Soon waves of migrating neotropical birds will pass through our area. They will be feeding furiously on hatching insects in the tree tops this May, but some have already arrived and have been here for weeks.

Eastern Phoebes (Sayornis phoebe) flew in from the southern United States and from as far south as Mexico, where about a third of these flycatchers spend the winter. Some Pine Warblers (Setophaga pinus) are permanent residents in Florida, Georgia, and the Carolinas. Many winter as far south as eastern Mexico and the Caribbean and migrate north in the spring. One of the most common wintering neotropical migrants where I sometimes vacation in southwest Florida is the Palm Warbler (Setophaga palmarum), a species that also winters in the Deep South and the Caribbean Islands.

Why do these insect-eating birds arrive so early? Eastern Phoebes come here as early as March, occasionally even when ponds are not free of ice. Pine and Palm Warblers arrive a few weeks later. It may be that arriving early is an advantage for these species that lets them claim open nesting territories. But this sometimes comes with a price. Late winter and early spring snowstorms could prevent them from finding food.

The large, explosive spring hatches of flying insects and moth larvae haven’t happened yet, so what are these birds feeding on? Most of the Eastern Phoebe’s diet is made up of flying insects, but they also eat spiders, ticks, and millipedes, and occasionally small fruits and seeds. Pine Warblers poke through bark, needles, and pine cones looking for dormant insects and early arriving birds are often seen searching through leaf litter for insects and other arthropods. They will also eat seeds and berries. Although Palm Warblers glean insects off tree bark and jump up for flying insects, they habitually feed on the ground and can even be spotted foraging there with sparrows. They will also eat bayberry (Morella pennsylvanica) and hawthorne (Crataegus spp.) fruits. So, an advantage these early migrants have is that they are adapted to finding food on the ground and eating fruits and seeds.

The Eastern Phoebe and Pine Warbler both nest in Connecticut, but the Palm Warbler is just passing through. It nests farther north usually on the ground in tamarack (Larix spp.) bogs of the boreal forest.

The Eastern Phoebe can be identified by its slate gray back and relatively large, dark head. It also wags its tail up and down. This bird gets its name from the song of the male: a raspy “fee-bee”.

The Palm Warbler also pumps its tail up and down. Both these birds and phoebes are among the few species that do this. The adult has a gray back, rusty coloring on the crown (top of the head), and rufous-colored streaks on its yellow belly. Its song, a weak, buzzy trill, is not frequently heard.

The Pine Warbler also has a yellowish belly, but its wings are gray with white wingbars and it has a yellow ring around its eyes. There are indistinct olive streaks on the sides of its breast. The male’s song is a long, liquidy trill.

Before migrating, these birds build fat reserves up to 50% of their body weight. Once these reserves are used during migration, the birds need to stop and refuel. Dave Ewert, senior conservation scientist with the American Bird Conservancy, describes three kinds of habitat that migrant birds look for.

“Fire escapes” are used in times of stress when birds are exhausted, starving, or disoriented. Under such emergency conditions, they stop at any habitat they can find. Small patches in urban and industrial areas can be fire escapes for migrants.

“Convenience stores” offer more abundant and higher-quality food and shelter, and are larger than fire escapes. Birds prefer them over fire escapes if they have a choice. Suitable habitats in parks, suburban gardens, and isolated rural woodlots are important convenience stores for migrants.

“Full-service hotels” are sites with the best habitat—plenty of nutritious food for refueling, safety from predators, and adequate shelter from inclement weather. These sites are natural areas, undeveloped rural lands, parks, and relatively large wildlife refuges.

Whether you live near a fire escape, a convenience store, or a full-service hotel, plant native perennials, shrubs, and trees that attract insects. Think of your yard or nearby park as a thing of beauty, not only because these plants are attractive to us, but because they are important refueling stops for these colorful birds.

I look forward each year to looking along streams to find one of my favorite spring wildflowers soon to be in bloom—Marsh Marigold (Caltha palustris). But it has an exotic cousin, a look-alike that threatens its existence and that of other native spring ephemerals such as Trout Lily (Erythronium americanum) and Spring Beauty (Claytonia virginica). It is Lesser Celandine (Ficaria verna).

Both Marsh Marigold and Lesser Celandine (also called Fig Buttercup, Pilewort, and Fig-crowfoot) are in the buttercup family, Ranunculaceae. They both have heart- or kidney-shaped leaves and yellow flowers.

