Live Long and Prosper

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.

Mourning Cloak are one of the larger butterflies, with a wingspan of four inches (10 cm). Photo by Pavel Kirillov from St.Petersburg, Russia, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0&gt;, via Wikimedia Commons.

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.

A Mourning Cloak female laying eggs on a Willow leaf (Salix spp.). Notice how camouflaged she is on the underside. Her wings are up when resting, and she blends in beautifully with tree bark. Photo by Jacy Lucier, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0&gt;, via Wikimedia Commons.
 

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.

Watch out for those stinging spines on Mourning Cloak caterpillars! It is a good defense for not being eaten by predators. Photo by Hectonichus, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons.

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.

Behold the Timberdoodle

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.

You can see how camouflaged this American Woodcock would be against the leaf litter, making it virtually impossible to spot. Notice also how far back its eyes are on its head. Photo by guizmo_68, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0&gt;, via Wikimedia Commons.

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.

A Flower Called Hope

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.

Common Snowdrops (Galanthus nivalis) in bud next to my back door, just after the snow melted. Photo by the author.

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.

A close up of the Common Snowdrops flower. The flower has three long, curved tepals (undifferentiated between petals and sepals) and three smaller, hooked tepals. Photo by Andreas Eichler, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0&gt;, via Wikimedia Commons.

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.

Distribution map of Galanthus species. Even with a wide distribution, Common Snowdrops (G. nivalis, #1 on the map) is threatened in the wild, like many species. Image by Nalagtus, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0&gt;, via Wikimedia Commons.

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.

Stories in the Snow

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!

White-tailed Deer tracks point toward the direction of travel, so this deer was traveling toward the bottom of the photo. Photo by Virginia State Parks staff, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0&gt;, via Wikimedia Commons.

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 tracks of the Eastern Gray Squirrel are square-shaped and are usually found going from tree to tree. Photo by
Ryan Hodnett, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0&gt;, via Wikimedia Commons.

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.

Notice the large hind feet on the track of this Eastern Cottontail Rabbit. When running, the rabbit’s large hind feet extend over the smaller front feet. Photo by Ian Muttoo from Mississauga, Canada, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0&gt;, via Wikimedia Commons

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.

American mink tracks, like most Mustelids, usually show the feet side by side. Notice the claws on each foot.
Cards are from Trakards for North American Mammals by David Brown. Photo by Gail Cameron.

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.

Unlike domestic dog tracks, which show the animal going back and forth and here and there, Red Fox are more determined and their tracks often show them traveling in a straight line. Photo by Gail Cameron.
North American River Otters love to slide down hills in the snow. Photo by Gail Cameron.

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.

The tracks of Eastern Coyote, like most members of the dog family, show their claws in snow or mud. Notice the triangular heel pad with two lobes at the bottom. Photo by Unknown (Fish & Wildlife Service employee), Public domain, via Wikimedia Commons.

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.

Bobcats have retractable claws so they won’t show in a track. You can just barely make out the three-lobed heel pad in this photo. Photo by Joe Decruyenaere, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0&gt;, via Wikimedia Commons.

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.

A real clue found in the snow. A hawk has landed and grabbed a Ruffed Grouse (Bonasa umbellus).

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

Pecking Order

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.

Due to habitat loss, the Red-headed Woodpecker is an endangered species in Connecticut. Photo by Jim Hudgins/USFWS.

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.

A male Yellow-bellied Sapsucker with freshly drilled sap wells. Male sapsucker have a red chin and females have a white chin.
Photo by USFWS – NE Region.

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.

A female Red-bellied Woodpecker about to feed her chick. Females can be told apart from males by having the red cap on the back of head vs. over the top of the head for males. Photo by Kozarluha, CC BY-SA 3.0 <https://creativecommons.org/licenses/by-sa/3.0&gt;, via Wikimedia Commons.

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.

A colorful female Northern Flicker. Northern Flickers like to hunt insects, especially ants, on the ground. Photo by
Nature’s Pic’s (www.naturespicsonline.com), Attribution, via Wikimedia Commons

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.

Connecticut’s largest woodpecker, the crow-sized Pileated Woodpecker. The black “mustache” coming off of the bill makes this a female. In males this field mark is red. Shenandoah National Park from Virginia, Public domain, via Wikimedia Commons.
Large, rectangular holes like those on this Spruce tree (Picea sp.) are a sign that a Pileated Woodpecker has been searching for carpenter ants.

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.

