migration – 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.

Spring Migration

Meteorological spring starts Sunday, and we are already starting to hear the calls of early migratory birds, heading north from southern wintering grounds, working to establish territory their among the best nesting sites available.

Red-winged blackbird, Agelaius phoeniceus, singing by Rhododendrites, May 2023

Some birds, including red-winged blackbirds, Agelaius phoeniceus, get their cue to start spring migration as temperatures get warmer. These species head to prairies, forests, and wetlands to claim a location they can protect, call for a mate, and establish a nesting site with good protection and food sources. Other birds, including many warbler species, return in spring when daylight hours lengthen. Generally flying at night, they use star positions and the Earth’s magnet field to guide them. If nights are stormy or heavily overcast, early morning may find hundreds of them waiting in fields for clear skies. Birds may also stop for a day or two in areas located on the southern shores of any large body of water to rest and feed before crossing.

Red-winged blackbird, *Agelaius phoeniceus,* flock at sunset by Jerry Segraves

Bird species around the world generally follow established flyways, established routes over specific locations between their southern and northern territories. Many migration routes do not follow a straight path. Some species have historical stopover or feeding locations that provide a rest point along the way. Other species may not be able to cross a mountain range; or a large body of water can act as a barrier for land birds, but may be a required food source for wetland birds.

Arctic tern, *Sterna paradisaea*, adult & juvenile by Charles J Sharp, Aug 2025

Arctic tern, *Sterna paradisaea*, in flight by Charles J Sharp, Aug 2025

Long distance migration routes are most common for birds wintering in subtropical and tropical areas and breeding in the northern hemisphere. Long migrations in the southern hemisphere are far less common because there is less land near the South Pole to support breeding activities. The record holder for migration distance is the Arctic tern, Sterna paradisaea, overwintering in Antarctica and breeding in Arctic locations, a round trip between 30,000 and 55,000 miles. Some shorter migrations are between upper and lower altitudes in mountainous regions.

Penguin migration map by Fred Cooke
& Jenni Bruce, Aug 2011

Dusky grouse male, *Dendragapus obscurus*, displaying by US NPS

Most birds migrate in flocks, which reduces the energy needed to fly long distances and provides added protection against predators. Penguins migrate without flying. Most penguin species swim between locations, covering up to 1,000 miles round trip. A few species cover long distances on foot, including dusky grouse, Dendragapus obscurus, in the Rocky Mountains which walk from lower to higher elevations. However, a flock may encounter unfavorable weather or flying conditions that causes a large number of birds to stall in one location, introducing other risks including depleted food sources and predation by land-based animals.

At the Jurica-Suchy Nature Museum, we host a nature walk every other week to observe changes in our campus including the birds that are moving through the area. There are many birding groups worldwide that provide opportunities to observe and learn about migratory birds in every location. Consider joining a group, or take your own bird walk as we have clear days and warming temperatures and see who’s on the move in your area.

Sounds of Spring

Thunder and heavy rain, soft rain and light wind, birds in the early morning, frogs in the evening, and maybe a coyote howl deep into the night are some of the sounds of spring. As cold temperatures ease into summer highs, walks through natural areas tend to be filled with many sights as well as opportunities to learn by being quiet and listening closely.

Calls and songs are used by many species for a variety of purposes. Thousands of birds are migrating through the area, especially on clear evenings, and calls help to keep birds together and establish who is the flight leader. Year-round species are re-establishing territories, using calls to warn intruders to stay away or warn family members of approaching threats. Frog species in particular are calling during evenings to find a mate, lay eggs, and begin the establishment of the next generation.

There are dozens of species active at this time of year, and as we have been taking nature walks on campus the last few days, here are some of the wildlife we are listening to (click on each picture to hear their call)…

^{Yellow-rumped warbler, Setophaga coronata, Mirceax, Getty Images}

Yellow-rumped warbler, Setophaga coronata, by Valerie Heemstra, 2024

^{Red-winged blackbird, Agelaius phoeniceus, by KenCanning, Getty Images Signature}

Red-winged blackbird, Agelaius phoeniceus, by Thomas Ryder Payne, 2022

^{Palm warbler, Setophaga palmarum, by Irving A. Gaffney, Getty Images}

Palm warbler, Setophaga palmarum, by Christopher McPherson, 2021

^{Northern waterthrush, Parkesia noveboracensis, by Carol Hamilton, Getty Images}

