. I feed the birds every year, providing thistle in a hanging net feeder, suet in a cage, and woodpecker mix in an open tray. Cardinals eat both early morning and late evening from the tray, but with the widespread reports of avian bird flu in May, we stopped feeding for several weeks. I am sure my friend has read the calendar and thinks the time is right for resuming putting his treats out!

Sawfly larva by Andy Reago & Chrissy McClarren, 2019

Next to the cardinal, the foliage on an elderberry in the back of the shade garden looks green and lush. This plant is a favorite food for sawfly larvae, which consumes the foliage leaving only the leaf ribs behind. A sawfly larva appears as a short, fat, white worm, and can be picked off by hand and thrown into a bucket of water to dispose of them. Be careful not to simply knock them off onto the ground, for they will quickly find their way back up the stems and into the foliage once again.

A natural pond surrounded by native forbs and grasses is at our yard’s back edge. Red-winged blackbirds are everywhere along the edges. This year we are watching two nests hidden deep in the foliage directly behind our house. Known for being aggressive birds during breeding season, they are being chased away by the cardinals. Cardinals are considered non-aggressive, but can be more than a match for the red-wing blackbirds when breeding territories between the two species overlap.

Another bird bothersome to the blackbird is the great blue heron that come to the pond for the small fish. Every time one shows up, the red-winged blackbird harasses it by flying directly at it and banging into it with a claw or beak. Male redwings rarely show signs of tiring while performing guard duties, and the herons may put up with this for several minutes, but eventually leave the pond.

A house sparrow family, living in one of the shade garden birdhouses, is making a racket to drive away a fox squirrel that has gotten too close to their nest. House sparrows are monogamous and mate for life. In the central U.S., two batches of four to five eggs are typically laid during the summer. In our birdhouse, the first batch of eggs hatched about a week ago. The young birds will remain in the nest for two to three weeks. During that time, the male and female share feeding and guard duty.

They meet…defense on their minds (DonArnold 2021)

I also hear bullfrogs calling, sounding a deep bass ‘jug-a-rum’ at any hour to attract a mate. There are several males in our pond, and as the summer heats up, and we have less rain, the pond gets a little crowded. Adults are solitary and a great splashing noise signals the meeting of two males, each aggressively defending their part of the pond. After mating, females lay 10,000 to 20,000 eggs in a gelatinous mass on the pond’s surface. Tadpoles hatch in four to five days, and those that survive will overwinter in the pond for one to two years before metamorphosizing into adults.

As the vanquished leaves… (DonArnold 2021)

Lakes & Ponds

Pond & lake observations on the trail

Walking trails in northern Illinois are found among many lakes and ponds. Over time, these bodies of water have formed and disappeared at varying rates, providing habitats for wildlife and vegetation.

Quiet mornings at the dock, Maple Hill, KS by RisingThermals, Aug 2021

Several types of water features were formed by the action of the last glaciers that left this area about 13,000 years ago. Kettle lakes were created when large blocks of ice, buried in the rocky edges of retreating glaciers, finally melted, leaving a hole filled with water. Surface lakes also resulted from glacial debris blocking off rivers and streams.

The Oxbow at The Wild Center, NY, Jun 2017

During heavy rainfall, some rivers collect enough water to force a new flow straight through the landscape leaving an older channel cut off into an oxbow lake. As rivers slow and shrink, beavers move in to dam them and create new ponds. Limestone lies under much of Illinois topsoil, dissolving slowly in running water, opening up sink holes that quickly fill to form new lakes.

Ponds and lakes constantly gain and lose water. Water comes in from rainfall, rivers and streams, groundwater, and springs. Water is lost through rivers and streams, groundwater aquifers, and evaporation. Incoming water often carries mineral and organic sediments, slowly filling in the basin. In areas where shorelines are not exposed to wind and wave action, seeds floating on wind and water will begin to take root.

Emergent wetland at Eugene Field by US Army Corp of Engineers, Jun 2014

Ponds and lakes come in many sizes, with shorelines that gradually recede to deeper water or fall off quickly. On the surface, water molecules are attracted to each other to form a firm layer between the water below and the air above. Some organisms use the top side of the surface layer to land on, float on, or run across. Insects, snails, and microorganisms hang off the underside of the surface layer. Where sunlight penetrates, water layers are teeming with single-celled green organisms providing an abundant food source for aquatic wildlife. Shallow lake bottoms support emergent plants, rooted in bottom soil and sending shoots above the surface for air and sunlight.

