Nature news: Building a magical mound in my garden

published May 12 2020 on seacoastonline.com and in the York Weekly, York County Coast Star, Portsmouth Herald, Foster’s Daily

I moved just a little more than a year ago and have been thinking about and building vegetable gardens ever since-many didn’t work out so well. The garden I started out back turned out to be in the coldest, shadiest part of the property. (I should have realized this based upon the amount of moss growing there.) So, this spring I moved the garden to the front — a sunnier spot that wasn’t originally my first choice given its proximity to the road. But I have grown accustomed to this. In this time of coronavirus, I now have almost as many neighbors walking by and waving hello as I do cars. It’s a friendly place for a garden.

Hugelkultur bed. The bricks are decorative, but the logs on either side are an extension of the buried logs underneath–they’ll slowly rot, retain water and add nutrients and organic material to the soil….they are building soil.

I am trying to garden as close to nature as possible — to work with nature, use nature as my guide and inspiration. My newest gardening adventure concerns something called hugelkultur, a word that means hill, or mound, culture. What I love most about it is that it is so obvious — its premise underlies natural soil formation. A tree falls in the forest, whether or not anyone hears it fall, it will eventually turn into soil. Hugelkultur beds use rotting logs as their base; the logs slowly release nutrients into the bed as they decay. So I recruited my son, quarantined back home, to help build a hugelkultur bed. He collected old logs from the forest, laid them on the ground and built a mound over them full of sticks (also from the forest), sod and straw, some compost, leaves and manure.

I was discussing my hugelkultur bed with my naturalist friend Steve Morello. He pointed out that there are more living cells in a dead tree than a living tree. In an article titled “Forest of the Living Dead,” Jenny Dauer of the Forestry Communications Group at Oregon State University asks, “Which is more alive: a live tree or a dead tree? If ‘alive’ means growing, breathing cells, a dead tree wins hands down. While only a thin layer of wood and bark are growing and actively transporting water and nutrients from roots to leaves in a live tree, all of a dead tree’s cells are teeming with insects, fungi, and bacteria. Some dead trees even have new plants and moss growing on them.”

Rotting wood is the basis of a healthy
forested ecosystem.

Walking in my woods this afternoon I thought about this — the sheer quantity of life found in one of those old standing snags or a downed log, slowly returning to dirt on the forest floor. It’s somewhat mind-blowing to realize that those snags and logs contain more life than the towering, living maples and hemlocks. Amazing to think that before that already partially-rotted standing dead tree hit the ground it was readying itself to release its nutrients back into the land, building soil.

The forest floor in my backyard is spongy with rot. Leaf litter and dead wood hide a vast network of lives dedicated to turning those dead leaves and wood into soil. Compare this to a typical garden bed. Most of my beds are wood frames filled with a mix of compost, manure and loam — very straightforward.

When I think of my hugelkultur bed, it seems magical in comparison — the logs buried in the bottom will start to decay over the next few years. The wood provides homes to the insects, bacteria and fungi that help with decomposition. It becomes spongy and holds onto moisture (a well-constructed hugelkultur bed needs to be watered only once every three weeks or so, at most). The decaying log provides warmth so that these beds can extend your planting season by a few weeks. What’s more, you are building soil with each mound you construct!

You can build hugelkultur beds in urban areas, a suburban backyard, even the desert. Try it! Bring a little nature into your backyard.

Nature News: The mating rituals of water striders

published May 6, 2020 seacoastonline.com, the York Weekly, Portsmouth Herald, Foster’s Daily and the York County Coast Star

The last time I wrote about water striders, it was the middle of the summer. I was sitting by a pond battling mosquitoes while watching them skate across the surface of the pond. I love how fast they move, which I didn’t understand. Are they skating and digging in their little feet for some purchase on the slick surface of the pond? Or is it a sticky surface that just looks like glass?

