movement – 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.

Red Panda

The red panda, Ailurus fulgens, a small mammal closely related to weasels and raccoons, is found in the Himalayan and Tibetan mountain ranges of Nepal, Bhutan, and southern China. There are two subspecies, the Himalayan red panda and the Chinese red panda, differentiated by slight skull and color variations. They were isolated almost 200,000 years ago by glaciation in the Brahmaputra River Valley.

Red pandas live in steeply sloped, heavily forested areas where bamboo grows in dense thickets and there is easy access to water. Their habitat ranges in altitude from 6,500 feet to over 14,000 feet, in a temperate area with average temperatures in the upper sixties (Fahrenheit). These mountain ranges contain many protected pockets of forest, interconnected with wildlife corridors through unprotected country. Some areas overlap habitat where the Giant Panda lives, and the two species must share the bamboo in these locations.

_{Red panda, Ailurus fulgens, by Pixabay 27707, Sep 2015}

_{Red panda, Ailurus fulgrens, climbing at Taronga Zoo, by Charles Wong}

The red panda has a round head with a short snout and white fringed, triangular ears. Adults are 24″ long and weigh about 15 pounds. Their fur is dense, reddish-brown and covered with dark guard hairs. A black belly and legs, with a white muzzle and alternating red and buff rings along an 18″ tail, ensures that the red panda is well camouflaged in a forested area covered in red moss and white lichen. They have five curved claws on each foot that can be partially retracted in addition to flexible joints in their pelvis and hind limbs and an elongated wrist bone ending in a false thumb. All of these adaptations allow for a great range of motion when climbing and moving about the forest.

_{Red panda, Ailurus fulgens, mom and newborn by Rainer Halama, Jul 2013}

Red panda, Ailurus fulgens, twittering

The red panda lives in solitude, except during mating season in late winter when they cautiously seek out mates, resting and feeding near one another for short periods. Mating occurs on the ground, and gestation lasts 13 weeks, but can be prolonged up to 24 weeks at the discretion of the mother. The female selects a den site, building a nest of sticks, leaves, grass, and moss. Litters are between 1 and 4 babies weighing only 3 to 4 ounces at birth. Babies are born covered in fur for warmth, but blind for their first 18 days. They depend on their mother for everything for three to five months, and will not leave home until a year has passed.

_{Red panda, Ailurus fulgrens, sunbathing by Su-May, Sep 2011}

_{Red panda, Ailurus fulgrens, Conservation of energy by Tina R Tiller}

Red pandas move easily through the trees as well as over open ground. Trees next to bamboo stands provide places to sit higher up and eat, but the forest also provides shelter, an escape route from potential predators, and branches to sunbathe on in colder weather. If temperatures become too bitter, red pandas can lower their metabolic rates, curl into a tight ball, and sleep for a few hours to conserve warmth and energy. Bamboo makes up a large part of their diet, but it is supplemented with fruits, flowers, eggs, small mammals and birds. They prefer to eat early in the morning and late in the afternoon, while intermittently sleeping during the remaining hours.

_{Chinese red panda, Ailurus fulgens, named Kinta at Nogeyama Zoo, by Toshihiro Gamo}

Red pandas are on the endangered species list with decreasing populations near 10,000 in the wild. Their primary predators include leopards and jackals, which they can escape from using their climbing skills and agility through rocky and forested areas. But their main threat comes from poachers who prize their fur and bushy tails for the hat making industry and habitat destruction and land development that is steadily cutting large forests into small, isolated acreages. Red pandas have been well studied and are a favorite species at many zoos. Consider getting out this year to see them and learn more at a zoo near you.

Tracks In The Snow, pt.2

In the last blog we explored many of the characteristics of tracking. In this blog, we’ll explore tracks, eating patterns, and scat from animals that are active in northern Illinois throughout our winters. Many of these species live elsewhere, as well, and the information here can be applied to other species with the same characteristics as those in Illinois.

