predator – Discover-Nature

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.

Bird Beaks

Beaks or bills? Two interchangeable words naming the horny part of the jaw of a bird. They have numerous uses including gathering food, feeding, preening, and display, and are often used for functions that would be accomplished by arms and hands on other animal species. Let’s take a closer look at their structure and how birds use them for feeding.

Beaks come in a variety of sizes, and most are proportionate to the size of the bird’s head. Two or more of the bones comprising the lower jaw in birds are often fused together, increasing the strength of the overall structure. Birds do not have teeth, allowing the jaw bones to be lightweight, making it easier for a bird to hold its head out in front of its body while flying.

^{Barn owl, Tyto alba, skull showing fused jaw bones by Didier Descouens, Jul 2010}

Beaks are made from bone covered with keratin, a structural protein providing strength and rigidity. Yet beaks have some flexibility which adds to their dexterity when in use. The inner surface of the keratin layer is constantly growing while the outer surface is equally being worn away by use. Both upper and lower jaws are jointed where they attach to the skull, allowing for extended movements including the ability of a bird to open its jaws wider than most other animal species.

^{Great white pelican, Pelecanus onocrotalus, by Craig Adam, Feb 2013; Red-headed woodpecker, Melanerpes erythrocephalus, by Mark Moschell, May 2016; Evening grosbeak, Hesperiphona vespertina, by Fishhawk, Feb 2021}

A beak is specialized for every species depending on diet and food gathering methods. Cone-shaped beaks, found among cardinals, grosbeaks, and finches, can trap, cut, and crush seeds. Scoop-shaped beaks allow skimmers, spoonbills, and pelicans to slide their lower jaw under slippery prey, then catch and hold onto it . Beaks tipped with a chisel-like point are used by woodpeckers probing into crevices in hard materials. Along with a reinforced skull, keratin reinforces the beak’s toughness, standing up to repeated hammering and prying movements.

^{From upper left: Blue-gray gnatcatcher, Polioptila caerulea, by Dave Wendelken, Jul 2023; Pied flycatcher, Ficedula hypoleuca, by Edward Anderton, Jun 2012; Ruby-throated hummingbird, Archilocus colubris, by Mark Moschell, Jun 2019; Great-horned owl, Bubo virgianus, by Kevin Milazzo, Feb 2021}

Narrow tweezer-like beaks, used by gnatcatchers, warblers, and wrens, stab or seize small insects from branches. Wider and flatter tweezer-shaped beaks on purple martins and flycatchers can snatch an insect in flight. Long, slender beaks on hummingbirds are made for sucking nectar from the deep recesses of long, tubular flowers as well as catching tiny insects, such as fruit flies. Sharply pointed, hooked beaks are used by eagles, owls, hawks and shrikes to stab prey and hold on while pulling the meat apart into mouthful-sized chunks.

Many beaks serve more than one feeding function, as species change their diet from one type of food to another as seasons change. Tongues are an important addition to the mouth, manipulating food items for beaks to be more effective. Different sizes and colors of beaks convey information to other individuals about a birds sex and maturity level. This essential body part provides birds with many of the same capabilities as other animal species. Come to the Jurica-Suchy Nature Museum, or a nature center near you, to learn more about the many adaptations of birds.

^{Ruddy Duck, Oxyura jamaicensis, by Sergey Yeliseev, Nov 2013}

Venomous Snakes Of Illinois

There are 40 snake species native to Illinois, and they are found in all types of habitat from woodlands and prairies to wetlands and urban areas. Of these, four species are venomous. A venomous snake is one that uses a chemical toxin to kill its prey. This internally developed chemical is delivered through a pair of hollow fangs in the upper jaw of the mouth. When the snake opens its mouth, the fangs drop down and venom is injected into the prey as the snake bites. The snake will then release the prey, waiting for the venom to kill it before swallowing the prey whole. Juveniles will inject less venom, but with the same potency as adults.

^{Pit viper Fang and Jaw Structure drawn by M Moran at Encyclopedia Britannica}

Venomous snakes in Illinois are all pit vipers, a sub-family of the Viperidae family of snakes. The pit, a large opening between the eye and the nostril, just above the upper lip, can detect heat given off by warm-blooded prey species. Their elliptically-shaped eyes is another characteristic that helps to identify venomous snakes.