So how do you tell them apart? Lesser Celandine’s leaves emerge really early in the spring, as early as February, and they are out now. When you are driving or hiking, look around to see what plants are in leaf. Many non-native invasives like Japanese Barberry (Berberis thunbergii) and Garlic Mustard (Alliaria petiolata) will leaf out before native plants, thereby outcompeting them for light. Check out stream and river banks and pond edges. Marsh Marigold is usually near the water’s edge. Lesser Celandine is more adaptable and can also be found in rich soils farther from water, even in sunny yards.

Lesser Celandine is a slightly smaller plant and flowers earlier than Marsh Marigold, usually in March or April here in Connecticut. If you see flowers on plants in late April to June, you can be almost certain it is Marsh Marigold. Marsh Marigold has 5 to 7 yellow tepals (undifferentiated petals or sepals), whereas Lesser Celandine has 7 to 11 yellow petals and 3 green sepals below the petals.

Invasive Lesser Celandine can form huge, extensive mats if left unchecked. The U.S. Department of Agriculture has predicted that it could establish itself in 79% of the continental United States. Now that’s an adaptable plant! It can do this because it forms tubers, which break off very easily through ground disturbance and flooding. After flowering, Lesser Celandine also forms bulbils in its leaf axils. This vegetative little bulb is a clone and can become a new plant.

How do you control this plant? If you have a small patch, try to eliminate it before it spreads into a monoculture. Control small patches by hand-digging the plant, making sure to sift out all tubers and throwing them in the trash. The tubers and roots are in the first 3 inches (about 8 centimeters) of the soil. Larger incursions are more difficult to control.

Marsh Marigold’s deep yellow flowers, larger than those of Lesser Celandine, are very striking near water. If you have a damp place in your yard in part to full sun, try growing it. It is sold at nurseries, particularly for plantings next to water or in rain gardens. Be sure to ask that the plants sold are nursery propagated.

Native plants like Marsh Marigold have spent thousands of years co-evolving with the pollinators in their ecosystem. Insects are co-evolved to feed on its leaves or gather its pollen and nectar. They in turn are fed on by birds. The nectar and pollen of the flowers of Marsh Marigold attract flies and bees, including the Giant Bee Fly (Bombylius major), syrphid flies, and halictid bees.

Yet, in a few decades, Marsh Marigold can be undone by non-native thugs like Lesser Celandine. By knowing the difference between the two and giving the native a chance to compete we can control the invasive and ensure a healthy ecosystem, even on a small scale like our own backyard or nearby streams.

Last fall I planted snowdrops (Galanthus spp.) and crocus (Crocus spp.) to have very early blooms available for the first pollinators that hatch in the spring. Even though these are not native, they do provide early nectar and pollen sources for native solitary bees. This would be before native plants such as Pussy Willow (Salix discolor) and Spicebush (Lindera benzoin), as well as spring ephemerals like Bloodroot (Sanguinaria canadensis) and Dutchman’s Breeches (Dicentra cucullaria), begin to flower. I am trying to gradually lose the lawn and to plant at least 70% native plants, as recommended by entomologist Douglas Tallamy in his book Bringing Nature Home (Timber Press, 2007).

Those spring bulbs I planted are in full flower now. I count at least three different species of bees hovering around  them. There is one standout in full force: a mason bee (Osmia spp.). Many of the species in this genus are polylectic, meaning they gather nectar and pollen from the flowers of different plant species. However, there are a few specialist mason bees that only like certain flowers. The Beardtongue Mason Bee (Osmia distincta) only visits the flowers of beardtongues (Penstemon spp.), whereas Osmia virga frequents blueberries (Vaccinium spp.).

There are about 20 species of mason bees in Connecticut. One of the most common is the Blue Orchard Bee (Osmia lignaria). Like many native bee species, however, it seems to be on the decline. Researchers from the Connecticut Agricultural Experiment Station have noticed that two non-native mason bees, the Japanese Horned-face Bee (Osmia cornifrons) and the Taurus Mason Bee (Osmia taurus), are displacing the Blue Orchard Bee. The Japanese Horned-face Bee was released in the Northeast to pollinate orchards. The Taurus Mason Bee, a very similar species, showed up soon after.

Scientists studying mason bees in the U.S. Mid-Atlantic states used pan traps to find out how common the two exotic and six native Osmia species have been over the span of 15 years, from 2003 to 2017. All the native species showed substantial annual declines ranging from 76% to 91% since 2003. The two exotic species fared much better—O. cornifrons was stable and O. taurus increased 800% since 2003. Scientists think these exotic species are outcompeting native species for nest sites and food sources. They may have also introduced parasites to native species.

Unlike Eastern Carpenter Bees (Xylocopa virginica), which as you probably know drill holes in wood, mason bees depend instead on holes and tunnels made by other insects and by birds. About 30% of our native bees are tunnel nesters.