Northern waterthrush, Parkesia noveboracensis, by Lance A.M. Benner2017

^{Northern Parula, Setophaga americana, by Neil Bowman, Getty Images}

Northern Parula, Setophaga americana, by Richard E. Webster, 2023

^{Chipping sparrow, Spizella passerina, by Irving A. Gaffney, Getty Images}

Chipping sparrow, Spizella passerina, by David Tattersley, 2023

^{Blue-headed vireo, Vireo solitarius, Mirceax, Getty Images}

Blue-headed vireo, Vireo solitarius, by Thomas Magarian, 2024

^{Blue Jay, Cyanocitta cristata, by Miguel Opacic, Getty Images}

Blue Jay, Cyanocitta cristata, Sue Riffe, 2024

Bird songs have a structure and rhythm, and are repeated often to attract a mate, ward off rivals, or bond with a family member. Other calls give warning that danger is near, keep flocks together in flight, or create a pair bond, often between mother and chick.

Frogs and toads are mating and laying eggs in area ponds. Each species has its own distinctive call, used by the males to attract a mate, warn of potential danger, establish a territory, or to signal distress. Frog species being heard around campus at this time include the following (click on each picture to hear their call)…

^{American Toad, Anaxyrus americanus, by Mshake, Getty Images}

American Toad, Anaxyrus americanus, by Thomas Margarian, 2024

^{Boreal chorus frog, Pseudacris maculata, by Derwyn, Getty Images}

Boreal chorus frog, Pseudacris maculata, by Thomas Margarian, 2016

^{Spring peeper, Pseudacris crucifer by HuntImages, Getty Images Signature}

Spring peeper, Pseudacris crucifer by Paul Marvin, 2012

^{Northern Leopard Frog, Lithobates pipiens, by Jennifer Seeman, Getty Images}

Northern Leopard Frog, Lithobates pipiens, by Paul Marvin, 2015

Sometimes, coyote can be heard when walking in woodlands around campus late in the evening. There are a lot of different calls used by these canines to provide information to other individuals. You can listen below to a bark used to indicate a threat, a social call establishing an individual’s location, a begging call from a young one, and a howl audible over long distances to announce one’s presence. Other calls may include a woof to signal a low intensity threat, a yip to claim territory, a growl to threaten another animal, and a whine or yelp to show subservience to a more dominant individual.

^{Coyote, Canis latrans, barking by TakenPix, Getty Images}

Coyote, Canis latrans, bark by Paul Marvin, 2018

^{Coyote, Canis latrans, begging, by Keith Szafranski, Getty Images Signature}

Coyote, Canis latrans, begging call by Matthew L. Brady, 2025

^{Coyote, Canis latrans, social interaction by Michel Viard, Getty Images}

Coyote, Canis latrans, social call by Flor Sangermano, 2023

^{Coyote, Canis latrans, howling, by Keith Szafranski, Getty Images Signature}

Coyote, Canis latrans, howl by Paul Marvin, 2012

Additional wildlife sounds can be heard on campus around Lake Benedictine or in nearby forest preserves. Get out for a walk and be sure to listen throughout the day for bird species, and into the evening hours for frogs, toads, and coyotes.

Bird Song

As spring approaches, many bird species will be migrating across the country from warm winter sites back to summer nesting areas to mate and raise young. For many bird watchers, a favorite activity is to identify birds by their songs. Songbirds have an organ called the syrinx that produces the lyrical notes we can listen to. Birds may produce one or more notes at a time creating complex calls and melodies. Some of these songs are used to attract a mate, or to identify itself to another family member, or as calls of warning about any approaching danger. Night traveling species may use calls to keep the flock together while flying, but most calls are heard throughout daylight hours.

In the upper Midwest, in prairie and wetland areas, the first migrators in early March will include ruby-crowned kinglets, blue-winged teals, loggerhead shrikes, upland sandpipers, and eastern bluebirds. As night time temperatures become warmer and stable, summer tanagers, Baltimore orioles, and up to 35 warbler species will begin moving through this area. Some species to watch for in northern Illinois are American white pelicans, common loons, Northern pintail ducks, and yellow-bellied sapsuckers.

You can find many excellent observation spots in your area by searching online for “spring birding hotspots in your area”. Another favorite forecasting site to follow migrating bird groups is the University of Cornell’s BirdCast Project website.