^{Close-up of elliptical eye on Copperhead by Mark Dumont, Jun 2011}

^{Close-up of pit above upper lip on pit vipers, by Scott Ballard, IDNR}

Illinois venomous snakes are non-aggressive in nature, but will bite if cornered, harassed, or stepped on. Bites are usually not fatal in humans, but they can be quite painful, often resulting in swelling and possible infection. Vomiting, nausea, and tissue or nerve damage may also result. Anyone that is bitten should seek immediate medical attention.

^{Eastern Copperhead, Agkistrodon contortrix, by Peter Paplanus, Aug 2018}

^{Eastern Copperhead close-up, Agkistrodon contortrix, by Peter Paplanus, Apr 2021}

The Eastern Copperhead, Agkistrodon contortrix, lives in the southern third of Illinois on wooded hillsides, river bluffs with sandstone or limestone outcroppings, and along forest edges. During the hot summer months, they may also feed on the abundant rodent populations in meadows or near abandoned buildings. The copperhead is about four feet in length and has a light brown back with one to two dozen reddish-brown colored hourglass-shaped markings along the back. The top of their head is a brighter red-brown.

^{Northern Cottonmouth, Agkistrodon piscivorus, by Virginia State Park Service, May 2016}

^{Northern Cottonmouth flashing white, Agkistrodon piscivorus, by Peter Paplanus, Aug 2022}

The Northern Cottonmouth, Agkistrodon piscivorus, resides in far southern parts of Illinois, living in swamps, sloughs, and oxbow lakes. At five feet in length, this heavy-bodied snake is a uniform charcoal or dark olive color, with dark crossbands and a tan to gray belly. When disturbed, its response is to face its attacker and open its mouth widely, displaying the bright white interior, earning the name of cottonmouth.

^{Timber rattlesnake close-up, Crotalus horridus, by Peter Paplanus, Apr 2023}

^{Timber rattlesnake, Crotalus horridus, by Peter Paplanus, Apr 2023}

Timber rattlesnakes, Crotalus horridus, live in both southern and northern areas along the Mississippi River and Illinois River valleys. Usually found in heavy timber with rock outcrops or bluffs, this snake, up to six feet long, is marked by two dozen black crossbars down a gray-green-yellow back. Its belly is light-colored with dark edges, and it shows a dark strip behind each eye. Timber rattlesnakes will hunt in any areas where there is a large rodent population. They are listed as threatened since we have seen sharp declines in the populations in recent years.

^{Massasauga Rattlesnake, Sistrurus catenatus, by Peter Paplanus, Apr 2021}

^{Massasauga Rattlesnake close-up, Sistrurus catenatus, by Peter Paplanus, Apr 2021}

The Massasauga Rattlesnake, Sistrurus catenatus, is found in small numbers scattered across the state, mainly in prairie wetlands and river floodplains. Listed as endangered in the United States, it has become quite rare in Illinois with only a couple sightings annually for the past several years. Massasaugas are about two feet in length, with a gray to light brown back and 30-40 dark, bow-tie shaped markings. Four to seven darker rings cover the tail. Their main prey is small rodents.

Venomous snakes have small ranges, staying close to home for hunting and mating. Their main predators include humans, birds of prey, and other snakes. Many have been killed by people with an unfounded fear of these creatures. Although they play a major role in controlling rodent populations, there has been little concern shown over loss of habitat due to draining of wetlands and other urban development. Plan a visit to the Jurica-Suchy Nature Museum or a nature center near you to learn more about these mysterious, yet wonderous 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).

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.}

Bear Bones

^{Grizzly Bear Ursus arctos, by Don Arnold, JSNM 2025}

As in many other natural history museums, the Jurica-Suchy Nature Museum displays mounts of animals or their parts including bones, skulls, teeth, pelts, claws, and feathers. Osteology is the study of bones in order to understand their structure and function, and how they relate to an animal’s lifestyle. At our museum we have several species of bears on display, plus bear skulls, bones, and claws for additional study.

^{Black Bear Ursus americanus, skull and dentition by Don Arnold, JSNM 2025}

Looking at a bear’s skull, we can see that they have up to twelve front teeth used for nipping and cutting. Their four long, sharp canine teeth are used to grab and hold their prey, and to tear apart the meat. There is a space between the front teeth and the flat molars in the back of the mouth, often found on herbivores, animals that eat vegetation. Bears are omnivores, including both meat/protein and vegetation in their diet, eating any small mammal up to the size of a deer fawn in addition to plants, seeds, and berries of all kinds.