Mason bees are a little smaller than honeybees. They are not aggressive. The male doesn’t sting and the female will only sting if handled roughly. Adult females collect pollen and nectar to feed their young. A female will pack this pollen and nectar into “bee bread,” deposit it into a chamber, and lay an egg next to it. There are five to eight of these brood cells in each tunnel. She lays an unfertilized egg, which will be a male bee, at the end of the chamber closest to the outside. When the eggs hatch, the larvae feed on the pollen and nectar stored in the nest. After 10 days, each spins a cocoon and becomes a pupa in its cell. By the end of summer the bees transform into adults, a stage called an imago, but remain in their cocoons throughout the winter.

Males hatch first in the spring. They wait outside the tunnels and mate with females when they hatch. Mating is their sole purpose. Female mason bees live about one month, males much less.

Mason bees are incredibly effective pollinators. Unlike honeybees, which aren’t up and about early in the morning, mason bees are out both early and late. Apple farmers know how efficient and effective these pollinators are and have created bee boxes for them. You can too and now is the time to put them up. Like bird boxes, bee boxes are mostly for your enjoyment. They are not a necessity for the bees, since they can find tunnels in the wild.

You can make your own mason bee box by drilling holes in a block of wood. The holes should be between a quarter inch (6 mm) and three-eighths inch (9.5 mm) in diameter and 6 inches (15 cm) deep. Keep the holes closed at one end. You can also buy a mason bee nest box at specialty stores like the Fat Robin Wild Bird and Nature Shop in Hamden, Connecticut. Another way to create your own box is by cutting off the lower stems of invasive Phragmites grass (Phragmites australis), tie them in a bundle, and plug the hole on one side with plastic wood filler or something similar.

The best location for a bee nest box is in a dry, protected place with an eastern or southeastern exposure. In the fall you can use a paper straw liner, inserted into each hole, to retrieve the cocoons to “wash” your bees. This will get rid of most of their mites and diseases. Clean the cocoons between October and December, because the adults are fully formed by then.

First, soak the cocoons in cool water to soften and remove mud. Be sure to use water no warmer than 50 °F (10 °C), so you don’t “wake up” the bees. Using a sieve, gently roll and move cocoons through the water. Discard any debris. Next, soak the cocoons, for no more than 10 minutes, in cool water with a 0.05% bleach solution (1 tablespoon bleach per 1 gallon water, or 15 milliliters of bleach in 3.75 liters of water) to kill bacteria, fungi, and most mites. Rinse well under cool water to remove all traces of bleach. Dry on a clean paper towel for one hour. Sort and discard damaged, diseased, or parasitized cocoons. Put the cleaned, air-dried cocoons in a small container with air holes and store this in your refrigerator for the winter. When you see bees flying around your garden in the spring, open the box outside in a sheltered location. See the comprehensive, free online book called How to Manage the Blue Orchard Bee by Jordi Bosch and William P. Kemp (Sustainable Agriculture Network, 2001) for more information.

Many of our pollinators are undergoing population declines. You can help mason bees by providing native trees, shrubs, and perennials in your yard. Try to have a variety of plants in bloom from early to mid-spring, when the bees are active. Other plants these bees will also visit are Redbud (Cercis canadensis), oaks (Quercus spp.), Black Willow (Salix nigra), Beach Plum (Prunus maritima), and shadbush (Amelanchier spp.), and many more. If you have to cut down a tree, consider leaving 10 to 20 feet (3 to 6 meters) of the trunk that can become nesting sites and tunnels for mason bees. We can all do our part.

During the brief interlude of spring-like weather we had recently, even with patches of snow still on the ground, I spotted a butterfly flitting through the forest. It was a Mourning Cloak (Nymphalis antiopa), named long ago for its dark-brownish black wings colored like the cloak of a person in mourning.

How could this butterfly have gone through its life cycle—from egg to larva (caterpillar) to chrysalis to adult—in this cold weather? Well, it didn’t. The Mourning Cloak is one of the few butterflies that overwinters as an adult, taking shelter under bark or in a tree cavity.

How do they survive the cold? They go into diapause, a dormancy many insects undergo in which their systems shut down and their bodies produce glycerol, a kind of antifreeze that protects their vital organs from freezing. Most insects overwinter as eggs, as larvae or as pupae (the resting stage known as a chrysalis in butterflies and as a cocoon in moths).

Mourning Cloaks live long compared to most butterflies—up to 12 months. That they overwinter might be one reason. When the adults emerge in late winter or early spring, they will warm up in sunny patches. They also turn their bodies to the sunlight to absorb heat.