Cattails around the pond by Jemma Marycz, Jun 2016

Reeds at Keighley Tarn, by Tim Green, Oct 2009

Reeds, grasses, and other marsh vegetation colonize shorelines and shallow areas. Tall vegetation catches and traps wind-blown particles. Sediment comes in from streams and rivers running through the vegetation, gets filtered out and added to the soil layers. As more plants grow on the edges, and soil deposits become denser, woody shrubbery start to move in. Given time, in a natural process, existing lakes and ponds will become ever smaller.

Many lakes and ponds are affected by human activities, slowing down the natural cycle. Dredging and removal of edge vegetation reduces the amount of accumulated sediment. In urban areas, open ground that used to catch rainwater and allow it to slowly filter into wetlands is being covered with impermeable surfaces including roads, buildings, and parking lots. Increased runoff from these surfaces flows quickly into existing lakes and out again just as fast, keeping vegetation from getting an anchor.

Anderson Japanese Gardens, Rockford, IL by Jpellgen, May 2018

As you wander the trails, be sure to observe the differences in lakes and ponds of all varieties, and the many plant and animal species supported by each.

Turnover

Area ponds have been frozen for the last several weeks due to the extremely cold temperatures we have experienced. But, thawing started last weekend which initiates turnover, the mixing of pond water as surface temperatures change with the progression of the seasons. This process happens several times each year, and has profound effects on the insects, amphibians, fish and other wildlife that live in these waters year-round.

Water can exist as a gas, a liquid, or a solid depending on its temperature. Water density and its capacity for carrying oxygen also changes with temperature. Like most other liquids and gases, cold water is heavier, denser and can hold more oxygen than warm water. However, water has a unique property in that it reaches maximum density at 39˚F (4˚C). As water gets colder, it expands, becoming lighter weight and less dense. At 32˚F (0˚C), water freezes into a solid, crystalline structure called ice, which floats on top of the denser water below. This property makes it possible for wildlife to survive below the ice.

During summer, deeper bodies of water will have layers differentiated by temperature. The top layer is warmed by the sun and atmosphere and is the warmest, with layers getting progressively cooler as the pond gets deeper. Plant matter that falls in the pond will start the process of decomposition, using light and oxygen. As decomposing material sinks to the bottom where there is less light, this process can rapidly use all of the oxygen in the lower layers. Most animal life is found in the upper layers at this time of year.

Painted Turtle, *Chrysemys picta* by Steve Hinshaw

The top layer of water is constantly picking up oxygen from wind and wave action. As atmospheric temperatures start to drop in autumn, the top layer becomes colder, denser and able to carry more oxygen. As winter progresses and temperatures continue to drop, the denser, heavier water accumulates on the bottom of the pond. Aquatic species will move to this highly-oxygenated layer to spend the winter. In spring, as ice melts, the top layers of the pond pick up more oxygen from wind and wave action. As water temperatures at the surface start to climb, approaching 39˚F (4˚C), the layering effect may disappear for a short period as the entire pond mixes to a uniform temperature and density. Wildlife will start to move toward surface areas, finding well-oxygenated water everywhere in the pond. Layering will return as top layers warm more rapidly than underlying water.

American Bullfrog, *Lithobates catesbeianus* by James Harding

Northern Leopard Frog, *Lithobates pipiens* by James Harding

In Dupage County, Northern Leopard Frogs, Lithobates pipiens, American Bullfrogs, Lithobates catesbeianus, and adult Painted Turtles, Chrysemys picta, all spend the winter underwater. Painted Turtles burrow into the mud at the bottom. They slow their metabolism down to where they only need a small amount of oxygen each day. The blood vessels in their butts are very close to the skin, and they are able to absorb oxygen from the water directly into their bloodstream. They can remain in this state for 3-4 months. Northern Leopard Frogs and American Bullfrogs also slow down their metabolisms and have a similar ability to absorb oxygen through the skin into the bloodstream. They rest on the bottom, not immersing themselves in the mud because this would prevent the oxygen rich water from being in contact with their skin.

There are many factors that affect turnover and the availability of oxygen-rich water for the animals that overwinter under the ice. A mild winter may not freeze over the ponds, leaving the water well mixed and oxygenated throughout the season. Topography of the land surrounding a pond is very important. Open ponds that receive a lot of sunlight tend to turn over rapidly and often, and will have a shorter period under ice with lots of oxygen-rich water available. Ponds closed in by land or forest canopy will experience much less wind and wave action resulting in little turnover and smaller amounts of oxygen in the water. As spring starts to arrive, be on the lookout for changing conditions as wildlife starts to emerge.

