The sub-nivean zone

Hi all! Happy New Year! I wish everyone joy, peace, and health in the upcoming year.

 

And now, to start things off with a bang, check out my most recent Earth Matters column in the Hampshire Gazette (Jan 2, 2016). It’s about life under the snow:

 

http://www.gazettenet.com/news/townbytown/amherst/20162762-95/earth-matters-the-sub-nivean-zone-life-under-the-snow

The Pond in Winter

Wow, what a warm winter it’s been! Although today is predicted for a high of 37 (F), as those of you who live in this area know, the temperature has been in the 50s for weeks – very warm for December in New England. Christmas is nearly upon us, but the lack of seasonally-appropriate weather seems to have robbed almost everyone I know of a sense of “Christmas spirit”. (At least, amongst those who celebrate Christmas.)

On the up side, the warmer weather means I have gotten to go outdoors at lunchtime and take photographs! I am by no means a professional photographer, but I’ve been experimenting with a loaner camera.  Not surprisingly, wildlife photos are proving to be very difficult (the lag time causes me to “lose” the subject, and focus can be a challenge), but here are some early efforts.

 

Mallard 121315
Male Mallard 12/14/15
Canada Goose 201415
Canada Goose 12/14/15
Black Ducks 121615
American Black Ducks 12/14/15

We also had this unexpected visitor: a red-necked grebe in winter plumage. It is unusual to see this bird on such a small body of water. It was a bit shy and stayed in the middle of the pond.

121415 red-necked grebe Umass Amherst pond copy
Red-necked Grebe 12/14/15

Photos aside, this warmer weather does not signify anything good about the condition of our planet. Here’s to colder temperatures in the days to come!

Fall bird migration

By Martin (originally posted to Flickr as 041006) [CC BY-SA 2.0 (http://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons
By Martin (originally posted to Flickr as 041006) [CC BY-SA 2.0 (http://creativecommons.org/licenses/by-sa/2.0)%5D, via Wikimedia Commons
A couple of days ago I re-read Mary Oliver’s famous poem, Wild Geese, a lovely piece which got me thinking about bird migration. This semester I have been taking a fall birding class through the Hitchcock Center with Scott Surner, from the Hampshire Bird Club. We have been focusing on fall plumages; though I had previously considered myself to be a reasonably decent birder, I now realize that my skills are not nearly as good as I had thought!

The old Peterson’s Field Guide page entitled “Confusing Fall Warblers” is only  the tip of the iceberg; trying to identify the fall and winter plumages of not only warblers but shorebirds and many others is like starting all over again, without the benefit of song to help with the id. I have had to buy a new field guide as, alas, my old Peterson’s is not quite up to the task. Now I am on to National Geographic Field Guide to the Birds of Eastern North America, which is serving me much better this season.

In an effort to improve my learning, I have also done a few pencil drawings of various birds; they are just copies of what’s in the book, but they are definitely improving my memory for the next time I see a flash of movement or color through the trees. Maybe I will post some of this work after my artistry improves.

If you are interested in fall migration and want to know what is coming through your area when, check out the Cornell Lab of Ornithology’s Regional Migration Forecast; this week’s post includes a terrific close-up of a loon with a beady red eye: http://birdcast.info/forecast/regional-migration-forecast-2-9-october-2015/.

Connecticut River Valley watershed

Bartons Cove plunge pools

Check out my new article in the local paper on the Connecticut River Valley watershed!

It explains what a watershed is, provides some geological and historical details about the this region in particular, and links to the Connecticut River Watershed Council’s Source-to-Sea cleanup. Here’s a preview of the article:

If you’re like I was a few years ago, you may be wondering, “What is a watershed, anyway?”

In fact, the word “shed” is quite descriptive of this geographic phenomenon. Much like rain cascading down one side or another from a shed’s roof, a watershed can be thought of as a geographic area defined by ridges of high ground that determine which direction water travels en route to a major basin, river or ocean.