White-tailed deer, Odocoileus virginianus, domesticated horse, and bison, Bison bison, can all be found and observed in many urban and agricultural areas of northern Illinois. These hoofed mammals all walk on their toes, making a deep print of two toenails split down the center. The pointed end faces the direction the animal was traveling.

^{White-tailed deer, Odocoileus virginianus, by mirceax, Getty Images}

^{Deer tracks by florathexplora, Mar 2008}

^{Bison, Bison bison, grazing by belfasteileen, Getty Images}

Hoofed species in this area are all browsers and grazers. Browsers feed on leaves, fruit, and soft shoots of woody plants. One browser in this area, the white-tailed deer, leaves a distinct bite pattern exhibiting a ragged tear from the lower teeth and a clean cut from the upper teeth. Deer also use their lower teeth to scrape away soft bark from trees such as cherry, apple, willow, and sumac. Grazers feed on grass and lower-growing vegetation. These species include horses and bison which bite grass off close to the ground.

^{Rabbit tracks by Lorianne DiSabato, Jan 2025}

^{Squirrel tracks in snow by Tracy Rolling, Feb 2010}

Rabbits, squirrels, and chipmunks all move with a hopping motion. The smaller front feet land first and the larger hind feet land immediately in front of the front feet. Squirrels and chipmunks have five toes on the hind feet and four toes on their front feet. Rabbits have furred feet, effectively hiding the distinct toes, and their tracks appear as a large oblong hind foot in front of a much shorter front foot. The spacing of the tracks indicates of how fast the animal was moving.

Eastern cottontail rabbits, Sylvilagus floridanus, have teeth on both the upper and lower jaw, leaving a clean, forty-five degree angle cut a few inches off the ground. They prefer sumac, maple, apple and oak. Other signs that may be present where rabbits have eaten are scat piles. Their scat is small ovals that come out one at a time, so a pile of scat indicates that the rabbit stayed in that one spot for an extended period of time. Squirrels and chipmunks both have continuously growing incisors that leave distinct, small parallel grooves on the ends of woody shoots they have chewed.

^{Perching bird tracks in snow by Jim Forest, Feb 2017}

^{Webbed trails, Raritan River Bank by joiseyshowaa, Jan 2009}

Woodpecker tracks show two toes pointing in each direction. Perching birds have one toe pointing backwards and three toes pointing forwards. Larger birds of prey such as hawks and owls may have tracks that are blurred indicating feathers covering their toes. Waterfowl, including ducks and geese, will make flattened tracks showing webbing between their toes.

^{Owl wing prints and attack point by Chris Fournier, Dec 2013}

Many larger hawks and owls in our area hunt by soaring on wind drafts while scanning the ground below for prey. When a mouse or other small animal is found, the predator will dive from overhead to snatch up the prey or pin it to the ground before killing it, then possibly taking the prey to another location to eat. Wing marks and depressions in snowy areas are clear indications of an attack.

^{Raccoon tracks by August Ride, Jan 2018}

^{Opossum track by Phil Myers, Univ of Mich, Ann-Arbor, Feb 2009}

The North American raccoon, Procyon lotor, and Virginia opossum, Didelphis virginiana, have alternating prints. Raccoons leave a round print with five long toes that distinctly resembles a human footprint. Opossums also have five toes, but the outer one is opposable, like our thumb, and leaves a distinctive print with four toes pointing forward and one pointing to one side. You may also observe a wavy line between the opossum tracks as it drags its tail along.

Canines and felines have padded feet. Clues to the specie’s identity come from observations of the general shape of the imprint, how many toes there are, if there are claw marks at the ends of the toes, and the general pattern left by the trail of prints. Canines including dog, red fox, Vulpes vulpes, and coyote, Canis latrans, walk on their four front toes. Each footprint will show a back pad, a small pad behind each toe, and a claw mark in front of each toe. The overall imprint will be longer than it is wide. Red fox trails exhibit direct registration, with the hind foot stepping directly into the track left by the front foot but other canine species show indirect registration with front and hind tracks slightly separated.