American white pelican, Pelecanus erythrorhynchos, by Manjith Kainickara, Nov 2010

Call from a young chick by Andrew Spencer, XC36292

Baltimore oriole, Icterus galbula, by Tony Castro, May 2013

Alarm call by Joost van Bruggen, XC864040

Call by Gus Mueller, May 2007

Blue-winged teal, Spatula discors , by Alan D. Wilson

Call by Jonathon Jongsma

Common loon, Gavia immer, by John Picken, Jul 2011

Tremolo call by Darwin Long, Apr 2006

Eastern bluebird, Sialia sialis, by Sandysphotos2009, Apr 2010

Call by Jonathon Jongsma, Jun 2011

Loggerhead shrike, Lanius ludovicianus, by Jeffrey Gammon, Dec 2020

Alarm call by Bobby Wilcox, XC418584

Call by Ed Pandolfino, XC455607

Northern pintail, Anas acuta, by J.M. Garg, Jun 2007

Call by Paul Driver, Feb 2012

Pied-billed grebe, Podilymbus podiceps, by Mdf, 2005

Begging call by José Dellacasa Bravo, XC946741

Nocturnal flight call by David Tattersley, XC811994

Pair contact call by Richard E. Webster, XC971465

Ruby-crowned kinglet, Regulus calendula, by Tony Castro, Jun 2019

Call by Christian Kerihuel, XC814137

Sandhill crane, Grus canadensis, by Jeffery Gammon, Jan 2017

Call by National Park Service, Jan 2004

Left: Summer Tanager female, Piranga rubra, by Gonzalo Zepeda Martinez, Jan 2016

Right: Summer Tanager male, Piranga rubra, by Charles J. Sharp, Feb 2023

Call by Lance A. M. Benner, XC426315

Upland sandpiper, Bartramia longicauda, by Johnath, Jun 2010

Call by Andrew Spencer, XC104334

Yellow-bellied sapsucker, Sphyrapicus varius, by Rhododendrites, Feb 2021

Call by G. McGrane, 2006

At the Jurica-Suchy Nature Museum, our nature journaling club, Nature-Doodlers, will be meeting on March 29th, 10am, at the museum to learn about bird observations, drawing and recording our sightings. Make a reservation to come out to this free event by clicking on the QR Code below:

Insects Over Winter

It is starting to get chilly in the Midwest as we head toward winter. Insects also recognize the shorter daylight hours and dropping temperatures. They use two main strategies to cope with winters: freeze avoidance and freeze tolerance. Avoidance may require travel or a dry place to stay warm. Tolerant insects can stay here and control their body’s response to freezing temperatures. Staying in place has several advantages including being able to emerge early in spring, allowing those insects to feed before predators are out.

^{Clockwise from upper left: Monarch butterflies on migration by Dopeyden, Getty Images; Cecropia moth cocoon by Sylvie Bouchard, Getty Images; Milkweed bugs by Rick Wood, Rick Wood’s Images; Four-lined plant bug, Poecilocapsus lineatus, by Heather Broccard-Bell, Getty Images Signature; Common pill-bug by Ines Carrara, Getty Images}

Those insect groups that opt for traveling to warmer climates often make a one-way trip. Monarchs are one of the best known insect migrators. Monarchs east of the Rocky Mountains leave in early fall to arrive at overwintering sites in the mountains of Mexico. Their offspring return to the southern U.S. in spring to breed, and this second generation returns to the East and Midwest over the following summer. Monarchs west of the Rockies overwinter in Baja, California, and many of the same individuals that fly south do return, but their trip is considerably shorter allowing time for breeding during summer months in the northwest U.S.

^{Honeybees in hive by OK-Photography, Getty Images}

Many different species of insects can control or stop ice formation in their bodies. Honeybees cluster together and shiver, generating enough body heat to keep the air above freezing in their hive. Other insects get rid of all the food and water in their bodies, becoming dehydrated and unable to freeze. Some species can control where ice crystals may form in their bodies, and prevent their formation inside cells that would cause harm to the insect. Insect species that retain some water use cryoprotectants, chemicals resulting from large amounts of sugar. One such chemical is glycerol, which lowers the freezing temperature of water and other liquids.

^{Dragonfly larva with fish by Mauribo, Getty Images Signature}

^{Fast running stream by Mburnham, Getty Images}

Some insects remain active throughout the winter. Aquatic insects in immature stages can easily spend the winter in fast moving or deeper water that does not freeze. Some insects move inside warm and protected places like attics, sheds, and gaps in house walls. They also overwinter in tree cavities, under bark, inside dead plants, and in old burrows. Allowing vegetation with hollow stems to stand through the winter will provide many populations a safe place to spend the season.

The insect version of hibernation is called diapause, when growth and development is halted until longer daylight hours prevail. Late winter weather patterns with warm periods interspersed with cold periods endanger many species. Another change we have experienced in recent years involves warm temperatures lasting later in fall and starting earlier in spring. These changes interrupt the historical natural cycles, causing insects and other animals to abort hibernation and actively look for food or mates. Food plants do not produce enough to support animal populations, or another cold period returns, and species are not able to adapt, and often perish.

