defensive strategy – 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.

Great Horned Owls

The great-horned owl, Bubo virginianus, is native to much of the Americas, including most of North America and Central America and about half of South America. It is the second heaviest owl in North America, right behind the snowy owl, Bubo scandiacus, weighing up to five-and-a-half pounds with a wingspan between three and five feet.

^{Great-horned owl, Bubo virginianus, by Andy Reago&Chrissy McClareen, Aug 2012}

^{Range and distribution of Great-Horned Owl, Bubo virginianus by BirdLife International, 2014}

Feathers cover the entire body, including their feet, and are varying shades of browns and grays. Their backs and heads are mottled or barred in several patches. This coloration, especially when coupled with mostly nocturnal activities, provides excellent camouflage. Their ‘horns’ are actually feathers sticking upwards on either side of their heads. These are called plumicorns, but their function is not well understood. The feather structure of the wing allows owls to fly silently and includes a serrated leading edge to disrupt turbulence and softer feathers behind to help deaden sound.

^{Great horned owl plumicorns by Jean-pol Grandmont, Aug 2013}

^{Great horned owl wing structure by Peter K. Burian, Aug 2015}

The owl’s ears are covered by feathers, but are not symmetrical with one being higher on the side of the head than the other. This arrangement provides the owl with the ability to triangulate sounds and precisely locate prey in the dark or when prey is hidden, such as when an animal is moving about under a layer of snow. Their flattened face, shaped as a round disc, also helps to direct sound to their ears. Like all owls, their eyes are fixed in the sockets, but the bird can swivel its head almost 180° to either side allowing it to see in all directions.

^{Great horned owl talons by Curtis Bouvier, May 2010}

Great horned owls hunt from a perch, observing the area below them before diving swiftly and silently from far above. Their diet consists of small mammals, birds, amphibians, and a variety of snakes. Their talons are powerful and deadly, with a grip comparable to much larger birds such as golden eagles. Most prey is killed by being pierced or crushed in the talons. Owls may hunt and kill for more than their immediate needs and will cache their kills for future meals.

Great horned owls are not migratory. When an owl is ready to mate, courtship occurs in late fall and pairs mate for life, establishing a territory together in which they will live their entire lives. Most territorial defense is through hooting at a transgressor, but rare physical confrontations have been observed. If an owl cannot establish its own territory, it will live in silence among the fringes of other territories.

^{Great-horned owl juveniles, Bubo virginianus, by Alan Vernon, Jun 2010}

^{Great horned owl female & juvenile on nest by John Kees, Apr 2012}

Males are responsible for picking a nest site, almost always taking over a nest constructed by another species. Mated pairs breed once every two to three years, laying from one to six eggs. Egg laying occurs between late February and early April. The female alone incubates the eggs, never leaving the nest, while the male hunts and brings her food. After about 33 days, the eggs hatch. Young owls will start to fly after seven weeks, but take a full month or more to become proficient.

^{Great horned owl calling, Bubo virginianus, by Michael & Katie LaTour, Jan 2019 (at 0:02, 0:10)}

^{Great-horned owl pair calling by Bushman, Dec 2013 (at 0:18, 0:41, 0:51, 1:22)}

Owls are more often heard than seen. Although the females are larger than males, females have a smaller voice box and thus a higher pitched hooting call ending with a slight rising note. Juveniles can make hissing or screeching sounds and are often misidentified as barn owls, Tyto furcata.

You can learn more about these magnificent birds at the Jurica-Suchy Nature Museum. Make a reservation to come see us by visiting our website at: https://ben.edu/campus-links/jurica-suchy-nature-museum/ (click on Register to Visit the Museum).

Fancy Hair

Hair is a structure that is unique to mammals, growing from small organs called follicles found just under the outer layer of skin. Hair can be modified into different forms providing insulation, camouflage, signaling, sensing movement, and for use in defense.

^{A scanning electron microscope image of human hair showing keratin layers, by CSIRO, Oct 2008}

The hair shaft extends above the surface of the skin. It is formed from layers of a protein called keratin. When bundled together, the layers form strong and hardened strands. There are more than 50 types of keratin that together form hair, nails, outer skin layers, claws, hooves, horns, plates, and baleen. Many keratin proteins are combined with varying amounts of an amino acid called cysteine, that provides additional strength and hardness. Let’s investigate some forms of hair that help keep mammals protected.