A large watershed can encompass many smaller watersheds. For instance, the largest watershed on any given continent is defined by the continental divide. In North America, the continental divide runs along the crest of the Rocky Mountains. Broadly speaking, rivers to the west of the Rocky Mountains flow to the Pacific Ocean, and rivers to the east flow to the Gulf of Mexico or the Atlantic Ocean.

Of course, within these enormous watersheds are many smaller regional and local watersheds. The dominant regional watershed in our area is the Connecticut River Valley, whose drainage basin encompasses five states, one Canadian province and 11,260 square miles.

Approximately 410 miles long and passing through New Hampshire, Vermont, Massachusetts and Connecticut, the Connecticut is the longest river in New England. It starts at a small pond known as the Fourth Connecticut Lake…

If you are interested in improving the Connecticut River’s water quality, see here for details and updates on this year’s Source-to-Sea cleanup. (As of last year, the cleanup project had removed almost 900 TONS of trash from the watershed over the last 18 years!) It’s not too late to jump in – the cleanup runs through the end of the day today!  See you there!

Emerald Ash Borer

"EmeraldAshBorerdorsal" by USDA-APHIS - http://www.hungrypests.com/img/the-threat/emerald-ash-borer/small/EmeraldAshBorer6.jpg. Licensed under Public Domain via Commons - https://commons.wikimedia.org/wiki/File:EmeraldAshBorerdorsal.jpg#/media/File:EmeraldAshBorerdorsal.jpg
“EmeraldAshBorerdorsal” by USDA-APHIS – http://www.hungrypests.com/img/the-threat/emerald-ash-borer/small/EmeraldAshBorer6.jpg. Licensed under Public Domain via Commons – https://commons.wikimedia.org/wiki/File:EmeraldAshBorerdorsal.jpg#/media/File:EmeraldAshBorerdorsal.jpg

Alas, it has been a long time since I’ve update this blog! Work and a host of other time-occupiers pulled me away for a while, but now it’s mid-summer and I’m back! The trees are fully leafed out, the chickadee are losing the fight with the squirrels for the birdfeeder, and the foxes in the neighbors’ wood lot bark back and forth to each other in the middle of the night for reasons known only to themselves.

In other news, I’ve written an article in the local paper on the Emerald Ash Borer – check it out:

What’s tiny, shiny and destroys fully-grown ash trees as well as any fire-breathing dragon?

Yes, it’s the emerald ash borer, that infamous pest from Asia, whose larval feeding tunnels can girdle the inner bark of an ash tree, cutting off its supply of nutrients and water and eventually starving the tree to death.

The adult emerald ash borer (EAB), as its name suggests, is a bright, iridescent green beetle, about ⅓ inch long. It has a coppery-red upper abdomen that is often hidden under its wings.

Although the adult EAB does chew on the leaves of ash trees, this is not the primary source of trouble. Rather, the female EAB, which lives for about six weeks, can lay anywhere from 40 to 200 eggs in the tree’s bark. Fertilized eggs hatch about two weeks later, after which the larvae chew tunnels through the outer bark and into the inner bark. This is the real source of trouble for the tree because those serpentine tunnels ….”

To continue reading, follow this link:

http://www.gazettenet.com/news/specialcoverage/goinggreen/17352255-95/tiny-green-dragon-threatens-our-forests

Happy Fourth of July weekend to you all!

Reeve

Owls in February

In recent days, we have been the ever-so-lucky recipients of an “arctic blast”, exceptionally cold air pulled down by the jetstream from more northern climes. The wind chill has been much worse than the actual temperature; it was supposed to be -31 a couple of nights ago. I personally did not confirm this, preferring to stay inside and watch another episode of “Bones”.