In the Dead of Winter, A Flash of Fragrance

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.

Signs of twigs ripped irregularly off the plant by White-tailed Deer (Odochoileus virginianus). Photo by BioKIDS, University of Michigan, http://www.biokids.umich.edu.
Twigs chewed on by Eastern Cottontail Rabbits (Sylvilagus floridanus) are characteristically cut on a 45 degree angle. Photo by BioKIDS, University of Michigan, http://www.biokids.umich.edu/.

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.

Black Birch (Betula lenta) bark on a mature tree. Notice the small horizontal lenticels and large, long vertical cracks. Photo by the author.
Black Birch twigs are thin, smooth, medium-brown with whitish pores (lenticels). Leaf buds are alternate, pointed and light brown. Scratch and smell that wintergreen flavor! Photo by the author.

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.

Yellow Birch (Betula allegheniensis) bark is a rich, golden brown with some curly strips hanging from it. Photo by Peter M. Dziuk, Minnesota Wildflowers.
Yellow birch twigs look very similar to black birch twigs, but can be more grayish and new buds are hairy.
Photo by Peter M. Dziuk, Minnesota Wildflowers.

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!

Tree of Heaven’s (Ailanthus altissima) stout twigs are as thick as your thumb. Notice the heart-shaped leaf scars. Photo by AnRo0002, CC0, via Wikimedia Commons.

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.

Black Cherry (Prunus serotina) bark looks like burnt potato chips. Photo by JDMcGreg, CC BY-SA 3.0 <https://creativecommons.org/licenses/by-sa/3.0&gt;, via Wikimedia Commons.
Black cherry twigs are shiny, gray- to reddish-brown and often developing a flaky, waxy, whitish covering. Photo by Peter M. Dziuk, Minnesota Wildflowers.

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.

Mature Sassafras (Sassafras albidum) bark has deep, vertical crevices with horizontal “hatchet marks.” Photo (c)2006 Derek Ramsey (Ram-Man), CC BY-SA 2.5 <https://creativecommons.org/licenses/by-sa/2.5&gt;, via Wikimedia Commons.
Sassafras twigs are green and usually come off of the main trunk at a 60 degree angle. Photo and hand by the author.

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.

Spicebush (Lindera benzoin) is a multi-stemmed shrub with light brown bark and bright white pores (lenticels). Photo by the author.
Spicebush twigs are olive-brown with round, reddish flower buds. Photo by the author.

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.

They Really Aren’t Fleas

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.

Springtails are tiny. Here is a close up. Photo by Andy Murray, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0&gt;, via Wikimedia Commons.

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.”

This Cat Belongs Outside

While getting the mail at twilight recently, I was treated to a rare sight…a Bobcat (Lynx rufus)! It crossed the middle of the road about 25 yards (23 meters) away and stopped to stare at me. I heard cars approaching and didn’t want it to be hit, so I walked briskly toward the cat and it ran off into the woods. Some cats have learned to look both ways before crossing roads. Even so, car strikes are one of the leading causes of Bobcat mortality.

Bobcats are two to three times the size of domestic cats, and are so quiet and camouflaged they are rarely seen. They are most active and dawn and dusk. Photo by Vachovec1, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0&gt;, via Wikimedia Commons.

During the 1800s, Bobcats were rarely seen. Populations were probably quite low because of the widespread clearing of New England forests for sheep farms and charcoal production. Connecticut had a state bounty on these cats until as recently as 1971, but hunting and trapping seasons were discontinued over concerns that the species was facing extirpation. In 1972 the Bobcat was listed in Connecticut as a protected furbearer. As the forests grew back and hunting pressure abated, Bobcat populations have gradually rebounded.

Bobcats are medium-sized, stout-bodied felines about two to three times the size of a domestic cat. Males usually weigh from 18 to 35 pounds (8 to 16 kilograms) and are 32 to 37 inches (81 to 94 centimeters) long. Females are smaller at 15 to 30 pounds (7 to 14 kilograms) and 28 to 32 inches (71 to 81 centimeters) long. These cats are gray to tan on their sides, with faint black spots. Bobcats are named for their short “bobbed” tail.

Although they are not often seen, the two white spots on the back of the ears are another filed mark for a Bobcat. Photo by Janarie Kay Ramelli, CC BY 4.0 <https://creativecommons.org/licenses/by/4.0&gt;, via Wikimedia Commons

Bobcats are polygamous (have more than one mate) and do not form lasting pair bonds. They mate in February and March and females raise the young, giving birth to one to four kits in April. Dens are located under fallen trees, in caves, on ledges, and in hollow logs.