Left: Armadillo scutes encapsulating their body by DonArnold, 2025; upper right: Armadillo showing arrangement of scutes and plates covering their body by DonArnold, 2025; lower right: Southern three-banded Armadillo, rolled into a ball, by MiraianeDL, Getty Images

An armadillo has a tough shell encasing the sides and upper parts of its body. The shell is composed of solid pieces covering hips and shoulders and bony plates in between. The entire shell is covered with scutes, small scale-like structures made from hair flattened into a tough, leathery layer protecting the outside of the shell. The bands form a flexible pattern that allow the animal to move quickly with very few of the softer body parts exposed. The three-banded armadillo of South America can roll up into an almost impenetrable ball with only the scutes exposed.

^{Pangolin searching for ants by 2630ben, Getty Images}

^{Pangolin lies rolled into a ball by Khlongwangchao, Getty Images}

The pangolin looks similar to an armadillo, and although they are not related, they do possess similar features. Pangolins can also roll up into a tight ball. Their tail, covered with sharp-edged scutes can be left outside the ball and used to lash out against potential predators. However, being smaller animals, this form of defense provides almost no protection against their greatest threat – humans. They are the most trafficked mammal in the world, hunted for their meat which is served as a delicacy in many parts of the world. Their scutes are also in high demand by cultures for medicine and by leather goods industries.

Mammalian spines and quills are two other structures formed from hair. Quills have a hardened outer covering, and a soft, spongy core, and are found in porcupines, echidnas, and some rodents. Spines also have a hard outer covering of keratin, but consist of solid layers of hair inside. Both structures are generally straight and rigid, and may be sharply pointed, with or without a barb at the end.

Porcupines have quills with sharp tips and a backward facing barb near their ends. Porcupines cannot shoot a quill at an attacker, but if the attacker comes into contact with any of the quills, their sharp ends easily penetrate skin. Quills are brittle and often break off after being embedded, and the barb makes them difficult to remove, resulting in a painful experience for an aggressor that gets too close.

^{Hedgehog rolled into a ball by Tchara, Getty Images}

Hedgehogs are known for their spines, which are all the same length, not barbed, and do not come out easily. They are more like prickles, providing a pointed reminder to an aggressor not to get too close. A hedgehog can roll into a ball with all of the spines projecting outwards, making it very difficult to grab or bite the animal without being pricked any number of times.

^{Echidna, aka Spiny Anteater, by DonArnold, 2025}

At the Jurica-Suchy Nature Museum, you can learn about these defense tactics, as well as those of other species and how they provide for their own safety. Make a reservation to come see us by visiting our website at: https://ben.edu/campus-links/jurica-suchy-nature-museum/ (click on Register to Visit the Museum)

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.}

Salamanders

Salamanders are in the order of amphibians named Caudata, which includes mudpuppies, newts, and sirens. There are about 760 species of salamanders worldwide and 121 species are endangered. With the exception of a few in the Amazon basin, they are found only in the northern hemisphere. They live in habitats that provide sufficient humidity levels to keep their skin moist, from sea level to nearly 15,000 feet in altitude.

^{Northern zig-zag salamander, Plethodon dorsalis, by John P Clare, 2016}

^{Marbled salamander, Ambystoma opacum, by Jupiterimages, PhotoImages}

The smallest species are lungless salamanders of southern Mexico, growing to an inch in length. The largest species are the Chinese great salamanders, about six feet in length. They are often mistaken for lizards, having smooth or bumpy skin, but can be easily identified by their total lack of scales. All salamanders have a tail which is rounded in terrestrial species but slightly flattened and often crested in aquatic species. Most salamanders are grey, brown, or white, but a few terrestrial species are brightly colored. Cave dwelling salamanders often lack all pigment and appear pinkish-white in daylight.

^{* Western lesser siren, Siren intermedia nettingi, by Peter Paplanus, 2013}

^{Long-tailed salamander, Eurycea longicauda longicauda, by Meghan Alessi, Getty Images}

Salamanders, other than cave-dwellers, tend to have well-developed eyes. Research shows they are very attuned to differentiating brightness, but cannot see colors. Their eyes are large and provide nearly 360 degrees of view. Salamanders have no external ears, but can detect vibrations received through their jaw bones. Although some species can emit small squeaks, salamanders have no vocal chords or voice box and do not use vocal communications. Their sense of smell is well-developed and plays an important part in locating prey and mates.