Water striders caught in the act of mating photo by Steve Morello stevemorello.com

Turns out not all small insects can do this – walk and skate on water. Water striders can because they have very fine hairs on the undersides of their legs that trap air and repel water. The scientific term for this is superhydrophobic. They can move so quickly because what they are doing is more like rowing, vigorously rowing, creating little swirls in the surface that help propel them forward. For their body size, they move fast, the equivalent of a 6-foot-tall person running 400 miles per hour!

I love the way their feet make little dimples in the surface of the water. Sometimes that’s how I first notice them – by the shadows those dimples cast on the bottom of the stream. As a biology teacher, I really love this, a textbook example of the high surface tension of water. They are bending the surface of the water.

I have been surprised to see water striders on my brook and along the edges of the river. I hadn’t realized they lived in flowing water as well as still water. Having never lived along a river until now, I have always made assumptions about who lives where. This was a big one. I always assumed they needed still-water, but there they were, skating upstream against the current, hanging out in the still water along the edges. And, as a wonderful sign of spring, this past weekend, while I was battling newly-hatched black flies instead of mosquitoes, I was able to catch some in the act of reproduction.

I realized these two were mating because they looked huge and on closer inspection it turned out I was seeing two, one being carried on the others’ back. So, I looked into water strider mating behavior. As you would expect, it is fascinating. As far as researchers know, there is no courtship involved. The male mounts the female. If she doesn’t fancy him, she might try to resist by deploying an extremely effective genital shield. However, the males have coevolved a behavior to prevent her from resisting, an extremely diabolical behavior. They coerce the female into mating by tapping out intricate patterns on the surface of the water. These patterns are meant to attract a predatory beetle that attacks from below the surface, the backswimmer. The female, since she is on the bottom, is more vulnerable to attack from below, so usually submits fairly quickly if the male starts tapping. This has been tested in an experiment (Han and Jablonski, “Male water striders attract predators to intimidate females into copulation,” Nature Communications, 2010) in which a small bar was glued to the back of the female. The bar raised the male up high enough that he couldn’t tap. When the male couldn’t tap, females resisted his advances for much longer periods of time.

I have been making more of a point than ever to get outside for some green time, to be in nature, to do some close and slow looking. By spending more time carefully observing water striders, my curiosity has been piqued and I have learned so much more than I would have with just casual observation. Look up slow looking. It’s something we shouldn’t have to be taught, but the art of sitting still in nature and observing what is going on around you is an art form, one that we can all participate in.

Frog and Salamander Egg Masses

published April 29 seacoastonline.com, The Portsmouth Herald, Foster’s Daily, the York Weekly and the York County Coast Star

Back in March, something wonderful happened. When nighttime temperatures hit the low 40′, when it was rainy and drizzly, huge numbers of amphibians began to move about, heading toward ponds to mate and lay eggs, most often to the vernal pools (temporary, fishless ponds) where they were hatched.

The two amphibians that participate in this annual early spring-late winter migration are wood frogs and spotted salamanders.

wood frog egg mass
Wood frog egg masses are loose clusters of eggs attached to a stick or branch at the surface. -Steve Morello photo

Wood frogs belong to a group of animals that have the remarkable ability to freeze but not die. To hibernate, they bury themselves in the ground and go into a deep hibernation in which their hearts stop beating, they stop breathing and partially freeze. Then with warm (above 40 degrees F) spring rains they revive, dig themselves out of the ground and head to the water to mate.

Spotted salamanders don’t carry things this far, but they do hibernate in underground burrows and tunnels, also emerging in the spring.

So, this magical thing happened (referred to as “Big Night” by wood frog and spotted salamander aficionados). These hardy amphibians came out of hibernation and headed to their ancestral pools to reproduce. Once they finished mating and laying eggs, they headed back to the woods to lead a very terrestrial existence for the rest of the year. Now, what remains in those pools are their egg masses.

So, now is a good time to check out your local vernal pools to see if you can find frog and salamander egg masses. The egg masses are big and have characteristic features that make it relatively easy to distinguish wood frog from spotted salamander eggs. Almost always the eggs are laid in vernal pools because, due to their temporary nature (vernal pools dry out in late summer and early fall), they are fishless. Fish would love to chow down on those huge egg masses. They are so easy to see.