By William H. Majoros via Wikimedia Commons
By William H. Majoros via Wikimedia Commons

On the upside, in spite of the cold weather, nature presses on. Believe it or not, now is this time (in New England, anyway) when great horned owls should be nesting, skunks mating, and redpolls arriving from their southern homes. If the weather warms up tonight (which is predicted), I might go out walking through the snow, listening for great horned owls. This is what I will be listening for:

http://www.allaboutbirds.org/guide/Great_Horned_Owl/sounds

Of course, great horned owls aren’t the only owls you might hear at night. Cornell’s Ornithology Lab offers a download of a variety of owl calls that you might encounter.

http://dl.allaboutbirds.org/owlsounddownload?utm_referrer=http%3A%2F%2Fcams.allaboutbirds.org%2Fchannel%2F46%2FGreat_Horned_Owls%2F

And, for the real bird dorks among us (like me), here’s their livecam of a great horned owl’s nest in Savannah, Georgia. This is what we in New England have to look forward to in the upcoming months!

The nest, originally built by a pair of bald eagles, now contains the female and two baby owlets, hatched in early February. For video highlights dating back to mid-December, see here: http://cams.allaboutbirds.org/channel/46/Great_Horned_Owls/

Happy owling!

Snow, snow, and more snow

"Novo mesto Breg 2". Licensed under CC BY-SA 3.0 via Wikimedia Commons
“Novo mesto Breg 2”. Licensed under CC BY-SA 3.0 via Wikimedia Commons

I am perhaps growing a little weary of the subject of snow, yet that is what there is this winter, in vast and ever increasing abundance. Snow, snow, and more snow. Lacking snow shoes, I wade through thigh-deep powder to the bird feeder, trying to keep up with the demands of little goldfinches, chickadees, and nuthatches. I sprinkle sunflower seeds under the feeder for the ground-feeding birds, knowing that, in fairly short order, those seeds will be covered up by yet more snow. I wonder how many of them get eaten, either from above by birds and squirrels, or from below by small rodents tunneling up from the sub-nivean world. Come spring, will I find a giant pile of soggy, uneaten seeds attempting to sprout? Several more months will pass before I’ll have an answer to that question.

In the meantime, some youthful part of me still gets excited by snow days. “What?? Snow day?? Everything’s closed!! No school!!” It’s been a while since I’ve been in school, but the excitement persists. In light of that feeling, here is fun poem by Billy Collins, entitled “Snow Day”.  Enjoy!

http://www.poetryfoundation.org/poem/176051

The sub-nivean zone

Well, the great blizzard of Ought Fifteen was a bit of an anti-climax here in my neck of the woods. Instead of the 27″-33″ that had been predicted, we got about 5″. I’m not complaining – the poor folks in Nantucket and Boston really got hammered – but rather am admitting to a mild feeling of let-down after all the water I bottled, the extra wood we sawed, and the emergency flashlights and candles I purchased. Ah well, at least we have another 5″ of snow, and, counter-intuitively, that actually makes for better winter conditions for our small wildlife friends, including moles, mice, voles (and their predators), various insects, and an assortment of bacteria and other microscopic life. This is because of the creation of the sub-nivean zone, which occurs after about 8″ of snow accumulation. (In case you are doing mental math, we had 3″ or 4″inches of previous snowfall, plus the additional 5″ish, leading to a total of 8″ or 9″.)

Entrance hole to the sub-nivean world. Photo by the Seney Natural History Association via Wikimedia Commons.
Entrance hole to the sub-nivean world. Photo by the Seney Natural History Association via Wikimedia Commons.

The sub-nivean zone (“sub”= under, “nivea” = snow) occurs in a protected area between the upper-level snow pack and the earth’s surface, where the temperature hovers around 32 degrees (F). The upper levels of snow provide insulation, while the lowest level melts slightly due to the heat from the earth’s surface, providing water and unfrozen food sources. Indeed, a whole winter ecosystem exists here, a fact that was not widely known until relatively recently. Rodents living in this zone create tunnels, air holes, latrines, and nesting areas, feeding on grasses, insect eggs, and whatever else they can find during the winter months.