^{Kodiak Bear Ursus arctos middendorffi, long & large nose by Don Arnold, JSNM 2025}

^{Polar Bear Ursus maritimus, skull and nasal opening by Don Arnold, JSNM 2025}

The long and large nose is another prominent part of a bear’s skull. A large nasal opening contains a complex system of bony plates intricately woven together. The plates create a much larger surface area than only the inside walls of the nasal opening, and are all covered with membranes capable of detecting scent. Bears have an excellent sense of smell, about seven times better than a bloodhound and more than 2,000 times better than a human. They can distinguish one or more scents from among dozens, detectable from as far away as two miles. Bears use their sense of smell to find food, mates, and family, and to identify potential threats.

^{Grizzly Bear Ursus arctos, small eyes & ears by Don Arnold, JSNM 2025}

^{Polar Bear Ursus maritimus, nose, ears, eyes by Don Arnold, JSNM 2025}

The ocular (eye) openings indicate that a bear’s eyes are located on either side of its nose, and face forward. This provides bears with binocular vision allowing them to see three-dimensional images and judge depth-of-field, the distance between a near object and a farther away object. Knowing how far away and how big another animal is compared to itself enhances its abilities to find and capture prey as well as avoid potential predators. Ear openings, at the lower back of the skull are difficult to find. The openings are tiny, and the auditory bone inside is small and flat. Bears have small eyes, with average eyesight, and small ears with slightly less than average hearing capabilities.

^{Polar Bear Ursus maritimus, sharp}
^{claws by Don Arnold, JSNM 2025}

^{Grizzly Bear Ursus arctos, claws for digging by Don Arnold, JSNM 2025}

^{Black Bear Ursus americanus, grasping claws by Don Arnold, JSNM 2025}

Their claws, another important part of a bear’s body, serve many functions to help them to survive in their environment. A polar bear’s claws are about five inches in length, thick, sharp, and slightly curved. They are used to gain traction on the ice when running or pulling themselves out of the water and onto an ice floe. A grizzly bear’s claws are about the same size, but stouter and not as sharp. They are used for pulling logs apart, digging dens, and scratching roots and invertebrates out of the ground. Black bears have the shortest and straightest claws, about two inches in length. They are sturdy claws, not as good for hunting and digging, but are excellent for climbing trees, an activity used by smaller bears that can pull their own weight upwards.

^{Black Bear Ursus americanus, tree climbing by Don Arnold, JSNM 2025}

Many other facts can be learned about the lifestyles of bears from around the world by studying bones, skulls, skeletons, paws, and whole specimens. Consider visiting us at the Jurica-Suchy Nature Museum to learn more by making a reservation at: JSNM Reservations (http) (enter hotlink)

Illinois Owls

Owls are found year-round in northern Illinois, and they come in several sizes and shapes and live in various habitats. Owls found near urban areas are often active only in the evening or at night, making them elusive to find and observe their behaviors. Native owl species have a highly varied diet, hunting almost every animal smaller than themselves from insects and crustaceans to small mammals, reptiles, and amphibians. Some of their unique characteristics and places to find them are highlighted below.

^{Barn Owl, Tyto alba pratincola, by DonArnold, JSNM Museum and Great Horned Owl, Bubo virginianus, by DonArnold, JSNM Museum}

Great Horned Owls, Bubo virginianus, live in every habitat across North America, Central America, and parts of South America. Standing two feet tall with mottled brown and gray feathers, they are well camouflaged during nighttime activities. Their ‘horns’ are actually feather tufts sticking out above their ears, which may enhance hearing and make them easy to identify. Look for them at dawn and dusk in tall trees standing on the edges of open spaces. The Barn Owl, Tyto alba, hides in tree hollows or dense vegetation during the day, coming out to hunt at night. They are a foot tall with a distinct white face and chest and pale brown and gray backs. A high energy lifestyle requires them to eat more than other animals their size. They are mostly found in open fields near wooded areas that provide diverse habitat for prey.