Once you know what to look for, it is relatively easy to tell a spotted salamander egg mass from a wood frog egg mass; spotted salamander egg masses are surrounded by a jelly coat, wood frog egg masses are not.

If you were to pick up a spotted salamander egg mass (which you really shouldn’t), it would hold together and you would see that in addition to the gel surrounding each egg, there was a thick gel surrounding the entire mass.

If you were to pick up a wood frog egg mass (which you really shouldn’t), it would be looser and would fall apart more easily. The surface would look like a cluster of grapes. Each individual egg has its own gel-coat, but the entire mass lacks the extra protection of that outer layer.

Both wood frogs and spotted salamanders attach their eggs to vegetation (though sometimes spotted salamander eggs will rest on the bottom). Wood frog egg masses tend to be attached to overhanging vegetation or to twigs at the surface, whereas spotted salamander egg masses are attached to deeper branches, below the surface of the water. One interesting variation you might see with spotted salamander egg masses. Some have a clear gel-coat while the gel-coat of others is milky-white. The significance of this difference is unclear, but some research suggests it might confer some protection from predation.

Both wood frogs and spotted salamanders are considered to be obligate breeders in vernal pools, meaning they rely upon vernal pools for reproduction. The Seacoast area has an extremely high density of vernal pools, a habitat type threatened by suburban sprawl. If you know of a vernal pool in your area, try to protect it. These little amphibians have been using these pools long before we were here. They are also extremely important members of our forest ecosystems. They are food for an enormous number of predators – snakes, herons, raccoons, skunks and mink, to name a few.

To me, their migration to vernal pools to lay eggs is one of the most lovely of our signs of spring and each year. I seek those eggs out as a reminder of all the mysterious goings-on in my backyard.

Skunk Cabbage in Spring

skunk cabbage

Whenever I go into the woods this time of year, I look for spring wildflowers to be in bloom. There are a large variety of plants that take advantage of the scanty leaf canopy of early spring to grow and bloom quickly, before the trees leaf out. Where I live in North Berwick we are behind most of the Seacoast region in terms of blooms– my garlic is barely up yet, the ponds by the river still have some ice every morning!!!


In search of wildflowers, I went for a walk (by myself) at Great Works Regional Land Trust’s Rocky Hills Preserve last week and came upon one of the earliest wildflowers to bloom in New England-one of my favorite plants-skunk cabbage! This patch of skunk cabbage had been in bloom for awhile, I could tell this because in addition to the flowers the leaves were already out and gloriously unfolded into bright green skunky masses.

It is only after the flowers are pollinated and begin to wilt that the leaves unfurl-this is how I knew pollination was long over-those huge cabbage-like leaves. Early in the spring the skunk cabbage sends up a fleshy, highly-modified leaf forming that distinctive purplish hood. The scientific term for this is the spathe. Inside the spathe is a knoblike structure, a collection of tightly-packed flowers, called the spadix. Next time you see one, take a close look at the spadix. The structure of the spathe is really interesting–the petals emerging from a jigsaw puzzle-like surface that looks, to me, like the carapace of a turtle.

skunk cabbage spadix and spathe
Close up of spadix-this contains the flowers of the skunk cabbage-each of those little frilly bumps is a flower.


In the spring, often before the ground begins to thaw, cells in the spadix start to respire, breaking down starches stored in the root at an alarming rate. This rapid respiration produces heat! Studies have shown that respiration rates in thermogenic (heat-producing) plants such as skunk cabbage often equal those of mammals of similar sizes. The hood acts as an insulator, trapping the heat generated by the spadix, creating a balmy little microclimate (usually a fairly consistent 60- 70 degrees) that can melt the surrounding snow. I love Craig Holdredge’s (from the Nature Institute) description of the air currents generated by this warmth: “Due to the warmth production, a constant circulation of air in and out of the spathe occurs. From the flower head, warmth is generated and the air moves up and outward, while cooler air is drawn into the spathe. A vortex is formed with air streaming along the sculpted, curved surfaces of the spathe. In a habitat with numerous skunk cabbages, a microcosm of flowing warmth and odiferous air is created in which the first insects of spring fly.”