The upper layers of snow hide rodents from the sight of predators, although owls can hear them running from 30 yards away, and foxes and coyotes can smell them. These predators will pounce through the snow, attempting to catch their prey with claws or mouth. You have no doubt seen videos such as this one, of a fox leaping into the air to try to pin a rodent through the snow:

(As a side note, according to the Discovery Channel, new research shows that if a fox is facing north (at least in North America), he/she is 75% more likely to be successful in catching prey through the snow than if facing any other direction. The reason for this is not fully understood.)

Weasels, more sneakily, slide down the rodents’ air tunnels and chase their victims through their own homes. (Don’t feel too bad for the little critters, though; if it weren’t for predators like weasels, our world would shortly be overrun with mice, voles, and other rodents, given how fast they tend to breed.)

Next time you are out walking in deepish snow, keep an eye out for traces of predators, such as fox jumps or owl/hawk punches. (In the photo below, note the marks left by the wing feathers and the hole punched through the snow by the bird’s feet.

bird wing snow
Photo by U.S. Fish and Wildlife Service via Wikimedia Commons: https://commons.wikimedia.org/wiki/File:Snow_angel_%2811585439005%29.jpg

Alternatively, look near the base of trees or rocks for air holes leading to the sub-nivean world. (Please don’t disturb the holes, however; the creatures that made them have enough to contend with without our interference.)

For more information on the sub-nivean zone, see here:

http://www.burlingtonfreepress.com/story/news/local/2014/12/26/subnivean-zone-shelter-snow/20901281/

or here:

http://mag.audubon.org/articles/nature/life-under-snow.

Seed Catalogs

‘Tis the time of year for seed catalogs. In my opinion, seed catalogs are like the cocaine of gardening world – sheer escapist fantasy in which one has infinite time, energy, and garden space, a world in which weeds, pests, diseases, and aching backs do not exist. In the world of seed catalogs, each variety is better than the next. Take, for instance, the choices of basil in Fedco’s catalog:

"Basil leaves" by Paul Goyette. Licensed under CC BY-SA 2.0 via Wikimedia Commons
“Basil leaves” by Paul Goyette. Licensed under CC BY-SA 2.0 via Wikimedia Commons.

Genovese Basil (70 days) The choice of many connoisseurs for making pesto.  (Ah ha! Well, if it’s the choice of connoisseurs, this is clearly the right type of basil.) Also called Perfumed Basil. (Oh good. I love the smell of basil. But wait, what’s this?…)

Anise Basil Originally from Persia. (Persia?? Oh, exotic!! Bellydancing. Wild animals. Lawrence of Arabia. This must be good.) Vigorous mulberry-tinted basil with anise fragrance makes highly decorative tall bushy plant. (Anise!? Yum. Pretty AND smells good AND exotic.) Slow to bolt. (Excellent. Because bolted basil is bad basil.) Great in Italian tomato sauces. (Perfect!) Also used in Thai and various Mediterranean cuisines. (Excellent! I can use it for everything. This is clearly the right kind of basil! But wait….)

Sacred Basil OG Ocimum tenuiflorum (100 days) Native to India and used in Indian as well as Thai cuisine. (Sacred basil! Wow, what does that mean?) Spicier than other basils and quicker to go to seed, but still usable when covered with purple flowers. (Hmm.) Used in Ayurvedic medicine as a poultice on acne, ringworm, eczema and insect bites. (Whoa! Ok, I don’t have acne, ringwork, or eczema. I’m sure I’ll have insect bites, though.)  Strengthens the immune system and increases oxygen uptake in the brain. (Well, I could definitely use more oxygen in the brain.) Stands a bit more cold than other basils. (Excellent! Because it’s cold around here.) OT-certified. (Whatever that means.) (Sacred basil! I read somewhere that Indians put in their window sills to ward off evil. Millions of Indians can’t be wrong! I have to get this one. But wait. I meant to get some lemon basil and some Thai basil…)

"Thai basil with flowers" by Risacher. Licensed under CC BY-SA 3.0 via Wikimedia Commons
“Thai basil with flowers” by Risacher. Licensed under CC BY-SA 3.0 via Wikimedia Commons.