These butterflies emerge when few flowers are in bloom. Flowing tree sap, with sugars and proteins, are an important early food source for Mourning Cloaks. Later they feed on ripe and fallen fruits as well as the sugary exudate from aphids. They don’t seek nectar as much as many other butterfly species, but I have seen them nectaring on the catkins of Pussy Willow (Salix discolor) and Black Willow (Salix nigra). This is yet another reason to include native shrubs and trees such as these in your landscape. Native willows are an important early pollen source for many native bee species too.

Mourning Cloak males will look for an appropriate territory, a prime location to attract a female. On mating, the female will lay her eggs on leaves of larval host plants: willows, American Elm (Ulmus americana), Hackberry (Celtis occidentalis), ashes (Fraxinus spp.), poplars (Populus spp.), and birches (Betula spp.). They hatch about 12 days later. In early stages the larvae group together in a web, perhaps an adaptation for protection against predators. The caterpillars are black with spines and rows of red dots running down the center of the back, which might be aposematic, a warning coloration. If handled, those spines can sting.

After undergoing five instars (larval growth stages and sheds), the Mourning Cloak spends about two weeks as a chrysalis, before eclosing, or emerging as a butterfly in mid-summer. Adults who lived through the previous winter then die. This new brood is the future of the species.

How can you help this butterfly and other important insects to live long in your yard? Try to garden naturally without using pesticides. Don’t use butterfly boxes. They really don’t work and actually attract hornets, which can prey on butterflies. Allow a “messy” section in your yard, with bark and leaves for overwintering sites. Plant native trees and shrubs such as those mentioned here. We all can do our part to help this striking butterfly and many other important species to prosper.

Labrador Twister. Bogsucker. Mudsnipe. Hokumpoke. Timberdoodle. These are just some of the colorful names for the American Woodcock (Scolopax minor), a robin-sized, inland shorebird whose courtship displays, unknown to most of us, are an amazing spring phenomenon. It’s now time to listen for them.

Newly arrived from its wintering grounds in the southern United States, now (mid-March through the beginning of April) in Connecticut is the time to check out the males’ courting grounds. Prime courting habitats are fields with scattered mixed shrubs or open fields near woodlands, particularly near wetlands. A good way to find woodcocks is to go to a good habitat at dusk and listen for the male’s nasal, buzzy “peent.” If you listen closely, you can hear a gurgling note before the “peent” call.

But that’s just the beginning. If you spot him, you’ll see the male then spiral upward, with a fast twittering sound caused by the air going through his three primary feathers. As the bird drops rapidly to the ground, he’ll make a loud, chirping, “kissing” sound along with the twittering. This chirping or “kissing” is done vocally. He is silent when landing. He’ll begin again if he has not been successful in attracting a female. This display will continue for a half hour to an hour.

After mating, the female will lay one buff-colored, brown-blotched egg per day (for an average of four), typically in a depression among dead leaves. Incubation takes 19 to 22 days. When the young hatch, they are precocial, able to walk within few hours. They soon learn to freeze when they hear their mom’s alarm call. They grow quickly and can fly short distances after only a few short weeks.

The timberdoodle has evolved some fascinating adaptations. It has a mottled, tawny, camouflaged brown coloration with a “deaf leaf pattern” that is almost impossible to see when the bird is motionless. Its squat body has an extra-long bill, perfect for probing the ground for earthworms, about 60% of its diet. A woodcock can eat up to its weight in earthworms in a day! These birds also eat crustaceans, grasshoppers, beetles, caterpillars, and more.

Woodcocks often “strut” when walking. It has been theorized that stepping heavily while bobbing back and forth causes earthworms to move, signaling the location of potential prey. I got a chuckle when someone set a video of this bobbing to funk music.

Most people think of a bird beak as being hard, but the American Woodcock’s bill is flexible at the tip and can open to grab earthworms even while probing the ground. Why have such a long bill on a small body? One theory is that, through time, the bill lengthened, the eyes moved more to the sides of the head, and the nostrils moved closer to the base of the bill, all to enhance its probing ability.

In some years, woodcocks arrive from wintering grounds only to experience late snow and ice storms. These weather events prevent them from finding food, leading to population losses. They are also particularly vulnerable to habitat changes. Steadily increasing urbanization as well as the maturing of forests are causing a decline in American Woodcock populations. And free-roaming domestic cats kill millions of ground-nesting birds like woodcocks every year.

It is vital that our forests be managed for trees in a range of different age classes to encourage wildlife diversity. A diverse woodland with sections exposed to full sunlight provides one of the best habitats for food and shelter. Active management of these habitats will enable the continued survival of wildlife like these unique birds, which deserve their place in our landscape.