^{A garden in winter by Vermontalm, Getty Images; Snag and deadwood in winter by BayDavn0211, Getty Images; Spring garden and returning insects by Anthony Lerma, Getty Images}

Insects are a vital part of healthy habitats, providing pollination services and food to many species. We can help overwintering insects by leaving dead stalks standing until late spring to provide safe habitat. Leaves left piled up provide nutrients, insulation, and a place of shelter. Uncovered soil can also host ground nesters such as native bees. Snags and logs provide lots of cavities protected from the weather. Selecting some plant species that bloom early or late in the year will provide additional food at those times. Growing plants in clusters enables insects to find all they need in one place. With a little planning, everyone’s backyard can be an inviting habitat for insects year-round.

Baleen Whales

There are over 90 species of whales roaming every ocean habitat. There are two broad classifications of whales, baleen whales and toothed whales. Baleen whales lack teeth. When they open their mouths, a membrane made of keratin, called baleen, stretches from the upper to the lower jaw. This allows water to flow through its porous structure while trapping fish and zooplankton, small sea creatures, by the mouthful. Toothed whales have actual teeth and they hunt fish, squid, and other animals of the sea.

^{Clockwise above- Baleen by Paigefalk, Getty Images Signature; Humpback whale (baleen) by Craig Lambert, Getty Images; Orca whale (toothed) by Schmid-Reportagen, Pixabay}

There are 15 species of baleen whales compared to 77 species of toothed whales. Baleen whales are generally larger, with the blue whale being the largest whale in our oceans. Most baleen whales are migratory, moving between cold, polar waters that support large populations of prey and warmer waters that they use for breeding. While warm water environments support less prey, they have fewer predators and other risks, allowing newborn youngsters to grow and learn to defend themselves before migrating back to richer feeding grounds.

Humpback mother & calf by Lauren Baer, Getty Images

Consider the Sei whale, one species of baleen whale from the Rorqual family that is known for their slender, pointed heads and fins. They are one of the smallest baleen whales, growing to about 40′ in length as an adult. Exact population numbers are not known, but it is estimated there are about 60,000 Sei whales worldwide. Each Sei whale eats about one ton (2,000 pounds) of food each day, including krill, fish, and squid. One ton holds close to a half million krill, a small crustacean weighing about 2 grams. The entire population of Sei whales alone is consuming roughly 20 billion krill or other small fish each day!

Group of Antarctic krill by Noyan Yilmaz

Baleen whale eating by Julian Allchin, Getty Images

Whales, hummingbirds, humans, frogs, and rabbits are all tetrapods, animals whose ancestors had legs. Nearly all of the bones in one species can be found in each of the others, a condition called homology. This is the result of divergent evolution where organisms from the same common ancestor evolve and accumulate differences, often resulting in an entirely new species. These differences are selected based on both biotic and abiotic factors in the habitat. Whales have the same shoulder-arm-hand structure inside their side fins as a human arm. While our hands and arms let us reach, grasp, and throw an object in the air, a whale’s fin delivers a powerful push through the water they live in.

Whale fin to human arm bone structure homology by DonArnold, 2024

^{Humpback pushing with fin by Yann-Hubert, Getty Images Pro; Human arm throwing a ball by South Agency, Getty Images Signature}

At the Jurica-Suchy Nature Museum, you can observe and learn more about homologous structure from our Sei whale / human arm skeleton comparison. Plus we have more to show you concerning whales and other marine species from around the world. Read more about whales on the following sites:

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.

Hummingbirds

It is getting to the end of summer, and many bird species that winter in Central and South America will soon be starting their migrations. Of the 320 species of hummingbirds, 15 spend the summer breeding in North America, from the Gulf Coast states to southern Canada, before returning to winter habitat farther south. Only one species, the Ruby-Throated Hummingbird, Archilochus colubris, breeds east of the Mississippi River.

7 of the 15 hummers that breed in North America:
- Anna’s Hummingbird, Calypte anna, by Alan Scmierer-USFWS, Mar 2007
- Black-chinned Hummingbird, Archilobus alexandri, by Paul Crook-USFWS, Jun 2024
- Blue-throated Hummingbird, Lampornis clemenciae, by Alan Schmierer-USFWS, Jun 2024
- Broad-billed Hummingbird, Cynanthus latirostris, by Alan Scmierer-USFWS, Mar 2022
- Buff-bellied Hummingbird, Amazilia yucatanensis, by Alan Scmierer-USFWS, Jan 2010
- Broad-Tailed Hummingbird, Selasphorus platycercus, by Tom Koerner-USFWS, Feb 2024
- Allen’s Hummingbird, Selasphorus sasin, by Wendy Miller-USFWS, Jun 2024