I have a large colony of false hellebore-a plant that looks somewhat similar to skunk cabbage and, as far as I know, inhabits the same kind of ecosystem–wet, marshy areas– growing along my river. I wish I also had skunk cabbage, and wonder why they don’t grow there as well. I have thought about trying to transplant some in, but it is usually a mistake to try to re-engineer an ecosystem. I worry that the skunk cabbage might take over-much as I love them I don’t want them to crowd out the false hellebore (another plant with an amazing back story). Skunk cabbages can form large colonies with extensive root systems that consist of a central rhizome that grows one or two feet into the ground with roots radiating out. The roots contract as they grow, pulling the plant down into the ground as it grows in the spring, keeping the stems and leaves at ground level. So the skunk cabbage, as a whole, grows downward every year, making it extremely difficult to remove. What’s more, these root systems and the colonies of skunk cabbage that erupt from them every spring can be hundreds to possibly thousands of years old!


If you can get outside, take a walk in the woods and look for spring wildflowers. We
are lucky enough to live in a place with 4 distinct seasons and are able to track the
passage of time by immersing ourselves in the highlights of each season (trailing
arbutus is flowering-a highlight, black flies are out in my neck of the woods–not a
highlight!). During this historic and stressful time it is more important than ever to get
some green time if at all possible.

Join the soft-shell clam recruitment network

published January 29, 2020 in The York Weekly, Portsmouth Herald and Foster’s Daily and online at seacoastonline.com titled ‘Nature News’

Clam recruitment boxes will be placed on clam flats in Wells Maine this spring Brian Beal photo

Dr. Brian Beal, Director of Research for the University of Maine at Machais Downeast Institute (DEI)-the easternmost marine research laboratory in the entire United States – gave a talk a week or so ago up in Wells about a research project that will start this spring all along the coast of Maine. The main focuses of the DEI all have to do with shellfish, primarily clams.

Brian was down in Wells explaining why large wooden boxes would be appearing on some clam flats in Maine, from Wells north to Sipayik, this spring and summer. The boxes are part of a study aimed at understanding how best to protect young soft-shell clams at a critical time in their development-when they are transiting from a water-born planktonic life to settling into the mud and sand flats and growing into delicious steamers. 

The clam recruitment boxes appear to provide a safe place for juvenile planktonic clams to settle Brian Beal Photo

Protecting soft shell clams from what? Primarily the invasive European green crab (Carcinus maenas).  Green crabs were introduced to New England back in the early 1800s by travelling in the ballast of ships carrying cargo from Europe to the United States.  Since then they have travelled up the East Coast, decimating the soft shell clam industry and have more recently (the late 1980s) reached the West Coast where they are wreaking similar havoc from San Francisco up to Seattle.  One reason green crabs are such a problem is that, unlike our native crabs, green crabs can swim out onto the mudflats to hunt. Our native rock and Jonah crabs don’t do this-they can’t swim and can’t get out and back to the mud flats as the tides ebb and flow..  Adult green crabs swim out to the mud flats at high tide, grab the soft-shell clam siphons (the fleshy clam ‘necks’), pull them out and eat them. Our soft-shell clams have adapted to this by digging deeper into the mud so that they can escape. However, a probably bigger problem is that young green crabs  (-perhaps a couple millimeters in size) also settle on the mudflats and prey upon anything smaller than themselves-juicy morsels like young soft-shell clams. 

To understand how the recruitment boxes work you have to know a little bit about a clam’s life cycle.  Before I joined the Wells Clam Conservation Commission almost a decade ago, I hadn’t understood how complex that life cycle is and how threatened it is by the invasive green crab. 