^{* Hellbender, Cryptobranchus alleganiensis}
^{alleganiensis, by Jason Ondreicka, Getty Images}

^{Cave salamander, Eurycea lucifuga, by Alfred Crabtree, 2012}

Salamanders may have functional lungs, non-functioning lungs, or no lungs. All species have the ability to exchange gases directly through their skin and the membranes inside their mouth and throat, but this also requires that the skin remain moist at all times. Terrestrial salamanders depend on moisture found in deep leaf litter, holes in trees in temperate zones, or moisture collected in bromeliads growing on trees in tropical zones.

^{Four-toed salamander, Hemidactylium scutatum,}
^{by Jason Ondreicka, Getty Images}

Salamanders have three sets of glands located under the skin, covering their entire body. Mucous glands secrete a sticky liquid that is spread over their body keeping the skin from drying out. When salamanders are in the water, the mucous acts as a lubricant, enhancing their swimming ability. A second set, called the granular glands, produce toxins and odors unique to each species that helps to deter predators and attract mates. A third set of glands is a mixture of the first two, doing a little bit of the work of each.

^{Small-mouthed salamander, Ambystoma texanum,}
^{by Jupiterimages, PhotoImages}

^{Tiger salamander, Ambystoma tigrinum tigrinum, by John P Clare, 2013}

Salamanders are not as noticeable as many other species. They prefer secrecy and out-of-the-way hiding places. Most species are active at dusk and into the nighttime. All salamanders are carnivorous, feeding on small crustaceans, insects, spiders, and their favorite food – worms. Predators include snakes, lizards, fish, birds, and small mammals. Salamanders defend themselves by exhibiting threatening poses and emitting toxins, many with a bad odor. As a last defense, they may voluntarily lose their tails to a predator, a trait known as autotomy. A new tail can be grown within a few weeks.

Salamanders are easy to care for and their habitats are easily duplicated making them widely distributed in the pet trade and for use in laboratories. Additional conservation impacts come from habitat fragmentation, or habitat degradation, or habitat loss due to draining of wetlands and forest clearing.

^{Northern slimy salamander, Plethodon}
^{glutinosus glutinosus,}
^{by Jason Ondreicka, Getty Images}

^{Red-backed salamander, Plethodon cinereus cinereus, by Steve Byland, Getty Images}

In Illinois, we have 20 species of salamanders, pictured throughout this blog. Seventeen are terrestrial and three are aquatic (*). Consider coming to the Jurica-Suchy Nature Museum or a nature museum near you to learn more about salamanders in your area.

Spotted salamander, Ambystoma maculatum, by Louisianatreefarmer, Getty Images
Blue-spotted salamander, Ambystoma laterale, by Jason Ondreicka, Getty Images
Central newt, Notophthalmus viridescens louisianensis, by Andrew DuBois, 2016
Dusky salamander, Desmognathus fuscus conanti, by Jason Ondreicka, Getty Images
* Mud puppy, Necturus maculosus maculosus, by Andrew Hoffman, 2010
Three-toed salamander, Amphiuma tridactylum, by Peter Paplanus, 2016
Southern two-lined salamander, Eurycea cirrigera, by Peter Paplanus, 2021
Mole salamander, Ambystoma talpoideum, by Andrew DuBois, 2016
Dark-sided salamander, Eurycea longicauda melanopleura, by Andrew Hoffman, 2010

Ostrich

The ostrich, the largest and heaviest bird, is one of the handful of birds that cannot fly. They live in arid and semi-arid habitats in Africa, as well as in a small population of once captive birds that were released into the wilds of Australia. Several sub-species of the common ostrich, Struthio camelus can be found across most of Africa, while the Somali ostrich, Struthio molybdophanes, is only found in the far east around the Horn of Africa.

^{Common ostrich, Struthio cameus, Tanzania by Patrick Gijsbers, Getty Images Signature; Female Somali ostrich, Struthio molybdophanes, in Kenya by Ninara, Dec 2013; Male Somali ostrich, Struthio molybdophanes, in Kenya by Christiaan Kooyman, Jan 2003}

Ostrich males, called roosters, are predominantly black and can grow to 9′ and 180 pounds, while the slightly smaller females, called hens, have grayish-brown feathers and top out at about 6′ and 240 pounds. They live 30-40 years in the wild. Ostrich eyes, at almost 2″ in diameter, are the largest eyes of any land animal. Their species, camelus, refers to their long necks, large eyelashes, long legs, and their ability to go without water for extended periods.