At this time of year many of us are on the lookout for whatever signs of spring we can find. The first true, native wildflower of spring, Eastern Skunk Cabbage (Symplocarpus foetidus), has been in bloom among swamps and streams for weeks now. But the first harbingers of spring in many of our yards and gardens are the snowdrops (Galanthus spp.). Seeing this flower in bloom gets the blood flowing with the realization that spring will soon arrive. I just found it in bud at my doorstep after the snow melted.

The name of the genus Galanthus is from ancient Greek (gála, milk, and anthos, flower). The most commonly cultivated species, the Common Snowdrop (Galanthus nivalis), aptly translates to “the milk flower of the snow.” This is the species that has been in cultivation for years and is the one that most of us have in our gardens.

The Common Snowdrop grows in the wild in woodlands and by streams in almost all of Europe, except England, Scotland, Ireland, and Wales. It was probably introduced in England in the 16th century. Some Brits, known as galanthophiles, are absolutely mad about their snowdrops. There are now more than 2,500 varieties and hybrids. In 2015, one plant, Galanthus ‘Golden Fleece’, sold on eBay for 1,390 pounds (US$1,940)! During the Second World War, US military police stationed in England were called snowdrops by the British because of their green uniforms and white hats and gloves.

Snowdrops are members of the Amaryllis family, Amaryllidaceae. They, like Trout Lily (Erythronium americanum), are true spring ephemerals, franticly flowering in late winter’s bright light and then withering away. But, unlike Trout Lily, they are not native New Englanders, having jumped ship from the Old World.

There are about 20 species throughout Europe and Asia and new species are still being identified. The most recent was discovered in 2012, Galanthus panjutinii. It is endangered, and only found in Georgia and Russia. One population was destroyed during preparations for the Olympic Games in Sochi. Many species are threatened from habitat loss, over-collecting, and climate change. So, it is best to stick with varieties that have been in the trade for a while and are nursery propagated.

Reproduction in snowdrops mainly occurs with the bulbs creating offsets, as these plants bloom so early there aren’t many pollinators out yet. The occasional early-emerging queen bumblebee might pollinate a few flowers. If that happens, capsules form with seeds that contain hooked elaiosomes, which are attached fatty packets that attract ants. Ants then carry the seeds to their nest, eat the elaiosomes, and put the seeds in their dump pile, thereby planting the seeds.

You can take advantage of bulb offsets by dividing snowdrops when they are “in the green,” just after flowering. Dig up the whole plant, bulbs and all, separate it into smaller clumps, and then plant those. You can quickly have good-sized patches in a relatively short time.

During the 19th century, in both England and the United States, the cultural practice called floriography, or “the language of flowers,” was all the rage. It’s a way to communicate using flowers, and we still do it today, with red roses that symbolize love and yellow roses for friendship. Snowdrops represent hope. In this time of division and hardship, let’s celebrate the hope that comes with increasing light and warmth and better days ahead.

It’s been a snowy February. But it’s late winter and there is a thaw beginning this week with daytime temperatures in the 40s (4 to 10 degrees C). While the snow remains, it’s a good time to take a walk and see what wildlife has been up to.

Many mammals in our area are active all winter long. During snowstorms, White-tailed Deer (Odocoileus virginianus) gather or “yard up” under coniferous (cone-bearing) trees like pines (Pinus spp.) and spruces (Picea spp.), where the green leaves block snow from accumulating below. Their hoof prints are easy to tell apart from other tracks. The hoofs are from 2 to 3 inches (5 to 7.5 centimeters) long, and wider at the bottom than the top, so this pyramid-shaped track points in the direction of travel. Follow the tracks and you’ll find they are going to young trees and shrubs to nibble on buds and bark. Many New England states are overpopulated with deer. Once there is snow on the ground, you really can see how many are around and where their trails are. You’ll then think it’s time to put repellent on the buds and branches of your small trees!

After a storm, and when the temperatures warm up a bit, Eastern Gray Squirrels (Sciurus carolinensis) come out of their tree cavity roosts and nesting sites to look for their caches of buried nuts. Occasionally you’ll see a hole in the snow where they’ve dug to get at them. If you spot lots of square-shaped tracks that go from one tree to another, you’ve found this animal. In the squirrel’s track, you’ll see that the larger back feet are in front with the smaller front paws directly behind. This is because, when the squirrel runs, the front feet thrust forward and the back feet land in front and afterward.

The track of a White-footed Mouse (Peromyscus leucopus) is tiny, only one-quarter inch (0.63 centimeter) wide, and look like squirrel tracks, as it is square-shaped too. Mice will hop or run on the snow’s surface, but then often tunnel underneath to the subnivean zone, the layer between the ground and the snow, where they look for seeds and other food.