The life of a soft-shell clam (Mya arenaria) begins on a warm spring day when both male and female clams release their sperm and eggs into the water, if the two should meet-fertilization occurs.  This is called broadcast spawning and time is everything. The young that develop from this union are planktonic, they don’t look much like adult clams, instead they look like tiny blobs with tufts of fine cilia that they use to swim through the water.  These larval forms are called trocophore larvae that then mature into veliger larvae. The veligers look like a shell-less swimming clam. These baby clams come to intertidal flats via the water column. They swim for 2-3 weeks depending on seawater temperature and location along the coast, and then settle to the flats.  They are about the size of a grain of sand. This is when they are most vulnerable to predation. Here is where the recruitment boxes come in.  

Recently settled clams are at most danger from juvenile green crabs Brian Beal photos

Recruitment boxes are large wooden boxes with mesh on both the top and bottom.  Planktonic clams that settle into these boxes appear able to have much higher survival rates than those settling on the unprotected mud or sand flat.  

Mesh on both top and bottom of the boxes protects young clams from many predators Brian Beal photo

Why put out recruitment boxes? Soft-shell clam landings across Maine have declined by 45% since 2001, and few seem to be aware of this. An interesting tie-in with climate change appears to be that warmer sea surface temperatures (as we have been seeing in the Gulf of Maine) encourage explosive growth of green crabs.  Brian’s project aims to increase public awareness of what is occurring within this iconic fishery and create a statewide data set for fisheries managers in the Department of Marine Resources, and for other fisheries scientists, to better understand factors that affect the health and well-being of the soft-shell clam fishery.  

Whether you live in Maine or New Hampshire, if you want to get involved in this ‘recruitment network’ contact Brian at the Downeast Institute.  Dr Beal is looking forward to working with clammers, clam conservation committees, elected officials, schools and students in each community to learn about the early life-history of clams and what may be regulating or controlling their numbers.  Ultimately, he would like to create a network where the coastal communities that are part of this first trial are a subset of a larger group of communities all doing similar work that may play an important role in how soft-shell clams are managed.

Nature News: New England forests will have to evolve with climate

published January 15 2020 in the York Weekly, Foster’s Daily and the Portsmouth Herald and on seacoastonline.com

Dryad emerging from an old dead tree. Dryads protect and die with their trees. I wonder what they are thinking as our forests succumb to climate change-who do they go after? All of us who use fossil fuels?

This past weekend was unseasonably warm. Record-breaking in fact, for New England, with temperatures a good 7 or 8 degrees warmer than past records.

It seemed like everyone was out taking advantage of the balmy weather to take a walk in the woods. I headed up a side trail on Blue Job Mountain and while working my way up a slushy streambank looked across a clearing and saw something I had never seen before. There, in an old broken-off tree stump was a figure, made of wood, that looked to be climbing out of the tree.

The tree must have been felled relatively recently because the wood was still a bright orange-brown, a splash of color surrounded by the snow-covered pines and oaks. It looked raw and newly exposed. Sunlight hadn’t gotten to it yet (ultraviolet rays break down the cellulose in wood, bleaching out the color, giving it a silvery gray sheen). This figure that I, rationally, knew was just a random carving of the wood into human form, looked back at me. I knew it was just wood, but it still was magical. I could see how people from many different backgrounds, from all over the world, have believed that there are spirits that inhabit trees, so for a moment I believed a wood spirit was looking back at me.

Trees have lives that follow vastly different time scales from ours. They usually live much longer than we do and don’t move as we do. They are root-bound. They only move by reproducing, by sending their seeds out ahead of them into new territory. This warm weather was a reminder to me of their vulnerability. How is the rapid warming of our Earth going to affect the forests of New England?

A little over ten thousand years ago, the glaciers were receding and trees were re-colonizing New England. Slowly their seeds were carried or blown north and slowly they colonized the newly formed earth. This is a process called succession. When there is no dirt (as when glaciers had scoured all the dirt from the land), first lichens and mosses colonize bare rock, break into it and build soil. Then grasses and small plants move in, followed by shrubs, followed by fast-growing, light-loving trees, followed finally by the trees of a mature forest – the beech and maple, pine and oak of our temperate, deciduous forests.

