Woodchucks, also called groundhogs, are large members of the squirrel family that can weigh up to 14 pounds! They’ve put on considerable weight all fall by eating vegetation like grasses, flowers, beans, and peas, and sometimes even climbing trees in search of sweet apples. Right now, these furry creatures are hibernating in underground burrows.

At the moment, woodchucks have slowed their breathing to one breath per minute and their heartbeat to four beats per minute! Their body temperatures have also dropped dramatically, from 98 degrees to 38 degrees Fahrenheit.

While it’s true that male groundhogs will briefly awaken and emerge this month, they aren’t actually looking for their shadows-they’re searching for a mate! Male groundhogs emerge in early February, check out the burrows of several nearby females, and stay the night with each before returning home. No mating occurs, and the male will go back to sleep for about another month before revisiting the females again…this time to breed.

Did you know? A woodchuck’s burrow can be up to 5 feet deep and 30 feet long! In addition to a grass-lined nest chamber, a burrow usually has a main entrance and several escape openings. Abandoned woodchuck burrows are used re-used by many creatures, like the red fox, raccoon, cottontail, skunk, opossum, and even snakes.

The largest owl to breed in Wisconsin will start mating in late January or early February. Like other birds, the great horned owl sings love songs to attract a mate. If you’re lucky, you may have heard their deep “Who’s Awake? Me Too!” call echoing in the woods. The males (who are the smaller of the two sexes) have a deeper voice than the females.

When it comes time to lay eggs, this particular owl will use the abandoned nests of other birds (usually a hawk or crow). The great horned owl will lay about 2-3 eggs in this nest, which both the male and female will sit on until they hatch. This usually takes about 4 weeks. Great horned owls are super parents who will protect and guard their young until they leave the nest at 1-2 months of age. If the nestlings are very lucky, they may live to be 13 years old.

Did you know? Great horned owls are one of the few creatures to regularly hunt and eat skunks. The smell doesn’t bother them because owls have a very poor sense of smell. These birds have also been known to eat other owls!

Insects have a variety of ways in which they deal with winter, not all of which include personal survival.

Eggs: Adult crickets, grasshoppers, and praying mantises die before winter, leaving behind their eggs to hatch in spring and populate the next generation.

Larvae: Some fireflies and other species of beetles spend the winter as small, soft grubs within the ground. A few moth species ride out winter in their caterpillar stages. A great example is the Isabella tiger moth (or woolly bear) caterpillar. These familiar brown and black larvae overwinter beneath bark, rocks, and logs.

Pupae: Some moths and butterflies wait for spring while in a cocoon or chrysalis attached to a tree trunk or under leaves. Luna and cecropia moths use this strategy.

Adults: Ladybugs are lucky enough to overwinter as adults. They cluster together in protected areas and remain inactive there until spring. Honeybees also huddle together, but within a hive, fanning their wings to release heat for themselves and their queen. Many adult beetles and ants survive by digging into the soil below the freeze line. They’ll spend the winter in the warmer temperatures there. Earthworms do the same, twining together in balls within the dirt.

Did you know? Wisconsin has one butterfly that overwinters as an adult…the mourning cloak.

As you walk through the winter woods, take a moment to think of the tiny wildlife that are traveling below you. Beneath the snow, small creatures like voles and mice are moving about unseen. There, they take advantage of warmer temperatures and an amazing transportation system. Fallen snow acts like a protective blanket, keeping temperatures below it constant even as the temperatures above vary. Heat from the warmer ground then melts a small space between it and the snow pack. This space is perfect for small mammals to create extensive tunnels in, allowing them to move and feed away from the watchful eyes of predators. Life isn’t perfect for them though; foxes, coyotes, weasels, and owls are on to this survival strategy. Their extraordinary sense of smell and hearing allows them to dive into the snow after a tasty morsel.

The next time you travel the trails of CWES, keep your eyes open for signs of hidden walkways. Look for raised lines of snow crisscrossing the trails. These subnivean (in or under the snow) tunnels are especially obvious on a day when the snow melts a bit. You may also see tiny openings as thick as a finger, these are air shafts that provide fresh oxygen to the tunnels below.

Did you know? Some birds, like ruffed grouse, take advantage of subnivean temperatures by tunneling beneath the snow to sleep at night.