The T-shaped tracks of the Eastern Cottontail (Sylvilagus floridanus) are unique. These rabbits place their 1 inch (2.5 centimeter) front feet one in front of another, then their large, 3 inch (7.5 centimeter) long back feet pass over their front feet to make its distinctive track.

Most of the members of the malodorous mustelid family (that’s the musky-smelling weasel family) also leave square tracks, but unlike squirrels, their front and back feet are about the same size and placed down in pairs. You can tell the small Short-tailed Weasel (Mustela erminea) from the medium-sized American Mink (Neovison vison) and the large North American River Otter (Lontra canadensis) by the track size, the straddle (distance between the feet), and stride (distance from one track to another). Look for tracks of mink and otter along streams and ponds, where they hunt for fish and crayfish. Both mink and otter are playful and will create snow slides on small hills near water.

The Red Fox (Vulpes vulpes) listens for mice under the snow. When the snow is really deep and powdery, a fox will jump up and plunge into it vertically headfirst to grab a mouse. Like the tracks of other canines (members of the dog family) whose claws are not retractable, a fox’s track will show all its claws. Red Fox tracks average 2 inches (5 centimeters) long and wide. Foxes and coyotes are all diagonal walkers, placing their back feet in the same place as their front feet.

Eastern Coyote (Canis latrans) tracks are larger than those of the Red Fox, averaging 2.5 inches (6.35 centimeters) long by 2 inches (5 centimeters) wide. You can distinguish fox and coyote tracks from domestic dog tracks by the evidence of the animal’s behavior. Foxes and coyotes are determined when trotting and hunting, and walk in a straight line. In contrast, domestic dogs playfully wander to and fro, examining and smelling their surroundings. You can see that behavior in their tracks. Look for human tracks near them too.

Bobcats (Lynx rufus), like coyotes, foxes, and deer, are diagonal walkers too. How do you tell Bobcat tracks from those of coyotes, which are close in size? Unlike members of the dog family, a Bobcat has retractable claws, so you won’t see them in the track. They also have three-lobed heel pads, compared to two-lobed coyote heel pads. Bobcat tracks are slightly smaller than those of coyotes, about 1.5 inches long (3.8 centimeters) and one and three-eighths inches (3.5 centimeters) wide.

Even birds of prey leave signs in the snow. Look for a flurry of wing marks in the snow where a hawk or owl has grabbed a bird or mouse.

Be on the lookout for the stories that the snow can tell you.

At this time of year, the bare branches of winter reveal secrets unseen in summer’s leafy canopy. It’s a good time to see where nature’s drilling crews, the woodpeckers, have done their work.

There are seven species of woodpecker in Connecticut, and they all excavate cavities in trees to nest. Because of habitat loss, one of them, the Red-headed Woodpecker (Melanerpes erythrocephalus), is a Connecticut Department of Energy and Environmental Protection listed endangered species. Farmland, with groves of mature trees in old fields, and wooded swamps are decreasing. Competition for nest cavities with European Starlings (Sturnus vulgaris), a non-native species that outcompetes and displaces this woodpecker, is also a factor. Try to discourage starlings from using nest boxes and cavities.

Most species of woodpeckers excavate a new nest cavity each year, usually in a dead tree or in a dead branch of a living tree. You can often tell the woodpecker species by the size of the entrance hole, which is based on the size of the bird.

The Downy Woodpecker (Picoides pubescens), our smallest species, excavates a round hole 1 to 1.5 inches (3.8 centimeters) across. Its slightly larger cousin, the Hairy Woodpecker (Leuconotopicus villosus), makes a hole that is 2 inches (5 centimeters) in diameter. Even though Downy and Hairy Woodpeckers often live in the same forest habitat, they don’t compete with each other. In this niche partitioning, Downies hunt for sleeping insects in small crevices and will often crawl out on small branches, whereas Hairies peck more deeply into the bark along the larger trunk for wood-boring insects and their larvae. Here’s a video of a female Downy feeding her young in New York’s Central Park.

Yellow-bellied Sapsuckers (Sphyrapicus varius) chisel out a nest hole that is the same size as that of a Downy Woodpecker. But there is an easy indicator that they have been around. If you find rows of small, horizontal holes in a tree, you’ve found where a sapsucker has been. They usually create these drill wells in trees with sap that has a high sugar content, like maples and birches, and later will return to lick up the sap (they actually don’t suck sap). Maybe this bird should be called the Yellow-bellied Saplicker? They lick sap year-round, but will switch to a higher protein insect diet in summer.