Hummingbirds have a very high metabolism with a normal heart rate of 250 beats per minute that accelerates to almost 1250 beats per minute when in flight. They consume large amounts of nectar each day to get enough sugar to support their energy requirements. Several small grooves running the length of their tongue funnel nectar into their throat by capillary action, a force that causes liquid to rise in a small tube without needing to use air to suck the liquid in. They also eat any small invertebrate to fulfill protein, vitamin, and mineral needs. Hummingbirds snatch insects mid-air while in flight, poach them from spider webs, and glean tiny moth caterpillars from new leaves and branch tips. Another foraging method uses the blast of air beneath their powerful wings to roll over leaves on the forest floor, revealing the insect life below.

^{Anna’s hummingbird catching insects by Stan Lupo, Jul 2023}

Hummingbirds do not bond with a mate. Females establish a territory that optimizes the available nectar and offers multiple nest sites. Males establish a territory based on encountering as many females as possible. Both will defend their areas from other hummingbirds, as well as other nectar feeders including butterflies and bees. Daily feeding starts on the outer edge of their territory to chase out any overnight interlopers and ends with nectar sources deep inside the area’s interior. Males will breed with as many females as possible. Females may have more than one brood of eggs each year, either concurrently or one brood following another.

Nests are about 2″ in diameter, built of small twigs, lined with soft plant material, and covered on the outside with greenish-gray lichens. Nests are bound to branches with spider silk, usually in a forest clearing. The lichens provide camouflage by making the nest appear as a large knot when seen from below. Females reach breeding age at the end of their first year, and can breed throughout their lifetimes. They construct one or more nests, each containing two white eggs, the size of peas, which are incubated by only the female for 14 to 16 days. The male takes no part in raising the young birds, coming together with the female only during mating.

^{Allen’s Hummingbird nest, by Mike’s Birds, Mar 2013}

^{Ruby-throated hummingbird on nest with lichen, by Lorie Shaull, Jul 2020}

Hummingbirds found in the western portions of North America travel overland migration routes. However, midwestern and eastern birds fly non-stop over the Gulf Of Mexico. A hummingbird can increase its fat reserves and double its body weight in the 7 to 10 days prior to the overseas trip. Through studies using banded birds, we have learned that they fly alone, normally at night, along with large flocks of other birds. Young birds, making the trip for the first time, can successfully navigate the migration route with no prior training. Their guidance system, how it works, and how it is learned are all still a mystery.

No hummingbird species are listed as endangered. However, hybridization among species is common, and their small size and great speed make them very difficult to count and track. Little data is available about population size changes and movements; however, more birds have been found over-wintering as far north as the Gulf Coast states of North America.

At the Jurica-Suchy Nature Museum, we have numerous bird specimens on display, including hummingbirds. We welcome you to come in and learn more about these amazing creatures.

Remaining 8 species that breed in North America:
Calliope Hummingbird, Selasphorus calliope, by Barbara Wheeler-USFWS, Nov 2021
Costa’s Hummingbird, Calypte costae, by Wendy Miller-USFWS, May 2020
Rivoli’s Hummingbird, Eugenes fulgens by Doug Greenberg-USFWS, Aug 2017
Lucifer Hummingbird, Calothorax lucifer, by Jim Gain-USFWS, Mar 2022
Ruby-throated Hummingbird, Archilobus colubris, by Alan Scmierer-USFWS, Jun 2024
Rufous Hummingbird, Selasphorus rufus, USFWS, Jun 2024
Violet-crowned Hummingbird, Amazilia violiceps, by budgora, Mar 2014
White-eared Hummingbird, Basilinna leucotis, by Alan Scmierer-USFWS, Mar 2022

Extinct & Endangered – pt.2

The International Union for Conservation of Nature (IUCN) gathers data through research and field projects on all known species of plants and animals. They work to educate people on conserving nature and sustainably using natural resources. The IUCN publishes a document known as The Red List providing the conservation status of all species. There are nine possible levels including Least Concern, Near Threatened, Vulnerable, Endangered, Critically Endangered, Extinct in the Wild, Extinct, Data Deficient, and Not Evaluated.

An endangered species is one that is likely to become extinct in the near future, either world-wide or locally in a known range. Critically endangered species are at extreme risk of extinction in the immediate future. A species is vulnerable when its population and breeding numbers are at risk, but have a chance to improve. Several factors considered are the current population size, how fast the population has increased or decreased over a short period of time, whether breeding rates are high or low, and what threats exist from habitat loss, poaching, and invasive species.