For the past few years, Connecticut Department of Energy and Environmental Protection wildlife biologists have been studying Bobcats using radio telemetry. Cats are trapped, anesthetized, and fitted with GPS collars. Biologists had questions about Bobcat movement and home ranges as well as food preferences—and have discovered some surprising things. One female made a den next to an interstate. Bobcats are often hunting in woods near houses, but are so quiet that they are rarely seen.

A Bobcat track in the sand. Notice the lack of claw marks. Bobcats have retractable claws and claws don’t show when walking, in contrast with dogs and coyotes that have claws which don’t retract and show in the track. Bobcats have five claws on their front feet, but the fifth claw is further up the leg and doesn’t show in the track. Photo by Joe Decruyenaere, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0&gt;, via Wikimedia Commons.

By examining the stomach contents of road-killed animals, Connecticut DEEP biologists have found that Bobcats prey mostly on the Cottontail Rabbit (Sylvilagus floridanus), Eastern Gray Squirrel (Sciurus carolinensis), and American Red Squirrel (Tamiasciurus hudsonicus). Bobcats also hunt woodchucks, chipmunks, mice, voles, White-tailed Deer (Odocoileus virginianus—usually old, sick, or young animals), birds, insects, and reptiles. On occasion, they may also take small livestock and poultry, as well as unsupervised house cats. Other than making them potential Bobcat prey, it is never a good idea to let pet cats roam outside where they can contract the deadly feline leukemia virus. In the United States, free-roaming domestic cats kill up to 3.7 billion songbirds each year. Do Bobcats attack humans? Attacks on people are extremely uncommon and Bobcats rarely carry rabies. Bobcats should not be harmed.

In the last few years more people have reported Bobcat sightings. Despite increased development, populations in Connecticut now seem to be holding their own. Bobcats are very adaptable to living in a variety of habitats. They like mixed hardwood–coniferous forests, but seem to prefer younger forests with wetlands and brushy areas, or brushy woodlands with nearby fields.

Increasing urbanization, however, is fragmenting habitats. Bobcats in New England have a home range of 8 to 20 square miles (20 to 52 square kilometers). But animals in these fragments often are the most restricted in their movements, resulting in reduced natural genetic diversity. Preserving open space and providing wildlife corridors that connect available habitats are key to having these majestic animals with us for generations to come.

Something to Hoot About

I am a light sleeper. I was awakened before dawn the other day by a pair of Great Horned Owls (Bubo virginianus) serenading in a large spruce tree outside my window. The male’s deep, resonant but soft “whoo who-who-who whoooooo whoooooo” was immediately followed by the female’s slightly higher call, and they continued back and forth. It’s courting time for this species and now is a good time to hear them. You might need to wake early though as they seem to be most vocal between 3 and 6 am—although I have also heard them at dusk along the Farmington Canal Trail in Hamden.

Male Great Horned Owls set up territories in October. During courtship and before mating, the male will display in front of the female and bring her food. These owls are usually monogamous and often mate for life. After raising young, however, the pair may roost separately until the following winter although still in the same territory.

The pair won’t build their own nest from scratch. Here in New England these owls will commonly use old nests made by Red-tailed Hawks (Buteo jamaicensis), American Crows (Corvus brachyrhynchos), and even Eastern Gray Squirrels (Sciurus carolinensis). Females usually do the incubating. In Connecticut, a female Great Horned Owl sits on two to five eggs for 28 to 35 days, as early as late January to early February. Research has shown that females can successfully incubate eggs even when temperatures hit –27 °F (–32.8 °C)!

Can you find the Great Horned Owl? Look at the head peering toward you in the middle of this photo. Great Horned Owls usually don’t nest in cavities. I suspect that this is not a true hole but a “platform” where a limb broke off. Photo by Greg Schechter from San Francisco, USA, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0&gt;, via Wikimedia Commons.

Why nest in the cold depths of winter, which seems to be such a hardship? The Great Horned Owl is such a large bird that nesting early gives it a head start on lots of food for growing owlets in early spring right when prey is more active. It also gives young enough time to learn to hunt before the next winter.

Here is a female with one of her owlets in a nest created where a limb broke off. Notice the owlet’s adult plumage developing around its eyes. Photo by Andy Reago & Chrissy McClarren, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0&gt;, via Wikimedia Commons.