Birds that can fly have many strong flight muscles attached to their sternum, which is shaped like a keel, an elongated structure which is narrow at the top and flares out at the bottom. However, the sternum of the ostrich is flattened and their wings are quite small. They do have powerful legs that allow them to sprint over 40mph and run long distances at an average speed of 31mph. Their long legs can cover 10-16 feet in a single stride. They only have two toes with one having a long claw that can dig into the ground for extra traction.

Notice the flattened sternum on the lower right of the ostrich compared to a flying bird below with a much larger bone.

^{Above: Flying bird shows large keel for flight muscles by LeeLiyi, Jun 2006}

^{Left: Ostrich skeleton, Museum of Veterinary Anatomy, FMVZ USP Wagner Souza e Silva, Dec, 2015}

Ostriches live in small family groups called herds. An average herd is about a dozen birds, led by one dominant male and one dominant female, called pack leaders. When males are ready to breed, they make a booming sound using an air sac in their throats that can be heard over long distances. When a female approaches, the male will puff out his chest, bow to the female, and do a dance that includes much tail shaking. This is repeated several times until the female indicates whether or not she will mate.

Ostrich eggs in shallow sandy depression, Namibia, by Th Trede, Getty Images

A dominant male digs a shallow nest 9 to 10 feet wide and mates with several females. Each mating results in 7-10 eggs laid together in the one nest. Ostrich eggs are the largest of any egg in the world weighing about 3 pounds, equal to 2 dozen chicken eggs. One male and one female will take turns incubating about 20 of the eggs, while the remaining eggs are ejected from the nest. Babies hatch in six weeks and are the size of a chicken when born, but they will grow about a foot a month, reaching adult size in six months.

Ostrich toes & claws by Mirko Vuckovic, Getty Images

Ostriches are omnivores mainly eating roots, seeds, and leaves, but will also eat insects, rodents, and snakes. They lack teeth; and as with many birds, they ingest small pebbles to help grind their food in the stomach. They are most vulnerable when eating or protecting their nests, and predators include lions, cheetahs, hyenas, and jackals. When threatened, an ostrich will not bury its heads in the sand. The bird may lie down on the ground with its head and neck stretched out to present a lower profile. They may run away, but if that is not possible, especially when protecting a nest, they will stand their ground. Their legs and sharp claws are powerful enough to deliver a kick capable of killing an adult lion. Many predators will not attack an adult ostrich, but their eggs are a delicacy for predators, vultures and other opportunists.

Many farms raise these birds, harvesting feathers and leather for clothing, plus meat and eggs for food. Although they are not considered endangered, ostriches are still threatened by habitat loss and poaching. At the Jurica-Suchy Nature Museum you can view an adult ostrich, nest and eggs, plus see our new display on the skeletal structure of birds including our adult ostrich skeleton.

Cicadas

Cicadas are found in habitats with deciduous trees on every continent except Antarctica. There are about 3,000 species worldwide; and 170 make their home in North America, including several species divided into three groups with 13-year or 17-year life cycles, found exclusively in the eastern and central United States. The map below shows where various groups are located.

Cicadas hatch from eggs laid in tree branches. After dropping to the ground and burrowing into the soil, they spend the majority of their lives as a nymph living underground. Using their rostrum, a long, sharp rigid structure that can penetrate the outer layer of tree branches and roots, they feed on the sugar and water flowing through the xylem tissue of the tree. Species classified as annual cicadas actually live from one to nine years, some emerging each summer. They are active for four to six weeks to mate, lay eggs, and then they die.

Look closely to see the rostrum sticking out in front of the nose

Magicicada after emerging from final molt by Karly Tuminello

Cicadas have wide set eyes, short antennae, and large, clear wings with membranes clearly visible. The surfaces of their outer wings are covered by small, blunt, waxy spikes. They are water repellant, keeping the insect dry. These spikes can also break up and kill any potentially harmful bacteria landing on the surface.

^{Magicicada species showing short antennae & clear wings by Karly Tuminello}

Beneath the wings are muscular structures called tymbals which can be flexed creating a sound like banging a drum. The buzzing sound commonly associated with cicadas is a result of rapidly flexing these muscles. Tymbals are found on both sexes, and are used to hear sound as well as produce sound. Males often form large groupings to enhance their sound and attract more females to a single location.