^{Barred Owl, Strix varia by DonArnold, JSNM Museum; Northern Saw-whet Owl, Aegolius acadicus by DonArnold, JSNM Museum; Short-eared Owl, Asio flammeus by DonArnold, JSNM Museum}

Three owls are daytime hunters, but not often found in urban areas. Barred Owls, Strix varia, have small territories, covering no more than a few square miles during their lifetime. They are brownish gray with dark stripes on their bellies. They hunt during both daytime and nighttime and have been known to eat carrion if it’s easily available. Look for them in wetlands with mature woodland cover nearby. Another daytime hunter, the Short-eared Owl, Asio flammeus, is an abundant species standing about a foot tall and known by its brown speckles covering a cream colored undercoat, with a barred tail and wings and a light belly. Their diet is similar to other owl species, but they may also hunt rabbit and weasel. Look for them flying low to the ground in open areas including grasslands, meadows, and wetlands. The Northern Saw-whet Owl, Aegolius acadicus, is only six inches tall, with a round, light colored face and belly streaked with brown, and a brown back with light spots. They are highly maneuverable and can easily hunt in small spaces. These owls have incredibly sharp talons and beaks, and they are able to take down prey larger then themselves. They favor dense, mature forests, especially those containing conifers.

^{Eastern Screech Owl, Megascops aslo, by DonArnold, JSNM Museum; Long-eared Owl, Asio otus, by DonArnold, JSNM Museum}

The next two species are smaller, nighttime hunters, often found in urban areas. The Eastern Screech Owl, Megascops aslo, stands eight inches tall and is all grey or slightly reddish-tinged. This owl species has also been observed feeding on fruits and berries. They are found in forests, wetlands, and urban neighborhoods with mature trees. The Long-eared Owl, Asio otus, one of the most abundant owl species world-wide, is a foot tall, with black and brown plumage. They hunt by stealth, waiting on a perch for prey to come close, then pouncing. Look for them in urban settings with large trees and in many state park areas.

Snowy Owl, Bubo scandiacus, by DonArnold, JSNM Museum

A winter only resident, the Snowy Owl, Bubo scandiacus, stands two feet tall with distinctive, almost pure white plumage. They are active both night and day, and can cover large distances in their daily hunts. A large, ferocious hunter, they can take down prey larger than themselves. They are found in a widely diverse set of habitats including open grassland, wetlands, shorelines, and several of our area’s larger airports.

We have many owls on display at the Jurica-Suchy Nature Museum. Come in and learn from our newest Illinois In Winter display or our owl and other raptor displays. We are closed for the holiday break, but consider visiting us as we reopen for the Spring semester in early January. Check out our schedule and make a reservation to come see us at https://ben.edu/campus-links/jurica-suchy-nature-museum/.

Illinois Owls

Owls are a type of raptor, a bird of prey with forward-looking eyes, large talons, and hooked beaks. Raptors are known for having the best vision of any animal, and they are skilled hunters found across all habitats. Other raptors include hawks, eagles, falcons, kites, and vultures. There are nineteen owl species native to North America, and eight of them are regularly found in Illinois.

^{Pictures clockwise above: Black Kite by Martine LIU, Getty Images; Golden Eagle by Timu Abasov, Getty Images; Red-tailed Hawk by BrianEKushner, Getty Images; Turkey Vulture by James Opiyo, Getty Images; Peregrine Falcon by Harry Collins, Getty Images Pro}

Owls have large eyes that look forward and provide a wide angle of view. Their binocular vision helps these birds easily spot prey and accurately judge distances when either stationary or in flight. An owl’s eyes cannot move within the eye socket, so the owl must move its entire head, which is capable of rotating 270 degrees to see completely around itself. Their vision is extremely sensitive to light, and they are capable of hunting when conditions are quite dark.

^{Barn Owl face by QuentinJLang, Getty Images}

^{Great-horned Owl looking back by Celine Bisson, Getty Images}

The feathers on their round faces help to direct sound into their ears, which are located on either side of their head. Their ears are small openings covered by feathers that can enhance and separate sound waves, working like binocular vision, allowing the bird to identify how far and in which direction a sound originates. Their enhanced ability to detect movement around themselves, coupled with excellent vision, makes these birds of prey one of the top hunters in their environment.

^{Owl beak closeup by GrahamH, Pixabay; Snowy Owl talons by WWing, Getty Images; Black fur in owl pellet by Justin Smith, Getty Images}

Sharp beaks and talons are used to capture and hold prey, and to easily tear apart meat. All raptors have eight toes ending in a talon, or sharp claw, made of keratin. Owl talons are long and curved and are used to easily grasp a branch or a prey animal. Their beaks are made of bone covered with keratin, with very sharp edges. They have no teeth to chew food, and they eat their prey whole or in large chunks. Whatever is not digestible, including bones, fur, and feathers, is compressed into a wad in the owl’s mouth and spit back out as a pellet. An Investigation of owl pellet contents can reveal the prey the owl is currently eating.