Now, as conditions shift, as it warms, many of these trees need to move north or die. According to Mass Audubon’s “Effects of Climate Change on Woods & Forests,” a general rule of thumb is that “most tree species can colonize habitat beyond their existing range at a rate of 100 km in a 100 years (about 62 miles per 100 years). Some species will be able to move that fast, but warming temperatures will likely require forests to shift by 400 to 600 km (about 250 to 370 miles) by 2100, a rate faster than most species can tolerate.”

One of my favorite types of tree spirits are the Dryads. I first read about these as a child in the classic Bullfinch’s “Mythology.” According to Bullfinch, Dryads are nymphs or spirits, bound to particular trees, caretakers of the trees.

“Dryads or Hamadryads, were believed to perish with the trees which had been their abode and with which they had come into existence. It was therefore an impious act wantonly to destroy a tree.” I guess the caretaking days of my Dryad were over. Her tree had been felled by age or a wind storm. Perhaps that is why she was stepping out of the tree?

Susan Pike, a researcher and an environmental sciences and biology teacher at St. Thomas Aquinas High School, welcomes your ideas for future column topics. She may be reached at spike3116@gmail.com. Read more of her Nature News columns online.

Why do some trees get so tall?

published 12/31/2019 in the York Weekly, Foster’s Daily, the Portsmouth Herald and online on seacoastonline.com

I was just out visiting my son who lives on the coast of Northern California, the land of tall trees, the coast redwoods.  Coast redwoods (these are the state tree of California) are the tallest trees on Earth. I was thinking about our New England tall tree, the white pine (the state tree of Maine), and wondering whether they ever had a chance of growing as tall as the coast redwood.

Navarro River Redwood State Park near Mendocino California

There are a large number of factors that determine how and why a tree grows tall: genetics, environment, age.  The primary reason for a tree to grow as tall as it can is to beat surrounding trees to the sun. White pines and coast redwoods are great at this and will dominate a forest if they can get to the sun first.  White pines typically grow to about 150 feet tall (however pre-colonial white pines have been estimated to reach heights of at least 230 feet) while coast redwoods grow twice as tall-300 feet and taller (the tallest tree in the world is a 379 foot tall coast redwood named Hyperion).  How do they do it?

The two problems that have to be overcome to grow super tall are water and wind.  Coast redwoods tend to occupy sheltered valleys where they are protected from wind.  Like all trees they need to somehow distribute water to all parts of the tree. The long-held dogma of how this is accomplished is that groundwater enters the roots and is pulled upward through the tree by water evaporating from pores in the leaves.  Water is sticky, so as one water molecule evaporates from a pore in a leaf it pulls another water molecule up after it. The taller a tree grows the more difficult it is to get water up to the topmost leaves-gravity becomes a major drag. If those leaves can’t get enough water photosynthesis and growth start to slow.   

However this upward flow of water  isn’t the whole story. It turns out many trees can also absorb water into their leaves and move it downward towards the roots. There has to be water vapor in the atmosphere for this to be a useful adaptation.  Coast redwoods live in the fog belt, their needle-like leaves are almost constantly bathed in fog. Studies by the National Park Service found that some coast redwoods obtain 40% of their water from fog, not their roots!   And, according to a study on coast redwoods published in Functional Ecology (“Pushing the limits to tree height: could foliar water storage compensate for hydraulic constraints in Sequoia sempervirens?” published 2014 by H. Roaki et al) the pinnacle (topmost) leaves of the tallest growing coast redwoods stored water better than trees that didn’t grow as tall. So, tall-growing coast redwoods can take advantage of all that ambient water in the surrounding fog and both store and use it for growth.