This familiar bird will soon be singing and advertising its territory. Cardinals have bright, whistled songs that sound a bit like “Cheer, cheer, cheer, what, what, what, what.” Males often sing from the tops of trees, and after they have set up their territories, females may sing duets with them.

Male cardinals fiercely defend their territories from rival males. They have even been known to fight with their own reflections in windows! When selecting a mate it appears that looks do matter…at least to female cardinals. In these birds, the brighter the male, the better the mate. Scientists have noticed that bright red males hold better territories, eat more, and have better reproductive success than duller males.

Did you know? In the 1800’s, cardinals were prized as cagebirds, and thousands were trapped and sold until the Migratory Bird Act was passed in the early 1900’s.

On mild winter days, you may glimpse a few insects or spiders emerging from the leaf litter and traveling above the snow. If you are very lucky you may even notice an entire horde of small creatures. If they look like pepper sprinkled across the snow, you’ve probably stumbled upon snow fleas!

Snow fleas are not really fleas at all, but a type of arthropod called a springtail. At 1/8 of an inch long, snow fleas are just slightly larger than a pinhead. On warm winter days they emerge from beneath the snow, where they have been inactive, and feed on decaying matter above.

Did you know? Springtails get their name from a spring-like tail that is held under their body by two tiny hooks. When the hooks are released, the creature goes springing away. Sadly, the snow fleas cannot control where they spring to.

This long-bodied creature is the most widely spread mustelid (a family of mammals that includes badgers, otters, weasels, and their relatives) in North America. Their amazing hearing and smell make them successful hunters of mice, voles, rabbits, birds, and shrews. If this weasel kills more than it can eat, it will often cache the food for later.

This small carnivore is a clever camouflage artist. In summer, it is cinnamon brown with a white belly. In winter, its coat is gleaming white with a bit of black on the tip of the tail. The weasel’s color change is actually genetic. In southern climates where turning white would not be beneficial, it doesn’t change color. In fact, if you transported a southern-born weasel to Wisconsin, its coat would remain brown year-round. If you moved a Wisconsin weasel to a southern climate, it would still turn white during the winter season.

Did you know? Long-tailed weasels live in the abandoned burrows of other small mammals, and build themselves cozy nests there…made mostly of the fur of their prey!

Chances are you’ve seen a medium-sized, black bird at CWES, but was it an American crow or a common raven? Though you are much more likely to spot a crow than a raven in this area, both species nest in Portage County. Here are some tips for telling the difference between the two:

Call: This can be quite helpful. Crows have a raspy “caw,” while ravens give a deep, croaky “gronk, gronk.”

Number: If you see a large group of medium-sized, black birds, they are likely crows. Ravens are more solitary birds and typically are seen only one or two at a time.

Size: Ravens are slightly larger than crows and have larger, more curved beaks.

Throat Feathers: When perched, a raven’s throat feathers look much more shaggy and ruffled than a crow’s.

Tail: When in flight, a raven’s tail looks wedge-shaped while a crow’s appears more rounded and fan-shaped.

Cool Crow Facts: Crow families can be as large as 15 and include young from five previous years. These birds often help their parents raise their new young. In winter, crows roost overnight in groups that can be as large as thousands of birds or more.

Lichens are found on rocks and trees and often look like peeling paint. When you touch one it often feels dry and flakey. Lichens are an amazing symbiotic (good for both parties) relationship between a fungus and an alga. Fungi include mushrooms, molds, mildews, and rusts. Algae are the tiny, aquatic plants that we see in Minister Lake and can be single or multi-cellular. An alga intertwined with a fungus creates a lichen. The fungus makes up about 60% of the lichen and gives structure and protection to the alga. In turn, the alga photosynthesizes and gives food to the fungus. Lichens grow when they are moist and soak up early morning dew.

How does new lichen form?

There are several ways that a new lichen can be created. If a piece of lichen breaks off and lands in a moist spot, it can begin to grow. Lichens can also send out small packages of algae cells and fungi threads, which can grow into new lichens. The last way is for the fungal part of a lichen to send out tiny spores, which can create a new lichen if they land on an alga.

Did you know? Lichens are very important in creating new habitats, because they can slowly break rock into soil. Lichens are also good for padding bird nests and as food for squirrels, chipmunks, and deer. Lichens are sensitive to air quality and very few can survive in cities.