Urban Wild

There are numerous animals in Illinois that have very successfully made the transition to living among people. Let’s take a look at a few that can be seen in the area as well as in our own backyards.

Striped Skunk, *Mephitis mephitis* by Phil Myers

The striped skunk, Mephitis mephitis, has some very noticeable characteristics, yet it is one of the least noticed mammals roaming our urban areas. Skunks have highly visible black and white stripes across their back and tail. Skunks are omnivores, eating both plants and animals including seeds, insects, small mammals and carrion. They are also opportunists with an excellent sense of smell allowing them to easily find pet food and bird seed put out by humans. While searching for grubs, one of their favorite foods, skunks can cause considerable lawn damage when tearing up grass in well-watered areas. They are nocturnal and have few natural predators. When threatened or attacked, skunks have the ability to spray an oily musk from two glands located near the base of their tails. A skunk can aim and spray up to ten feet, and the odor is pungent enough to be detectable up to one-and-a-half miles. Tomato juice neutralizes the odor and may help to remove it from clothes, hair and pets. Striped skunks are intelligent and usually good natured. Skunks have been sold as pets in some states, although Illinois is not one of those. They can live about seven years in the wild and up to ten years in captivity.

Red Fox, *Vulpes vulpes* by Kevin Castle

The red fox, Vulpes vulpes, lives in a wide range of habitats, and has been steadily moving into urban areas over the last 30-50 years. The red fox’s preferred habitat is open woodlands, but they will also reside in urban environments, especially those that are close to forest preserves or other wooded areas. They are omnivores, and their preferred prey includes fruit, rabbits, birds, mice and other small rodents. Their home range is 1 to 2 square miles, with most dens found in sunny woodland areas. Human habitation close to any wooded area such as large city parks, forest preserves or company campuses provide great hunting and feeding opportunities. Red fox are also moving into urban areas where there is less competition with coyotes for food as well as less likelihood of themselves becoming prey to coyotes.

The Raccoon, Procyon lotor, has been aggressively moving into city and suburban areas over the last 80 years. Studies at York University, Toronto, have shown that raccoons are very intelligent animals and able to learn to avoid the many dangers and obstacles found in a human dominated environment. They have five toes on their front paws, all of which are nimble and have great dexterity, allowing them to feel objects and learn how the object works. Raccoons are good at puzzle solving, providing ample opportunities for opening latches, entering garages, attics and pet doors, and getting into various food containers including trash cans, pet food and bird seed containers. They eat a wide range of food including insects, bird seed, trash, pet food, fruits, fish and bird eggs. Raccoons are nocturnal, active at night and sleeping most of the day. Raccoons can cause considerable lawn damage, digging for grubs and earthworms in well-watered areas. They can also be destructive in the home garden, consuming fruits and vegetables before they are fully ripe. Some of their favorites include corn, grapes and berries.

Bald Eagle, *Haliaeetus leucocephalus* by DonArnold

The Bald Eagle, Haliaeetus leucocephalus, a relative newcomer to northeastern Illinois, is found in large open patches. Bald Eagles have been seen in great numbers in Illinois for many years, but usually they are found during winter, feeding along the Mississippi River, one of their favorite flyways and a great source of fish through the colder months of the year. In the last twenty years, they have been observed in increasing numbers within the suburban areas of northeastern Illinois. Nesting pairs staying throughout the year have been documented in Palos Park, Lake Calumet, and Lake County as well as several other areas with large lakes. The many lakes and rivers in northeastern Illinois support large fish populations, providing an abundant food supply. Eagles’ preferred nesting sites are high up, in large trees, overlooking a favorite hunting area. There are many towns, parks and forest preserves with programs to save and preserve older trees and woodland areas, providing excellent nesting opportunities.

These are just a few examples chosen from many showing us how wild species living in this area for many years are adapting to humans. Trees, pollinator gardens, woodlands, open spaces, lakes, ponds, marshes and streams all play an important part in meeting our need for natural areas for recreation and aesthetics. These areas also support insects, small mammals, birds, amphibians, reptiles and larger animals, with a well-developed food chain and plenty of places to live in. Everyone can help maintain these patches of natural area at home by creating new habitat and protecting existing habitat on their property. Whenever you have an opportunity, work with city, county and state officials to improve public lands for wildlife.