^{Eskimo curlew, Numenius borealis, @ Field Museum of Natural History by James St. John, Oct 2014}

The Eskimo curlew, Numenius borealis, spends northern hemisphere summers breeding on the Alaskan and western Canadian tundra. As the weather turns colder, they migrate to Argentina by flying east to the Atlantic Ocean, and then south. Although nests are built on open ground, they are difficult to find and study. Food includes berries, insects, and snails, but incubation and rearing habits have never been clearly identified. During migration in the mid-1800s, populations would darken the skies as tens of millions of birds followed the warmer weather. Eskimo curlews were hunted on both continents year-round. If a bird was wounded, the other flock members would circle back, becoming additional targets for hunters. Development cuts up large breeding areas to smaller sections reducing food sources and enabling predators to severely impact populations. The species is listed as critically endangered, although there has not been a confirmed sighting since 1963.

^{Proboscis Monkey, Nasalis larvatus, by Chris Smallwood, Jul 2013}

^{Proboscis Monkey, Nasalis larvatus, female with young by Martha de Jong-Lantink, Jun 2020}

The proboscis monkey, Nasalis larvatus, another endangered species, is found mostly in the mangrove forests in Borneo; it is one of the largest monkeys native to Asia. Living in swamps and lowland areas along rivers, they are excellent tree climbers and swimmers, having the ability to swim underwater for short distances. Their large noses, smaller in females and upturned in juveniles, are thought to make their calls louder and more attractive to the opposite sex. They communicate through a variety of calls to signal alarm and threat warnings, and to keep infants and group members close. Rapid loss of habitat to logging and oil palm plantations, plus hunting for their meat, considered a delicacy in some areas, have reduced populations by more than half in the last fifty years.

^{Whooping Crane, Grus americana, by Trish Gussler, May 2018; Whooping Crane, Grus americana, by Diana Robinson, Mar 2018; Whooping Crane, Grus americana, by Evangelio Gonzalez, Dec 2018}

The whooping crane, Grus americana, is one of only two crane species native to North America, and it remains on the list of endangered species although it may be starting a comeback. Birds build a nest on a slight rise in a marsh where one or two eggs are laid. Normally only one egg survives, and the juvenile stays with the parents for six to eight months. Populations were never large, but prior to European settlement, there were an estimated 10,000 birds. Hunting for meat and feathers, in addition to predation and habitat loss, drastically reduced population size from the mid 1800s to the early 1900s. Through several programs of captive breeding, wetland management, and extensive efforts to assist the juveniles in learning migration routes by following ultralight aircraft, populations have rebounded to about 600 today.

^{JSNM Extinct Endangered display; JSNM Eskimo curlew, Numenius borealis; JSNM Proboscis monkey face, Nasalis larvatus; JSNM Proboscis monkey, Nasalis larvatus; all pictures by DonArnold, Feb 2024}

In the final blog on this topic, we will take a look at a few success stories – species that have recovered with populations that continue to get stronger. Many nature museums have information and extinct species on display to learn from. All of the above species, and more, can be found at the Jurica-Suchy Nature Museum, so please stop by, or visit a local nature museum where you live.

Sea Turtles

Sea turtles live in every ocean environment around the world, nesting on tropical and subtropical beaches, and migrating long distances. They spend their entire lives at sea except when females come ashore to lay their eggs. They have been on earth for over 100 million years, surviving the period when most dinosaurs and other reptiles died out 65 million years ago.

^{Coral reef & hawksbill sea turtle by jakubgojda, Indian Ocean, Maldives}

Sea turtles are large, air-breathing reptiles with upper (carapace) and lower (plastron) shells. Six of the seven species are covered by hard scales called scutes. Although none have teeth, jaws are suited to each species specific diet. Sea turtles do not have ears, but there are eardrum openings covered by a flap of skin. Their sense of smell is excellent as is their underwater vision, although they are nearsighted when out of the water. Along with a streamlined body, they possess powerful legs and claws for swimming, diving, and catching food.

^{Green turtle eating seagrass by LauraDin, Getty Images}

^{Green sea turtles, Chelonia mydas, on coral reef by Artush, Alam, Egypt}

Sea turtles, along with manatees, are excellent caretakers of seagrass beds and coral reefs, habitats that are vital to the reproduction of fish, shellfish, and crustaceans. Seagrass, one of their favorite foods, grows faster and stronger with daily trimming from turtle munching. Coral beds, vulnerable to collapse and suffocation under mass quantities of sponges and small crustaceans, benefit from sea turtles that eat several hundred of these animals each day.