Fringed ends of owl flight feathers by ElvisCZ, Pixabay

Owls have fringed outer edges to their flight feathers that deaden almost all sound made while flying, making it difficult for prey to detect an owl coming for them. An owl’s large, rounded wings and short tail provide great maneuverability while flying. Their excellent vision, hearing, and flight maneuverability allows them to hunt at night in areas with numerous obstacles including woodland and urban areas.

In the next blog, I will take a closer look at the owls in Illinois. At the Jurica-Suchy Nature Museum, we have several displays that highlight the various characteristics of owls and other raptors. We are closing for the holiday break, but consider visiting us as we reopen for the Spring semester in early January. Check out our schedule and make a reservation to come see us at https://ben.edu/campus-links/jurica-suchy-nature-museum/.

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.

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

Dinosaurs At The Museum

Dinosaurs roamed North America millions of years ago, and while they are no longer part of the wildlife, we are able to see, study, and learn from them at the Jurica-Suchy Nature Museum (JSNM). Bones, skulls, teeth, and stomach contents unearthed at various sites are housed in numerous worldwide institutions.

^{Triceratops at JSNM by DonArnold, Oct 2023}

Triceratops was a common visitor to areas of western North America in the late Cretaceous period, from 68 to 66 million years ago. The name is Greek meaning “three-horned face.” The animal’s distinctive skull has two long horns located above the brow line of each eye, and one shorter horn off the tip of the nose. The brow horns, situated high on the head, may have exceeded three feet in length on the largest animals. A frill, or bony structure surrounding the back of the head, makes the head seem larger than the skull alone. In Triceratops, the frill could exceed seven feet from side to side.

Triceratops were large animals standing 10 feet tall with a length, from nose to tail, of about 30 feet. Their teeth were long and intimidating, but these animals were actually vegetarians. The teeth were used to shear through fibrous plant material that was difficult to cut and chew. The horns were very strong. They were used for defense against predators and when dueling for territory with other Triceratops individuals.

^{Tyrannosaurus rex half skull at JSNM by DonArnold, Oct 2023}

Tyrannosaurus rex, Greek for “king of the tyrant lizards,” is another species from the western United States. These animals moved swiftly on two huge rear legs. The body weight was balanced over these legs by a long, heavy tail and a massive skull. A full grown adult was estimated to be 13 feet tall, 41 feet in length, and weighed about 10 tons.

The skull cast at the Jurica-Suchy Nature Museum has several openings, thought to reduce the mass of the bony structure. It is very wide at the back, tapering to a narrow nose in front. The eyes are situated to provide excellent binocular vision, allowing the animal to accurately judge size and distance while running at a good pace. This was helpful for trapping prey and avoiding attackers.

^{Artistic rendering of Edmontosaurus by DariuszSankowski, Pixabay}

^{Edmontosaurus femur at JSNM by DonArnold, Oct 2023}

Several other fossils found in North America are on display at the museum. One is a femur from an Edmontosaurus, a genus of hadrosaurid or duck-billed dinosaur that lived alongside Triceratops in the western U.S. This dinosaur was a plant eater that could move on either two feet or all four feet. It is one of the best-studied species in the world due to the large numbers of bones that have been found. The skull held several hundred teeth, although only a few were in use at any given time. The rest were ready replacements for teeth that broke or wore down from the abrasive plant material in its diet.

^{images clockwise: Diplomystus analis; Diplomystus dentatus; Icthyosaur Stenopterygius Quadriscisius; Knightia alta; Mioplosus; Notogonius Oscuius; Perca obtusa; Phareodus testis; Priscacara liops; Pterosaur Phyllurus Ramphrhynicus; all images by DonArnold, Oct 2023, JSNM}

Other fossils available to view at the Jurica-Suchy Nature Museum include several fish species from the Cretaceous period that can be seen in the gallery above. Come on out to the museum to see these fascinating specimens and learn more, or take a trip to visit a natural history museum near you.

Oak-Hickory Forest

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

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

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

^{Arisaema triphyllum berries by ES3N, Getty Images}

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

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

^{Oak woodland by fotoVoyager, Getty Images Signature}

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

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

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

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

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

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

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

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

The Ocean Deep

Seventy percent of the Earth’s surface is under the ocean, and only a small portion is in shallow water along continental shelf areas. The ocean is divided into five zones; the sunlight zone, above 650 feet; the twilight zone, extending to 3300 feet; the midnight zone, down to 13,000 feet; the abyssal zone, down to 21,300 feet; and the hadal zone, extending to the bottom of the ocean. Below 3,000 feet, no light penetrates from the surface; the water temperatures are freezing; and oxygen levels are very low. The pressure exerted on any surface at sea level is 14.7 pounds per square inch (psi), and humans can withstand three to four times this amount, or 45 psi to 60 psi. At 3,000 feet deep, the pressure is 1,345 psi.