Magicicada waiting for wings to harden after molting by Karly Tuminella

Nymphs start to emerge when underground soil temperatures are above 64⁰F, usually in late May in the northern hemisphere. Males emerge about two weeks before females. After emerging, the nymph will find a suitable perch and molt to reveal a fully winged adult; then spend from one to six days waiting for their wings to harden. Males fly up into nearby deciduous trees to find a suitable mating perch and begin calling to attract a female, which will join the male after her molt is complete. After mating, the female lays about 600 eggs. She cuts 25 to 30 small slits in branches and deposits about 20 eggs in each where they will remain for six to ten weeks before hatching. Both sexes may mate several times with different partners, although most only mate once.

Cicada’s mouth parts are strong enough to pierce tree bark, but they do not bite or sting, although they may pierce human skin if handled roughly. They do not pose any danger to humans and have not been known to carry any harmful disease. They feed on sap, not foliage, so they pose no threat to mature trees. Younger or smaller trees with only a few branches may be overwhelmed by the many slits made by a female laying a full brood of eggs. Lots of slits may cause scarring that could kill smaller branches.

^{Empty cicada husks provide food for many species by Karly Tuminello}

Cicadas and their empty husks do provide food for many predators including birds, fish, mammals, herps, and other insects. The emergence of the periodical cicadas will provide a feast for their predators, whose populations will boom next year before being reduced by less available food over the following several years. One theory for why there are periodical species concludes that cicadas emerging in mass numbers can overwhelm the predators need for food, allowing a great number of cicadas to breed and maintain their own high population. Other theories also exist to explain this natural phenomenon, but whatever the reason, they are harmless insects with a very interesting life cycle for us to observe this year.

Extinct & Endangered – pt.3

An endangered species is one that is likely to become extinct in the near future, either worldwide or locally in a known range. In some instances, these species may be saved through habitat conservation, breeding assistance, and education. This final installment on Extinct & Endangered will take a look at three species in North America that have benefited greatly from such efforts.

The Gila Monster, Heloderma suspectum, is the only venomous lizard native to the United States and is listed as near threatened. Their ranges are quite small, covering 700 to 3000 square feet. They spend most of their lives in underground burrows, and they are only regularly outside for a couple of hours each day during their mating season, from March to May. Gila monsters hunt small animals, and prey is eaten alive, head first. Venom is delivered through their saliva as the prey is chewed and acts to slow the prey’s reactions. While venom is not deadly to humans, it can cause swelling and severe pain.

^{Gila Monster, Heloderma suspectum by Erin Donalson, Getty Images}

^{Gila Monster, Heloderma suspectum by Shoemcfly, Getty Images}

Gila monsters pose no direct threat to humans, usually living in remote areas, but still have a fearsome reputation that contributes to illegal hunting of the species. They were the first venomous animal in the United States to get legal protection from being collected, killed, or sold. As development threatens areas where the Gila monster is found, conservationists are moving populations to preserves where there is minimal interactions with humans. Breeding numbers in the wild are still robust, although captive breeding efforts have been started in zoos across North America. Education and preservation of appropriate habitat has so far kept this species off the endangered lists.

The black-footed ferret, Mustela nigripes, is listed as endangered, but increasing in population. Their native range includes southern Canada and the northern United States, but habitat loss and disease have reduced populations to only a few hundred. They are a playful member of the weasel family, using several vocalizations for communication including barks, chattering, and chuckling. They are nocturnal and rarely seen in the daytime. Prairie dogs, hunted in underground burrows at night, are their exclusive food source.

^{Black-footed ferret, Mustela nigripes, portrait by Delecrouix, Getty Images Pro}

^{Black-footed ferret, Mustela nigripes, at prairie dog burrow by kahj19, Getty Images}

The species was declared extinct in the late 1960s until a dozen individuals were found in Wyoming in the early 1980s. Deliberate extermination of prairie dog colonies, because they are considered a nuisance species, has had a significant impact on black-footed ferret populations. Habitat protection and captive breeding programs have been successful at boosting population numbers. There are now about 300 black-footed ferrets living in Wyoming and other sites in the north central and southwestern United States where individuals have been released. Habitat loss and disease are still constant threats, and scientists estimate that about 3,000 individuals will be required to save the species from extinction.