Unlike most woodpeckers, Yellow-bellied Sapsuckers prefer to nest in live trees, especially the soft wood of Big-toothed Aspen (Populus grandidentata). Sapsuckers help other birds too. Ruby-throated Hummingbirds (Archilochus colubris) depend heavily on sapsucker drill wells as they migrate north in the spring.

The Red-bellied Woodpecker (Melanerpes carolinus), originally a bird of the southern United States, has moved into Connecticut in the last 50 years. Its nest hole is about 2.5 inches (6.3 centimeters) in diameter. Interestingly, this bird drills acorns and other nuts into bark and will later return to feed on its cache.

The Northern Flicker (Colaptes auratus), Connecticut’s second largest woodpecker, chisels out a nest hole with a diameter of 3 inches (7.6 centimeters). Unlike most woodpeckers, flickers often return to a successful nest site in later years. I once found an active flicker nest. The pair had chosen their nest site well. Just above the entrance hole was a bracket fungus, which created a nice canopy to shield the cavity from harsh weather. I’ll bet that pair has returned year after year.

The last, but certainly not least, woodpecker species is the largest in North America—the Pileated Woodpecker (Dryocopus pileatus). A larger woodpecker, the Ivory-billed Woodpecker (Campephilus principalis), is likely now extinct.

Pileated Woodpeckers create a round entrance hole that is 3 to 4 inches (7.6 to 10 centimeters) across. Most people think that the large, 4 inch by 6 inch (10 by 15.2 centimeter) rectangular holes that Pileated Woodpeckers make are nest holes. They are actually the woodpecker’s excavations to reach its favorite food: Black Carpenter Ants (Camponotus pennsylvanicus). Pileated Woodpeckers need a mature forest habitat of 150 to 200 acres.

Woodpecker cavities are important nesting and roosting sites for other wildlife too. Animals that use woodpecker cavities include the Deer Mouse (Peromyscus maniculatus), White-breasted Nuthatch (Sitta carolinensis), Eastern Gray Squirrel (Sciurus carolinensis), American Red Squirrel (Tamiasciurus hudsonicus), Southern Flying Squirrel (Glaucomys volans),Northern Flying Squirrel (Glaucomys sabrinus), Eastern Screech Owl (Megascops asio), and American Kestrel (Falco sparverius).

Did you know that you can create woodpecker habitat in your yard? Where I live, we’ve had some severe storms in the last few years that have resulted in a lot of snags and downed trees. I’ve also lost six American Ash trees (Fraxinus americana) in my yard from the Emerald Ash Borer (Agrilus planipennis). As long as the trees aren’t in any danger of falling on someone, you can create amazing wildlife habitat just by leaving snags in your yard. I had the tree company remove the top of each tree, but limb up and leave the bottom 20 feet (6 meters). All the insects and other decomposers tunneling into the bark and wood have “set the dinner table” for a whole host of woodpeckers.

Woodpecker nest box plans that you can make to attract these amazing birds to your yard are available online. Also, keep track of any woodpecker cavities you find near you and see what might use them this spring. You can install a trail camera and point it toward that hole. You might just be surprised what you see.

When leading nature walks in winter, I like to point out that nature is not dead, only resting and waiting for the rebirth of spring. Even now, there are plenty of things to see and do in the winter woods.

On your next outdoor walk, try looking for signs of herbivores. White-tailed Deer (Odochoileus virginianus) are now feeding on the twigs and buds of trees and shrubs. They can eat up to 4 pounds (1.8 kilograms) a day! The twigs eaten by deer are ripped off the plant in a highly irregular way. In contrast, twigs eaten by the Eastern Cottontail Rabbit (Sylvilagus floridanus) are usually bitten off at a 45-degree angle, lower to the ground of course.

Deer will generally avoid twigs that are fragrant, such as Sassafras (Sassafras albidum). They will, however, eat supposedly “deer resistant” plants if they are really hungry. Why are some twigs fragrant? Not only does scent repel vertebrate herbivores, but these fragrant chemicals may have evolved as a defense against insects. It’s an evolutionary game of chess—plants create chemicals to repel predators, but sometimes predators co-evolve and are not harmed by them. Insects may even use these chemicals for their own defense.

We find many of these scents very appealing. Remember the scratch and sniff books for toddlers? Well, you can do that on your next walk. The trick is to identify those trees and shrubs that are scented. Just scrape a small section of the outer bark of a twig to get into the living cambium layer. Doing this on a few twigs will not harm the tree.