Learn more: http://ocid.nacse.org/lichenland/html/meeting.html

Right now, hidden beneath layers of bark, are the larvae of an extraordinary bunch of beetles. These minute insects are called engraver beetles, and you’ve probably seen their work on dead and dying trees at CWES. They carve complex patterns beneath bark as they eat and breed. Most of these wood-consuming beetles are quite small at about 1/8 of an inch long.

In spring, the hidden larvae will pupate, become adults, eat their way out of the bark, and then fly to a new tree. There, either the male or female (depending upon the species of beetle) will carve out a tiny chamber beneath the bark and mate with another beetle. Then, the female beetle will carve out tiny channels around the chamber to lay each of her eggs in. When the larvae emerge from their eggs, they feed on wood and widen their tunnels. They then pupate, became adults, and start the whole cycle over again. Several generations of engraver beetles can be produced over the course of one summer. The next time you see a dead tree or a fallen log, take a closer look and try to spot the trails of these unique creatures.

Have you ever seen a rectangular hole drilled deep into a tree? If so, you may have witnessed the handiwork of the pileated woodpecker. At 16-19 inches long, this impressive bird is the largest woodpecker in Wisconsin. You can tell males and females apart by the color of their “mustache.” The male has a red “mustache” at the corners of its beak while the female has a black one. Males also have more red on their foreheads. These birds don’t migrate, and a pair will stay together in their territory year-round.

After they’ve hammered a hole, pileated woodpeckers will use their long tongues (full of sticky saliva and a barbed tip) to catch carpenter ants and wood-boring beetle larvae. They will also munch on nuts and berries.

Did you know? These large birds are an important species because they create cavities in trees that may be used as homes for many other birds and mammals.

Hear this bird’s “kuk kuk kuk” call

Hear it drumming

Learn more: Cornell Lab of Ornithology

Keep an ear out for the barred owl at this time of year. Their monkey-like call of “Who cooks for you? Who cooks for you allll?” will be echoing through the woods soon as they establish territories and begin to breed. Like the great horned owl, barred owl pairs will perform duets while courting, with the male’s voice being lower. These pairs typically mate for life.

The barred owl prefers to make its nest in abandoned tree cavities. It will lay 2-3 white eggs there, which the female will incubate while the male brings her food. In about a month the eggs will hatch. If they make it to adult size, the birds will weigh about a pound and may live over 10 years. In order to survive, these owls will need to successfully hunt small mammals, rabbits, birds, amphibians, reptiles, and invertebrates. They will also need to avoid predators such as the great horned owl.

Did you know? Scientists estimate that an owl’s eyesight is about 100 better than ours in low light, and that their hearing about 10 times better!

Learn more: Cornell Lab of Ornithology

Let’s take a second to highlight a tiny, but unique creature sleeping beneath the snow and earth this season. At this moment, the meadow jumping mouse, a true hibernator, is nestled snuggly underground in a nest of grasses and leaves. While hibernating, it has a body temperature of just 36 degrees F. At 7-9 inches long (including their tail) these creatures have many larger predators to worry about, and most won’t live more than a year.

To help them survive, these mice have extremely long hind feet that allow them to jump up to 3 feet to safety. Not only are these little mammals great jumpers, they are also accomplished diggers and swimmers. In fact, this species prefers the grassy areas near water. The meadow jumping mouse will reemerge in mid to late spring to nibble on fruits, seeds, insects, and fungi.

Did you know? The meadow jumping mouse is the only mammal with eighteen teeth.

Learn more: Animal Diversity Web

As you’ve watched the many hairy, downy, and pileated woodpeckers at CWES hunt for insect meals this fall, perhaps you’ve wondered how they keep their bird brains safe while hammering away at speeds of 15 mph?

Woodpeckers have several helpful adaptations working for them. First, their sturdy prop-like tail helps stabilize their entire body as they chisel away. Secondly, the woodpecker’s skull is made of thick, spongy bone that encloses their brain so tightly that it doesn’t rattle about while hammering. Lastly, they have thick neck muscles and cartilage at the base of their lower beak that absorb the shock of their blows.

Did You Know? Some woodpeckers have tongues that are longer than their bills and wrap around their skull, beginning at their upper beak, extending around the back of their skull, and ending in their mouths. Many woodpeckers also have tongues with barbed ends for spearing insects, and produce a glue-like saliva to ensure that their meal reaches their mouths.

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