This nocturnal owl is such an efficient predator that it is called “the tiger of the skies.” With adaptations like fringed feathers on its primaries, a wing span up to five feet (1.5 meters), extremely strong talons, incredible hearing, and large eyes with sharp vision in low light, it can fly almost silently and dive down on prey. Its eyes are among the largest of all terrestrial vertebrates, about the size of those of humans. They feed on a wide variety of prey, including small mammals such as rodents, hares, and rabbits, other owls, waterfowl, and marsh birds. And they are one of the few predators of the Striped Skunk (Mephitis mephitis).

Great Horned Owls have eyes about as large as humans. The feather tufts are not ears. Notice the flat, rounded facial discs, which focus sound toward the ears, which are hidden near the black stripes a the edge of the discs. Photo by Jon Nelson, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0&gt;, via Wikimedia Commons

The name “Great Horned Owl” is a misnomer. They don’t have horns. What they do have are actually large feather tufts. These feathers can indicate their disposition. When the Great Horned Owl roosts during the day, the tufts are often in a narrow, elongated position with upright feathers, a camouflage adaptation that looks like a branch. This might keep the owl from being detected by crows. Crows mob owls, as owls have been known to eat crows. When I see a murder of crows flying quickly in circles and calling excitedly with harsh “caws,” I know they’ve found a predator, usually a hawk or owl.

Great Horned Owls are found throughout North America, from the subarctic in Canada and Alaska down to Mexico. They are highly adaptable to a variety of habitats, from deciduous, coniferous, and mixed forest, to prairies, mountainous areas, rocky coasts, and mangrove swamp forests, to urban areas. If you’re lucky enough to hear them at this time of year, you’ll know they are likely courting. When much of the natural world around us seems dormant, it’s pleasant to think of new life poised to begin anew.

Autumn Calls of Spring Peepers

Many people associate the call of peepers, the smallest frog in Connecticut, with the arrival of spring. Recently, while hiking on a warm fall day, I heard the “peeping” of Spring Peepers (Pseudacris crucifer). It wasn’t the huge chorus you usually hear at vernal pools and shallow ponds in March and April. It was just a few individuals calling back and forth. Instead of at the water’s edge, the sounds were coming from under the leaf litter. Why call in the fall, when it is not the mating season? Are these a different species?

A Spring Peeper (Pseudacris crucifer) calling in the spring. This tiny, one-inch (2.54cm) frog has a huge voice. Look at the size of its throat pouch! Photo by Justin Meissen, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0&gt;, via Wikimedia Commons.

I also checked out a vernal pool where I know Wood Frogs (Rana sylvatica) call in spring. There was actually a small chorus of them “quacking” in the leaf litter near the water. What’s going on?

Wood Frogs (Rana sylvatica) burrow into leaf litter in the fall and can actually freeze part of their body through the winter. They then “thaw out” and emerge to breed in vernal pools in the early spring. Photo by Peter Paplanus from St. Louis, Missouri, CC BY 2.0 <https://creativecommons.org/licenses/by/2.0&gt;, via Wikimedia Commons

Spring Peepers, and sometimes Wood Frogs, can actually be heard calling in the fall. The Spring Peeper’s autumn calls sound a bit harsher and more abbreviated, with less of the sleigh bell-like chorus that you hear in the spring. Lang Elliot, a biologist who has recorded many sounds in nature, captured the calls of fall peepers.

Both Spring Peepers and Wood Frogs are getting ready to go into a very deep sleep called torpor. Their bodily functions slow down and they go into a near-death-like state—part of their bodies actually freeze! Although the spaces between their cells can freeze, they prevent their cells from freezing by producing glucose, thereby keeping vital organs alive.

There are several hypotheses as to why these frogs are calling in autumn, but one has to do with environmental conditions. The shortness of the days, lower angle of the sun, increasing rainfall, and cooler temperatures are very similar to spring conditions when these frogs become active. Some may be responding to these environmental cues.

I asked frog biologist David Skelly, director of the Yale Peabody Museum of Natural History and Frank R. Oastler Professor of Ecology at Yale, about it. He said in autumn, the weather can be like the spring breeding period. “These environmental cues may prod them into calling, since they undergo physiological changes during late summer and fall that will enable them to breed as soon as they become active after a long period of dormancy.”

The name Spring Peeper is not a misnomer. Peepers are a sure sign of spring. But you may also hear them and their Wood Frog cousins in the autumn months as these tiny creatures get ready to launch themselves into the mating game.