The California Condor, Gymnogyps californianus, the largest bird in North America, formerly nested in caves in high cliff faces along the southern California coast until real estate development claimed all of their habitat. In the 1980s, as the last 34 birds were captured, the species was declared extinct in the wild.

^{California Condor, Gymnogyps californianus, tagged, in flight by OldFulica, Getty Images}

Condors are slow flyers, soaring in great circles, searching for carcasses of dead animals to eat. They eat until they are full, and can go about two weeks between meals. Juveniles may take several months to learn to fly and land gracefully, without crashing. Condors reach reproductive maturity at four to six years of age, and can live over fifty years. After mating, females lay only one egg, and mating may not take place every year.

^{California Condor, Gymnogyps californianus, Grand Canyon by Blewulis, Getty Images Pro}

Even with slow reproduction rates, efforts to expand the population by hand-rearing and re-introduction to unaffected habitat have resulted in close to 450 birds back in the wild in California, Utah, Arizona, and the Baja. Still listed as an endangered species, the California condor is making great progress in rebuilding its population.

^{California Condor, Gymnogyps californianus by DonArnold, Mar 2024}

^{Introduction to Extinct & Endangered at Jurica-Suchy Nature Museum by DonArnold, Mar 2024}

Extinct and endangered species can be found in every habitat and location worldwide. Many are being helped by direct action with hand-rearing and habitat protection. Indirect action through new laws, conservation support, and education has also had a positive effect. Many of these species are on display at various nature museums including the Jurica-Suchy Nature Museum. Plan a visit soon to learn more.

Snake Defense

Snakes, with over 3,000 species worldwide, are one of the largest groups of reptiles. They are found on every continent except Antarctica and live in every type of habitat including freshwater and saltwater. They have numerous enemies and have developed defensive strategies enabling them to survive and prosper.

^{Catching a snake on the wing by CuriousLog, Jun 2007}

^{Red-shouldered hawk with snake by Don Loarie, Mar 2018}

^{Great Blue Heron eating snake by C Watts, Jan 202}2

Snakes must deal with threats from a wide range of animals. Bird species that prey on snakes include raptors, ravens, egrets , and storks. Nocturnal hunters, including owls, have excellent sight in low-light conditions and often hunt by spotting movement among foliage. Likewise, during daytime hours, red-tailed hawks and eagles can spot movement on the ground while soaring. Snakes are normally line-of-sight hunters, and are often unaware of threats from above, giving avian predators a distinct advantage.

_{^{American crocodile, Crocodylus acutus by Florida Fish and Wildlife, Feb 2021; Wolverine by Maia C, Aug 2012; Skunk by D Fletcher, May 2016}}

Most mammal predators are larger, more agile, and faster. Badger, wolverine, and racoon are all excellent climbers and may hunt from an elevated perch. Wolverine and skunk are also burrowers that will dig out their prey from underground. Snakes living in saltwater and freshwater environments are eaten by predators such as crocodiles and snapping turtles. In addition, some larger snake species regularly hunt smaller snakes.

^{Copperhead on dead leaves by Abbott Handerson Thayer, Mar 2022}

Snakes use a number of non-aggressive strategies to avoid confrontation and escape. Their best defense is to remain hidden, using colors and patterns to break up the outline of their body, allowing the snake to blend with the background foliage and be overlooked by any predators. Another passive strategy is balling, involving compressing their body into a tight coil or ball, typically with the head tucked in to protect this most vulnerable area. Playing dead is often an effective means to escape predation, honed to perfection by the Western hognose snake. This snake convulses its body, rolls onto its back, and lets its tongue loll out of its mouth. It may vomit or spew blood, release fecal matter or musk, all in its attempt to convince a potential predator that it is already dead and no longer appetizing.

^{Timber rattlesnake balled and hidden by Peter Paplanus, Apr 2022}

Mimicry is a development that has taken place in some species over long periods of time. Batesian mimicry is when a harmless species has evolved the coloration of a more dangerous species to fool a predator into leaving it alone. Scarlet kingsnakes of the southeastern United States are quite harmless but look very much like Eastern coral snakes, a venomous species in that same area. Auditory mimicry involves creating sounds used by more dangerous snakes. Fox snakes, found in deciduous forests, often vibrate their tails in leaf litter, making a buzzing noise very similar to the sounds made by rattlesnakes living in the same area.