And so it goes. And this is just basil!! I haven’t even gotten to the tomatoes, or the carrots or the green beans. I’d better not open the corn section, since I don’t have enough room for corn. A few sunflowers would be nice, though….

Winter survival

Hi all! Great to be back after a little hiatus.

Given the weirdly fluctuating outdoor temperatures so far this year, I have been contemplating the myriad of ways in which animals survive the winter. In pursuit of more knowledge, I pulled Bernd Heinrich’s Winter World: The Ingenuity of Animal Survival off of the shelf, and, even though I am only a couple of chapters into it so far, have already learned several interesting tidbits.

Snow fleas (Hypogastrura nivicolautilize) utilize anti-freeze to stay alive in the snow. Photo by Daniel Tompkins via Wikimedia Commons
Snow fleas (Hypogastrura nivicolautilize) utilize anti-freeze to stay alive in the snow. Photo by Daniel Tompkins via Wikimedia Commons.

For instance, some insects survive winter because their bodies contain substances, similar to antifreeze, that lower the freezing point of water. (As a side note, some types of deep water fish contain a similar type of “antifreeze”, the gene for which is now being used to prevent ice cream from getting freezer burn. Yoiks!)

Even more astonishing than having antifreeze-filled bodies is the fact that some insects have the ability to separate the freezing and melting points of water (!!) in a process called “thermal hysteresis”. Think about that for a minute: generally, the temperature at which water goes from a solid state (ice) to a liquid state (water) is 0 degrees Celsius/32 degrees Fahrenheit. However, the process of thermal hysteresis allows these insects to exist in a “supercooled” state (below 0 degrees C but without freezing) and thus survive cold winter temperatures without dying. This supercooled state, however, is highly unstable, and the introduction of any foreign molecule will cause the entire system to break down and freeze almost instantly. Life is so amazing, and so fragile!

Additionally, some insects can utilize a process called “diapause”, which could be loosely defined as a type of “arrested development”. Many moths, for instance, live as pupae through the winter in a diapausal state.  (A common example is the type of yellowish, fuzzy tent caterpillar cocoon that you sometimes find attached to the underside of a log in a woodpile.

by NobbiP via Wikimedia Commons
A woodpile is a great place to look for overwintering insects. Photo by NobbiP via Wikimedia Commons.

These pupae, which are waiting until spring to hatch into moths, are in a state of diapause. (Naturalist’s note: not all fuzzy, pale-colored cocoons are those of tent caterpillars; you may need to do further research if you wish to correctly identify any particular species.)

The phenomenon of diapause is not limited to winter months, however; some adult insects will enter a reproductive diapausal state in the summer when migrating or searching for host plants. In fact, some types of insects, in the adult phase, do not even have mouth parts, as they quickly breed and lay eggs before dying without eating anything at all. I am not sure if this evolutionary phenomenon counts as diapause or not; perhaps biologists refer to it as something else altogether.

By Stephen Lody via Wikimedia Commons
Adult polyphemous moths (Antheraea polyphemous) have only vestigal mouthparts. Photo by Stephen Lody via Wikimedia Commons.

Anyway, the next time you are outside this winter, check under logs, rocks, or dead leaves to see what kinds of insect life you can find, waiting until next spring to re-emerge. If you want to learn more about what kinds of creatures you are likely to discover, see here for what one biologist found in her woodpile in Ontario. (Note that the author of that blog is also a co-author of the new edition of the Peterson Field Guide to Moths of Northeastern North America Happy exploring!