^{Coyote tracks in snow by David Merwin, Mar 2007}

^{Bobcat track by Frank D Lospalluto, Feb 2016}

Felines include domesticated cats and bobcats, Lynx rufus. These animals have similar prints from walking on their four front toes, but a feline track shows the back pad and four toe pads in a circular impression, and no claw marks because they withdraw their claws when walking.

When observing tracks, keep in mind these points: whether hind feet and front feet are different, how many toes are showing, are there claw marks, is there webbing, feathers, or fur between toes, which foot is in front, and the shape of the print. Consider a tracking field guide or a visit to the Jurica-Suchy Nature Museum or a natural history museum near you for more information.

Tracks In The Snow

As a naturalist and observer, a person can spend a lot of time and effort trying to get close to wild animals, while most animals are trying hard to remain hidden from our view. With the arrival of winter, observing animals directly becomes even more difficult. Many stay hidden in nests and burrows, out of the wind and weather. Others stay out of sight during the day when predators are able to more easily spot prey against a snowy, white backdrop, and only come out during the night to find food.

^{Deer hiding from photographer in winter woodland, by Nicolo Bonazzi, 2016}

^{Eastern chipmunk makes an easy target for a sharp eyed predator, by Tom Murray, Feb 2021}

When an animal does move around, it will often leave tracks in the snow and mud, providing clues for us to study. Who made the track? Where did the animal come from or go to? Were they walking, searching for food, exploring shelter, or running, possibly from a predator? Observing individual prints or groups of prints taken as an overall pattern in the habitats where they were made can reveal interesting facts about each one.

Field guides are an excellent source of information to supplement observations, and you should get to know the following six terms. A track is an imprint of one foot whereas a trail is many tracks strung out in a pattern. Direct registration, made by a fox, occurs when only one imprint is visible because the animal places its hind feet directly into the track left by the fore feet. Indirect registration, made by a domesticated dog, is when the hind footprint appears just outside the fore footprint. An alternating pattern made by a raccoon shows the left hind footprint next to the right front footprint and vice versa. A hopping or bounding pattern from a rabbit shows front feet and hind feet together, with the hind feet appearing in front of the set of four prints.

^{Clockwise from upper left: Bird track by Sharon James, Jan 2013; A trail of tracks by Denise Kitagawa, Feb 2018; Direct registration: Red fox tracks, by Kent Kanouse, Dec 2013; Indirect registration: Dog tracks in snow, by Jeanne Fox, Dec 2007; Alternating pattern: Raccoon prints in the snow, by Andrew, Mar 2017; Hopping pattern: Rabbit tracks in snow, by Ann, May 2019}

There are four general types of tracks made from feet. Birds leave small, hopping, four-toed prints with either one toe pointing backwards and three toes pointing forwards, or in the case of woodpeckers, two toes pointing in each direction. Hoofed animals including deer, horses, and sheep have larger, two-toed prints. Animals with padded feet including dogs and cats leave a print showing four or five toes in front of a large back pad. A non-descript category includes all of the tracks for animals that do not have feet or are not using their feet when the track is made. Naturalists may also observe imprints in the snow or mud from other body parts. These may include feather markings from tails or wings, wavy lines from dragging tails, or packed down areas from dragging bellies.

^{Bird tracks in snow by zenjazzygeek, Mar 2016}

^{Hoofed animal track by florathexplora, May 2008}

^{Padded tracks from bobcat by Placeuvm, Jun 2007}

^{Wing swoop in snow, by Drew Brayshaw, May 2008}

In addition to tracks, other evidence provides information on what the particular animal was doing at that spot. Scat is often distinctive for each animal, and the contents can show what the animal has been eating. This will give us further clues to provide species identification, the size of the animal, and where it might be finding its food. Toothmarks or claw marks on nearby vegetation can help to indicate a specific species. Be sure to observe individual footprints, the overall trail of imprints, and the type of terrain and vegetation in the area. Also note how wet or dry the snow or mud is, as this may make prints easier or harder to distinguish details.

Tracking can be a rewarding activity, providing many clues to help identify animals active in your area and what they are doing during this time of the year. Next time, we will take a more in-depth look at some of the animals in the winter habitats of northern Illinois.