^{Olive ridley digging egg chamber by JHVEPhoto, Getty Images, Costa Rica}

^{Green sea turtle hatchlings by Penny Britt, Getty Images}

After reaching sexual maturity, which takes from 15 to 50 years, depending on the species, female sea turtles return every two to five years to the beach where they were born to lay their eggs. On average, they dig three to seven nests and place about 100 eggs in each. Baby sea turtles break out of their egg and instinctively flee for the lighter colored horizon where the ocean meets the beach. They spend several years in the open ocean feeding and growing before venturing into shallower waters to eat, mate, and reproduce. Only about one in a thousand babies will grow to be an adult. Most are prey for birds, crabs and fish, but many are killed by humans for food, medicines, and religious ceremonies. Nesting site habitat destruction and turtles caught as part of the fishing industry also play a part in population decline.

^{Jellyfish & jacks by melissaf84, Getty Images, Coral Sea; Whelks by Pack-Shot, Getty Images; Reef crab by JohnAndersonPhoto, Getty Images, Lembeh Strait, Indonesia; Posidonia seagrass meadow by Arnaud Abadie, Getty Images Signature, Mediterranean Sea}

Females lay all of their eggs on land, but nesting sites and the best feeding sites may be thousands of miles apart. Sea turtles are found throughout the world’s oceans following concentrations of jellyfish, sponges, and crustaceans found in coral reefs and seagrass beds. Leatherback females have been tracked making migrations of over 12,000 miles between nest sites and the best annual feeding grounds during non-breeding seasons.

Read facts on each species in the sidebar, shown below. Come to the Jurica-Suchy Nature Museum where we have loggerhead, hawksbill, and green sea turtles on display to learn more about these creatures and their hidden realms.

^{Pics 1&2: Green sea turtle, Chelonia mydas, by DonArnold, JSNM 2023; Pics 3-6: Hawksbill sea turtle, Eretmochelys imbricata, by DonArnold, JSNM 2023; Pic 7: Loggerhead sea turtle, Caretta caretta, by DonArnold, JSNM 2023}

Sea turtle species…

There are seven species of sea turtles in the world. All are experiencing dwindling populations from various threats. Two are critically endangered: the hawksbill sea turtle and the Kemp’s ridley sea turtle. Two are endangered: the green sea turtle and the flatback sea turtle. Three are listed as threatened: the leatherback sea turtle, the olive ridley sea turtle, and the loggerhead sea turtle.

Hawksbill sea turtles, Eretmochelys imbricata, have a narrow head allowing access to tight spaces in coral reefs, the usual spot to find sponges. They consume 1,000 pounds of sponges annually, keeping coral reefs free from suffocation by the sponges. These turtles are medium size at 2′-3′ and 100-200 pounds. Females nest on beaches among rocky areas 3-4 times in a season and lay 140-200 eggs in each nest.

^{Hawksbill portrait, Eretmochelys imbricata, by Sheraca, Dec 2014; Hawksbill sea turtle, Eretmochelys imbricata, by Goug Finney, Sep 2019}

Kemp’s ridley sea turtles, Lepidochelys kempii, are the smallest species at 2′ in diameter and 75-100 pounds. Kemp’s ridley turtles have made a huge recovery from the 1960s, when there were about 200 individuals left, to almost 9,000 today. This is due to changes in Mexico’s laws, where 95% of their nesting takes place, to protect nest sites from disturbance.

^{Kemp’s ridley sea turtle, Lepidochelys kempii, by USFWS, Sep 2010}

Green sea turtles, Chelonia mydas, grow to 4′ and 500 pounds. They are herbivores with a finely serrated beak for biting seagrass and scraping algae from hard surfaces. This is the only species known to come onshore to bask in the sun. They are named for the color of their fat, not their shell.

^{Green sea turtle, Chelonia mydas, by Florida Fish&Wildlife}

Flatback sea turtles, Natator depressus, have a flattened carapace, unlike other turtles. They are medium sized at 3′ and 200 pounds. Found only in Australia, they do not migrate. Females lay only about 50 eggs in a nest, but nests are well spread out, helping to better protect their eggs. Their biggest threat is being preyed upon by saltwater crocodiles.

Leatherback sea turtles, Dermochelys coriacea, are the largest species at 4′-8′ and 500-2,000 pounds. They consume mostly jellyfish, daily eating their own weight in food. They have no scutes, but are covered by a flexible, leathery skin that allows them to dive up to 4,000 feet deep searching for prey. These turtles have thermoregulatory adaptations that allow them to hunt in very cold waters from Alaska to Chile, and they regularly make the longest migration of any vertebrate animal, traveling over 12,000 miles annually.