^{Delta submersible by Robert Schwemmer, CINMS, NOAA, Oct 2010}

Pressure keeps sea water from becoming solid ice, even when it is at freezing temperatures. It also makes exploring the ocean difficult, requiring special submersible vehicles. Everything moves more slowly under pressure, and a submersible can take an explorer deep into the ocean given enough time and oxygen. Deep sea creatures can survive because the structure of their bodies is lean and contain no air spaces. Let’s take a look at a few of the wondrous creatures that live in these habitats.

^{Humpback anglerfish by August Brauer in Public Domain}

In the darkness of deep areas, many species find food and mates by touch. Others may use bioluminescent communication – the ability to create light from a chemical reaction between luciferin and oxygen within an organism’s body. Lights show up as spots of various colors on different parts of the body and may be used for attracting a mate, confusing a predator, or attracting prey. Lanternfish have several spots located on their heads, undersides, and tails. Female anglerfish and dragonfish have a shaft that protrudes from their head out in front of their mouths with a glowing tip attracting prey within striking distance. Gulper eel use the lighted tip of their tail as a lure to attract a meal.

^{Tripod fish by NOAA Okeanos Explorer Program, Public domain, 2010}

^{Fangtooth fish by Sandra Raredon-Smithsonian Institution, Public domain}

Tripod fish have two pelvic fins and a tail fin that are elongated and can be filled with fluid to stiffen them, allowing the fish to stand on the ocean bottom while conserving energy. Two long, wavy pectoral fins act as arms to detect prey floating or swimming by and push the prey toward their mouths. Fangtooth fish is another species that can detect vibration and nearby movement. This species is only six inches in length, but have the largest teeth in proportion to their body size of any fish in the ocean. The long lower fangs fit into pouches in the roof of their mouths so their teeth do not pierce their brain cavity.

^{Dragonfish teeth array by UC San Diego Jacobs School of Engineering, May 2019}

The dragonfish, another small fish about six inches long, has a frightening array of teeth located on its jaws and tongue. Their teeth are transparent and their bodies are black, making them impossible to see even in depths where there may be some light. The jaws are loosely hinged, allowing the fish to open its mouth wider than normally hinged jaws would allow. Prey swimming nearby may not notice the wide opening, nor be able to detect the transparent teeth, making the dragonfish a top predator of invertebrates, squid, and shrimp. In addition, when biting, they inject a highly toxic poison to paralyze and kill their prey. This toxin can be dangerous to humans getting bitten or attempting to eat this species.

^{Giant spider crab by Michael Coghlan, Jan 2014; Gulper eel by Claf Hong, Mar 2005; Lanternfish, Myctophum punctatum1 by Emma Kissling}

Some fish practice diel vertical migration, a pattern of movement where a species feeds near the surface at night and moves back into deeper waters to rest during the day. Lanternfish come up to feed on zooplankton and fangtooth fish feed on squid in shallow waters. Some species, including anglerfish and gulper eels, have elastic-like skin for their mouths and stomachs. Mouths can be opened extremely wide to swallow prey larger then themselves. The food is contained in a similarly elastic stomach which shrinks slowly as digestion progresses. Several different species of spider crabs roam the ocean depths scavenging for meat or plant material that falls to the bottom.

Deep-sea animals are seldom seen, but are not immune from climate change and human impacts. Scientists continue to study changes in deep-sea food webs caused by overfishing, ocean acidification, and expanding low-oxygen zones. Learn more about the habitat and species of these areas at the Jurica-Suchy Nature Museum at Benedictine University or your local nature museum or aquarium.

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.

Forest Litter, Hand Lens Views

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

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

Springtails, aka Snow Fleas, by mwms1916, Mar 2015

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

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

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

Pseudoscorpion by Philippe Garcelon, Mar 2021

Pseudoscorpion by Philippe Garcelon, Oct 2018

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

Eastern Bess beetle larva, by Katja Schultz, Jul 2014

Ground beetles by Bernard DuPont, Feb 2006

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

Ants in bark by Michael Jefferies, Mar 2010

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

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