Another factor in height is age-it takes time to acquire all of that biomass.  White pines easily live a couple hundred years-the oldest known specimens are over 400 years old.  Coast redwoods, on the other hand, are among the oldest living things on Earth-they can live for more than 2,000 years (the oldest living coast redwood is 2,200 years old).   Hyperion, the tallest tree on Earth, a baby by coast redwood standards at somewhere between 600 and 800 years old has still had a remarkably long life.

Redwood stumps provide nutrients for new growth. Here some sorrel grows at the base of a stump

So, while our East Coast white pines probably couldn’t ever grow as tall as coast redwoods, -conditions and adaptations aren’t quite right-one similarity between these two species is how it feels to walk into a white pine or a coast redwood forest.  There is a cathedral like quality to these forests, they are quiet and dark. The filtered sunlight adds to their majesty, illuminating the mist in much the same way that light falls through the stained glass of a human-made cathedral and illuminates the dust motes floating through the air.   These forests we walk through today are largely young trees. Just imagine the grandeur of a pre-colonial forest, fully mature white pines or coast redwoods reaching towards the stars.

Chickadee-dee-dees!

published Dec 25, 2019 the York Weekly, Portsmouth Herald, Foster’s Daily and seacoastonline.com

I think if you ask any New Englander to name the top three birds at their feeder, the chickadee would be on everyone’s list. I also think that of any of the common bird calls in our forest, the chickadee’s is the one most of us could easily identify. These tiny, round birds with a black cap and bib that contrasts with its white cheeks are found all over the northern parts of the United States and up into the middle of Canada.

black-capped chickadee

When not living in the suburbs you can find them in deciduous and mixed forest, almost any kind of open woodlands, as well as thickets. When we clear forests for agriculture or development, we are increasing the amount of forest edge – a habitat type that chickadees love (unlike something like an ovenbird that requires deep woods for nesting).

The black-capped chickadee (Poecile atricapillus) is one of seven species of chickadees found in the United States. They all have similar body shapes with sometimes subtle differences in color or streaking on their heads. For example, the boreal chickadee (the other New England chickadee) has a brown cap and cinnamon flanks and a more northerly range, preferring the boreal forests of Canada and the mountains of New England.

Chickadees probably do so well with humans due to their flexibility and curiosity. They are highly social birds that are quick to explore new environments and take advantage of resources (they will usually be the first bird to use a new feeder). According to the Cornell Lab of Ornithology, one study found that “every autumn black-capped chickadees allow brain neurons containing old information to die, replacing them with new neurons so they can adapt to changes in their social flocks and environment even with their tiny brains.” They really do have tiny brains, which makes their ability to memorize that much more remarkable. They often hide food for later use and can remember thousands of hiding places!

Try listening to their calls. They actually have a very complex language, much more than the obvious chickadee-dee-dee. They can communicate information about other flocks, predators and foraging information. For example, they add ”-dees” to their chickadee call to indicate higher threat levels.

From the number that show up at my feeder every day one, wouldn’t know that we are in the middle of a mass extinction of birds. A recent Science Magazine article recently reported that there has been a 29% decline in birds in the United States over the past 50 years (that’s almost 3 billion fewer birds on the North American continent today compared to 1970!). While chickadees aren’t considered endangered, or even threatened at this point, their distribution is expected to shift and their numbers decline due to ongoing climate change. A 2017 report by Massachusetts Audubon predicted that by 2050 the black-capped chickadee population is likely to disappear from coastal areas of Massachusetts and decline substantially throughout southern New England as rising temperatures push their range to the north.

For now, if you want to attract chickadees to your backyard, provide feeders (they are one of the easiest birds to attract to a feeder), black-oil sunflower seeds and suet will do the trick, and some standing dead trees for cavity nesting sites (they also like nest boxes).

While chickadees are around all year, I think of them as winter birds. Watching them at my feeder as snow lightly falls is a wonderful way to welcome winter in New England.

Susan Pike, a researcher and an environmental sciences and biology teacher at St. Thomas Aquinas High School, welcomes your ideas for future column topics. She may be reached at spike3116@gmail.com. Read more of her Nature News columns online.