Seaside

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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/.

At The Waterhole

Last week, we discovered adaptations that allow elephants to deal with gravity and heat. Asian elephants live mostly in tropical forests that are warm from plenty of sunlight, although very little light reaches through the canopy to the forest floor. Rainfall may be intermittent, and shade-tolerant vegetation changes with a lack or an abundance of water. African savannas have lots of grasslands with a few trees and shrubs. They have distinct wet and dry periods, but grasses grow deep root systems that sustain them throughout the year. African woodlands are more open than Asian forests allowing a variety of trees and shrubs that grow well in full sunlight.

Elephants live in large groups, called herds, led by the strongest adult female. The herd members include all the females plus any males who not yet teenagers. The matriarch knows where to find food and water. She is aggressive when it comes to protecting the rest of the herd and is always the first to confront any threat. Males grow into bulls and will start to fight other males in their teen years. Once this aggression starts, the matriarch will kick the young bull out of the family. Bulls travel alone or together with other bulls, but it is a dangerous time for them because they do not have the support and knowledge of the matriarch for finding food and water.

_{^{The Herd by WLDavies, Getty Images Signature}}

Elephants are old enough to mate in their mid-teens. Pregnancy lasts 18-22 months, and each cow has a baby once every five years until they are in their forties. The herd is very social and several females take care of each calf. Water holes are places where the herd engages in many social activities. Elephants use water to drink, to swim and play in, and to bathe. However, bathing for an elephant means getting dirty, not clean. Elephants stir up the edges of a water hole to create mud to wallow in. Or they will cover themselves with water followed by dirt sprayed on their bodies with their trunks. Dried mud provides cooling from the sun and keeps biting insects away from tender skin. Elephants love water and bathe often, helping to keep skin moisturized.

Lovely mud by bucky_za, Getty Images Signature

Food eaten daily includes about 300 pounds of grass, tree bark, fruit, and other green vegetation. Elephants also need salt to supplement their diet. Their tongues are too short to lick anything not in their mouth, so they use their tusks to dig furrows in the ground and pile up soil and stones. Large stones can be placed into their mouth to lick salt from, and small stones are ground up by their huge molars. Food eaten daily includes about 300 pounds of grass, tree bark, fruit, and other green vegetation.

African elephants are larger than Asian elephants and males are larger than females in all species. Asian elephants average life span is about 80 years in the wild, while African elephants live only 60 years. They are excellent swimmers, often submerging their whole body underwater except for their trunks, which are used as snorkels to breathe. On land, they are slow moving, but can run short distances at better than 20 mph. They use many vocalizations to communicate such as grunts, rumbles, trumpets, screams, and purrs, and they can use their trunks to modulate sounds.

A thousand years ago, ivory was a hot commodity, and hunters exterminated elephants in North Africa. In the last century, after remaining populations were severely depleted by the late 1800s, many countries banned the trade of ivory. Elephants are recovering today, but poaching continues to be a serious threat. As more humans have moved into their native ranges, existing populations have to live in smaller areas. At their rate of food consumption, vegetation does not have enough time to grow back, and herds today are experiencing food shortages. Several conservation organizations are working to provide land for the establishment of wider ranges, care for orphaned elephants, and combat poaching.

You can see and learn more about these wondrous animals at your local zoo or natural history museum.

^{Clockwise above: African bush elephants by designerpoint, Pixabay; Masai Mara elephants by tankbmb, Getty Images; African elephant by Donvanstaden, Getty Images; Friends by cocoparisienne, Pixabay; Asian elephant by miharing, Getty Images}

Boreal Forest in Winter

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

^{Boreal Forest panorama by Mliberra, getty Images}

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

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

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

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

^{Spruce grouse by Impr2003, Getty Images}

^{Willow ptarmigan by Alex Berger, Mar 2022}

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

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

^{Canada lynx by Carol Gray, Getty Images}

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

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

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

Bird Migration

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

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

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

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

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

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

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

Junco, Junco hyemalis, by Colin Durfee, Mar 2020

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

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

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

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

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