Interconnected backyard habitat by DonArnold

Backyards provide year-round habitat for many smaller animals. Many species will spend an entire season in this area when summer and winter requirements are met. In addition, migratory species may use backyards for stopover points to rest and feed. Trees and shrubs provide cover for protection, resting spots for migration, and housing areas for seasonal or year-round inhabitants. Pollinator plants, trees and gardens, free of pesticides, provide a great variety of food for various species. Clean water, a necessity for all species, can be provided in an array of different ways including ponds, birdbaths, fountains, and streams. As more of these elements are connected together, such as several backyards comprising a larger area, these elements can provide habitat for a greater number of species for us to enjoy.

Summer Pollinator Bloom

It has been a couple of months since I shared a visit in our pollinator garden, and we were in the middle of a warm and wet spring which turned into a hot, dry summer. Now, it is mid-summer and a new set of flowers are in bloom and being heavily visited by a variety of pollinators including bees, wasps, ants and butterflies.

Grey Headed Coneflower, Ratabida pinnata, by DonArnold

Pale Purple Coneflower, Echinacea pallida, by DonArnold

Purple coneflower, Echinacea purpurea, by DonArnold

The coneflowers, members of the Aster family, are an easily recognized group of flowers. Grey-headed coneflower, Ratabida pinnata, grows a tall stalk, up to 4′, with a grey/green head of seeds surrounded by bright yellow, drooping rays. From the base of the flower moving upwards, seeds turn brown as they mature and are a favorite food for goldfinch. This species is also known for attracting many beneficial insects such as chalcid wasps, syrphid flies and minute pirate bugs, that keep harmful insects including caterpillars, sawfly larvae and various beetles under control. Purple coneflower, Echinacea purpurea, is a nectar source for monarch, red admiral and swallowtail butterflies. Considered a rare species in northern Illinois, it can grow up to 5′ tall. Flower heads are 2.5″-5″ in diameter composed of up to 20 purple petals surrounding an orange-brown array of disk flowers. A similar species is the pale purple coneflower, Echinacea pallida. Flowers are on single stems up to 3′ tall with pale purple petals that are skinnier and droopier than the purple coneflower. The center of the flower head is a dark brown array of disk flowers. More commonly found than purple coneflower, this plant is visited by a much greater variety of butterflies including American Lady, Red Admiral, Great Spangled Fritillary and Baltimore Checkerspot.

Black-eyed Susan, Rudbeckia hirta, by DonArnold

The black-eyed Susan, Rudbeckia hirta, is another member of the Aster family. Flowers are on single stalks growing to 3.5′ tall and are 2″-3″ wide with a dark brown, button-like central disk surrounded by 8-20 yellow, ray flowers. Historically, a tea was made from the leaves for treatment of common cold symptoms, and flower petals made be used to make yellow dyes. The plant is a food source for almost four dozen bee species in our area, providing both pollen and nectar. In addition, many species of wasps, beetles, true bugs and butterflies also feed on this plant.

Buttonbush, Cephalanthus occidentalis, by DonArnold

Eastern Tiger Swallowtail on Buttonbush, by DonArnold

Buttonbush, Cephalanthus occidentalis, a shrub commonly found in wet areas, hosts more than two dozen bird species in addition to bees, true bugs and butterflies. This shrub can grow from 3′ to more than 12′ tall, and likes moist to permanently wet soils. Flower heads appear as bristly balls on stalks attached to the main stem at the junction of leaf stalks. Each flower structure is about 1″ in diameter containing a nut-like fruit that stays on the shrub through most of the winter, providing a great food source for non-migrating native birds.

Common Ironweed, Vernonia fasciculata, by DonArnold

Common ironweed, Vernonia fasciculata, grows up to 6′ high and offers both nectar and pollen for insects. Flower heads form a dense cluster at the top of each stalk and are composed of 15-25 brightly colored purple disk flowers. Bees are able to see in the ultra-violet ranges, and the outer surface of the flowers reflect ultra-violet light, while the inner surfaces absorb it. This contrast makes the flower easy to locate for bees. Seeds are fluffy, brown and wind-dispersed. This plant is a host species for American Painted Lady butterflies and several additional butterflies that regularly visit for nectar including Easter Tiger Swallowtail, Monarch and Pearl Crescent.

Cardinal flower, Lobelia cardinalis, by DonArnold

The Cardinal flower, Lobelia cardinalis, provides a colorful contrast to some of the other plants at this time of year. An uncommon species, possibly due to its intolerance of areas with road salt, it can be found growing wild in woodlands, typically along stream beds. It is regularly visited by the Ruby-throated Hummingbird and Pipevine Swallowtail butterfly. The flowers are a brilliant red arranged in a long column from the top of the stem downward. These species will make a wonderful addition to any pollinator or perennial garden.