^{Scarlet kingsnake by FWC Fish & Wildlife Research Institute, May 2015}

^{Eastern coral snake by FWC Fish & Wildlife Research Institute, Sep 2014}

Snakes often use one or more methods of intimidation. Bright display colors are found among many venomous species and serve as a warning to potential predators that this snake is dangerous. Another form of intimidation involves a snake inflating its body or a body part to make it look bigger. The puff adder inflates its whole body by filling its lung with air. Cobras hold their heads high and flare out an extra fold of skin on either side of their heads, commonly called “hooding.” Intimidation may also involve auditory cues including the rattling of a snake’s tail and the hiss emitted by cobras as they bring up their heads.

When the above strategies do not allow the snake to escape, most species will not hesitate to strike. Several species do not bite, striking with the nose or an open mouth; however, all venomous snakes will bite in self-defense, although they may not inject venom. A few species are able to spit venom, used purely as an act of self-defense, although if the venom targets an eye or nasal passage, the results can be extremely painful.

Snakes are some of the most interesting species with a lifestyle very different from our own. They have many strategies for keeping themselves safe from wild predators, and will be around for us to observe, learn about, and be fascinated by.

Creepy Critters

A lot of creepy critters are starting to show up in my neighborhood as Halloween approaches. Many people are putting out scary pumpkins, bats, spiderwebs, and spiders. There are about 3,000 species of real spiders in North America, and all spiders have fangs that inject venom used to paralyze or kill their prey.

Spider web house by Stephanie Wallace, Oct 2007

Spiders are normally quite timid and must be threatened or provoked before they will attack a species larger than themselves. All spiders will bite, but most species do not have teeth that are large enough to break human skin. Of those that can bite through our skin, only four species dangerous to humans are found in North America. They belong to two groups, the widow spiders with three species in North America and the recluse spiders with eleven species in North America.

Widow spiders are all commonly called black widows, but they are actually three different species located across North America and include the western species, Lactrodectus hesperus, the northern species, Lactrodectus variolus, and the southern species, Lactrodectus mactans. In northern Illinois, the northern widow is a small species between 1/8″ and 3/8″ long. Males have long abdomens with white and red markings while females have more rounded abdomens with a red hourglass marking on their underside.

Northern black widow, *Lactrodectus variolus*, male by Judy Gallagher, May 2018

Northern black widow, *Lactrodectus variolus*, female by Andrew Hoffman, May 2012

Widow spiders are shy and tend to remain hidden under logs and stones, or just inside entrances to animal burrows. During autumn, as temperatures drop, they will move inside if possible and are often encountered under furniture, boxes, or discarded items that are not often disturbed. Webs are funnel-shaped and provide for adults and eggs. Once eggs are laid, the female will rarely leave the eggs untended, and will aggressively protect them from all harm, attempting to bite anyone that disturbs her or the eggs.

Black widows tend to flee rather than bite, unless they are protecting eggs. Only the females bite and their venom is especially dangerous to humans, but bites are not painful and may not even be noticeable at first. Severe stomach cramping develops within an hour or two and breathing may become difficult. Despite the uncomfortable effects, black widow bites are lethal in less than 1% of cases.

The brown recluse, Loxosceles reclusa, is the most widespread of the recluse spiders, and is often found in or around human dwellings. Other recluse species are found in very limited areas. Their favorite outdoor spots are under boards, stones and log piles, but they are most often found inside in quiet areas on the floor or behind furniture. Adult spiders are a light yellow-brown with a dark violin-shaped marking on their back. Adults are between 1/4″ and 1/2″ long with long, thin legs that can be three to four times the length of their body.

Brown recluse, *Loxosceles reclusa*, by Mike Keeling, Jan 2008

Recluse spiders are not aggressive and will only bite when disturbed. Most bites occur when the spider is caught in an article of clothing that is picked up off the floor, startling the spider. Once bitten, the wound develops a crust with a red zone around it. The crust may fall off rather quickly but leaves a crater behind that may take several months to fully heal. Although their bite may cause tissue damage, there have been no confirmed deaths in the United States.

Halloween is a special time of year and can be a fun time with scary creatures and other haunts. The Juricha-Suchy Nature Museum is hosting its 13th annual Creepy Critters Halloween Open House on October 26th (for info, please call (630) 829-6546 or email JuricaSuchyMuseum@ben.edu). I hope you get out for some trick-or-treating of your own, and let the real spiders live quietly in their own habitats.