Do you like the smell of wintergreen? Try scratching and sniffing Black Birch or Sweet Birch (Betula lenta), as well as Yellow Birch (Betula allegheniensis). These trees have the chemical methyl salicylate, which is used to flavor many products, such as toothpaste and mouthwash. Because it is similar to salicylic acid, with aspirin-like properties, it is also used in topical rubs for muscle pain (think Bengay® cream). Originally, birch beer was also made from this bark. Most of these scents are now produced synthetically.

In the northeast, Black Birch is found growing on moist, acidic, wooded slopes, as well as in well-drained rocky areas. The mature bark is dark brown with many horizontal lenticels (pores that exchange gases) divided by many large vertical cracks. The twigs are very thin, smooth, and reddish-brown with sharp, pointed buds.

Yellow Birch twigs also have a wintergreen scent, although this is not as strong as in Black Birch. Yellow Birch twigs are slightly hairy in new growth and are grayer than Black Birch twigs. A mature Yellow Birch tree is easy to identify. Its shiny, yellow-bronze bark, also with dark lenticels, has distinctive peeling strips of curly bark. Yellow Birch grows in moist soils along cooler, north-facing slopes and stream banks.

If you live in a city or near disturbed woodland edges, there is a good chance that the invasive Tree of Heaven (Ailanthus altissima) is nearby. Its smooth bark and very thick, stout branches (as thick as your thumb) are easy to spot. You’ll know it when you smell its twigs. They smell like burned or rotten peanut butter!

Do you remember the Sherlock Holmes story in which the famous detective smells bitter almonds on a victim’s breath and determines that the person was poisoned? Eastern native trees in the cherry family, such as Black Cherry (Prunus serotina), Pin Cherry (Prunus pennsylvatica), and Choke Cherry (Prunus virginiana), all have a pungent bitter almond odor when scratched. This is because the twigs and leaves contain cyanide! Please don’t ever eat these leaves and twigs.

My favorite fragrances are from trees and shrubs in the laurel family, the Lauraceae, a tropical group with two members here in the north. Sassafras (Sassafras albidum) is found growing on dry, open woodlands and woodland edges and is a pioneer species in fields. Young trees are deep olive green with brighter green twigs. Sassafras tea was once made from its roots, but was found to contain safrole, which has been banned by the US Food and Drug Administration because of its possible carcinogenic effects. Its fragrance is citrusy and fruity. Some people think Sassafras twigs smell like Fruit Loops® cereal.

Spicebush (Lindera benzoin) is the other northern member of the laurel family. Spicebush grows in moist soils in wooded bottomlands and low swamps, and along streams. Its medium-brown twigs are smooth with characteristic round, reddish flower buds. When scratched, they are strongly aromatic, with a complex citrus, pepper, and pine scent.

Although in the midst of our New England winter we all miss the delightful perfume of summer flowers, don’t think that our woodlands are devoid of scent. Take a fragrance walk and you’ll be pleasantly surprised.

It seems to me that, in the past few years, each winter we have less and less snow cover. I wonder if it’s a long-term trend because of climate change. I am also curious about how this might affect the health of dormant plants and animals. A blanket of snow protects and insulates plant roots, keeping them from drying out in cold winter winds. Snow helps predators track and hunt, and mice and voles burrow under the blanket for protection.

Nearly all the snow has melted from the foot or so we received a few weeks ago. After a fresh snowfall I like to check out local natural areas in my neighborhood to see who’s been around. I miss doing that. But as the snow was melting, I did notice tiny twenty-fifth-inch to sixteenth-inch (1–2 mm) flecks peppering the snow. On closer examination, they were “Snow Fleas” hopping around next to a tree trunk.

Snow Fleas are not parasites and don’t bother you or your pets at all, unlike true fleas. But like true fleas, Snow Fleas can jump great distances for their size. For this reason, they are also called Springtails. They were once classified as insects, but now are in a separate group, in the subclass Collembola. Most species have a forked tail-like appendage called a furcula. It’s the furcula that acts like a spring, propelling them into the air.

How can Springtails be active in winter’s bitter cold? Springtails have antifreeze proteins that are rich in the amino acid glycine. This protein attaches to ice crystals as they form in their bodies and prevents the crystals from getting larger. Some scientists speculate that Springtails come up to the surface of the snow because of overcrowding, or possibly lack of food. They will, however, return to the leaf litter below. Springtails feed on fungi, pollen, algae, and decaying organic matter.

So as the next snowfall melts, look for tiny, pepper-sized “flecks” jumping around and be thankful for them. Just like many other decomposers, such as fungi, bacteria, isopods, and more, Springtails are vitally important in breaking down leaves and other organic material into soil beneficial to plants and, in turn, animals like us. As the biologist E. O. Wilson said, “It’s the little things that run the world.”