^{Leatherback sea turtle, Dermochelys coriacea, by Claudia Lombard, USFWS, Jun 2011}

Olive ridley sea turtles, Lepidochelys olivacea, are small at 2′ and 75-100 pounds. They are the most abundant of all species. On certain beach sites, nesting females form an arribada, a grouping of all the females offshore who all come ashore at the same time to nest and lay eggs. Females on other sites may nest alone. Arribadas are particularly vulnerable to mass mortality events, but these are rare and population numbers remain consistent.

^{Olive ridley sea turtle, Lepidochelys olivacea, by Charles Peterson, Head Start Programs, Oct 2002}

Loggerhead sea turtles, Caretta caretta, grow to 4′ and 200-400 pounds. Their very large heads and jaws can easily crush hard shells, allowing them to eat crabs, conches, and whelks. They have the largest concentration of nests annually, including 30,000 at a single Mediterranean location. Their shells provide space for 50 to 100 epibionts: plants and invertebrates that live permanently attached to their shells.

^{Loggerhead sea turtle, Caretta caretta, & epibionts by actor212, Aug 2017}

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

Bird Migration

Migration began in early September and is just passing the peak period with several millions of birds in flight every night. Migration is defined as a seasonal and predictable event that is repeated annually. Other types of movements for bird populations include dispersal, occurring when a bird leaves the place where it was raised to find a mate, and irruption, occurring when a group of birds leave a site because winter is so harsh they are forced to move to find food.

Insect eater Eastern Kingbird, Tyrannus carolinensis, by Dennis Murphy, Jun 2016

Neotropical ruby-throated hummingbird, Archilochus colubris, by Rick-from-Alabama, Jun 2013

Migration requires that many species move hundreds of miles or more across and between continents. There are high risks involved, so why do birds leave a territory they have established a home in to go elsewhere for a portion of the year? Insect eating birds must move south in winter as food sources die off in significant numbers in northern regions when temperatures drop. Neotropical species require constant warmer temperatures. Many birds that spend the winter in equatorial belts move north in spring to take advantage of abundant summer food supplies and fewer nest predators including parasites. These birds must migrate south in autumn to remain in seasonally warm weather.

Golden eagle, Aquila chrysaetos, soaring on Seedskadee NWR by USFWS Mountain-Prairie, Jan 2014

Blue jay, Cyanocitta cristata, in flight by Jo Zimny, Jan 2019

Many species fly at specific times during a twenty-four hour period. Thermals, upward moving columns of air, are created by the sun. Soaring birds including sandhill crane, golden eagle, and turkey vulture flying during daytime hours, depend on thermals to get airborne and remain aloft. Some daytime species are dependent on food sources that are only out in warmer, daytime air. For birds that do not ride the air currents, including blue jay and white-crowned sparrow across the northern United States, using powered flight generates much body heat, which is easily compensated for by cooler nighttime temperatures. Nighttime air is also less turbulent, making the flight smoother and requiring less energy.

Junco, Junco hyemalis, by Colin Durfee, Mar 2020

Migration distance varies widely among species and even within one species. In winter in northern Illinois, we often see dark-eyed juncos, Junco hyemalis, on our backyard feeders. This species breeds in summer in northern Canadian regions. Studies show that young males migrate only a short distance to southern Canada, while adult females migrate the greatest distance to the southern U.S. Adult males and young females migrate several hundred miles to winter in north-central regions. Observations of young males show they are first to stake out new territories in the spring for breeding. Adult males are aggressive enough to establish a territory upon their return. Adult females can arrive later to find a mate with an already established territory. And young females are simply learning the routine until they grow older.

Canada geese, Branta canadensis, in V formation by Floris van Halm, Jan 2010

Winds at flying altitudes are the main factor in determining whether a day’s travel will be long or short and use lots of energy or only a little. Strong headwinds reduce flight speed by up to half and require more energy. Strong tailwinds speed the flyer along with less effort. Birds that fly in flocks have more advantages. As air flows around a bird in flight, it is deflected upwards from the wingtips. Birds flying in a “V” formation, such as Canada geese, use the air coming off their neighbors wings to make their flight easier and use up to 40% less energy. As you watch a formation, notice the lead bird gets no energy savings but changes position every few minutes with another bird, so each takes a turn at the leader’s position.

Research in recent years has contributed to many sites having online tools for monitoring and learning about all aspects of migration. For fun facts and up-to-date information, take a look at:

Migration Dashboard (birdcast.info) shows migration information including dates, birds, counts, and routes by U.S. state or county.
Bird Migration Explorer (explorer.audubon.org) from Audubon shows maps of current migration activity.