Monday, March 31, 2014

Peeper keeper

Peep. Peep. Peep.

Choruses of spring peepers have risen from the woods. But how did those inch-long amphibians deal with the vagaries of New England weather that can swing temperatures from the 70s to the 20s in April?

To peepers, a sudden freeze or even a spring snowstorm is no sweat. Cold air triggers the frog's liver to create glucose. Blood brings this antifreeze to the vital organs like the brain and heart, keeping them from freezing. But the rest of its body — more than 60% of it — can freeze for weeks without harming the frog.

So on a walk in a wood on a cold spring day, you may find a small, frozen frog. If you put it in your warm hand, the iced peeper will simply melt and hop away, no doubt with a song in its heart.

Wednesday, March 26, 2014

Sour Swamps

As winter thaws out of the ground and opens the waters of our swamps, a characteristic sour scent appears. It tickles our noses with a strong smell that is far from perfume, but still has a strange attraction. 
 

We are probably smelling a soup of scents.  

Anaerobic bacteria, the kind that thrive in water and soil with little or no oxygen, give off hydrogen sulfide and phosphine gases as they feed on the products of decomposing leaves, grasses and other vegetation from the previous seasons’ plants. Those gases combine with others offered by freshly thawed, but decaying vegetation. Add to the mix the malodorous Skunk Cabbage, and you have a special blend of wetland aromas that can be found only in early spring. 
 

This pungent and pleasant scent signals renewal in these hotbeds of life. Swamps are where the new season really begins, a nursery full of not only stinky bacteria, but countless aquatic and land insects, small fish, amphibians, reptiles, mollusks, as well as wildflowers, that serve as food for other wildlife emerging from dens or arriving by wing. 
 

And so, though it arises from death, this sour scent is really a sign of life.

Sunday, March 23, 2014

Size and color vs. cold and hot

Do birds of the same species look alike throughout their ranges?
 

You might think that a species, by definition, would look the same wherever it was, but in fact most non-migratory birds differ within their ranges. 

Hairy Woodpeckers are bigger
in the northern part of their
range than they are in
the southern part.
Birds of a wide-range species that live in the cold end of the range tend to be bigger than birds that live in the warm end. A Hairy Woodpecker from Central America is noticeably smaller than a Hairy Woodpecker from Canada. 

Larger birds tend to be able to conserve heat better than smaller ones. Over many generations smaller birds born in cold regions have been more likely to die from mid-winter cold, leaving the larger siblings to carry on the species.
 

The process of size variation doesn’t take all that long, either. The House Finches, introduced into North America in the mid-1800s, have already developed smaller versions in the southern United States than are found in northern states and Canada.
 

The tendency of a species in cold climates to be larger than its fellow members in warm climates applies not only to birds, but all warm-blooded animals. In fact, it is a scientific principle is called Bergmann’s Rule, named for 19th Century German biologist Carl Bergmann, who developed it.
 

A similar principle is called Allen’s Rule, which says that cold-region birds have shorter wings, beaks and legs than those in the warm regions – all techniques, again to conserve heat.
 

Gloger’s Rule is not about size, but color. In 1833, Wilhelm Gloger, a German naturalist, postulated that, due to the intensity of the sun, warm-blooded members of the same species living in warmer climates tend to be darker than those in colder climates. It works for humans and other animals including birds. Birds of a single species that ranges from cold to hot will have deeper feather colors in the south than in the north.

Friday, March 21, 2014

Murmurations of starlings

Starlings are weed birds, right?

Well, certainly they are not natives, they are not colorful, and they are usually not much noticed.


But starlings perform one of the most amazing shows in nature.

It’s called a “murmuration.”

Rather than spend a lot of words explaining this astonishing phenomenon, I recommend this video.

Keep in mind that while, in our own murmurations, we may not have as many birds as are depicted in the video, smaller shows like this can be seen wherever there are starlings gathered before and after breeding season.  And that’s pretty much anywhere in North America during most of the year.

Wednesday, March 19, 2014

Ranges big and small

The dwelling ranges of birds can vary from tiny to global.

The 50 small Galapagos Islands about 600 miles off the coast of Ecuador are home to two-dozen species of birds found nowhere else on Earth.

In the United States, the Everglades Kite is found only in certain parts of southwestern Florida. The summer range of the Kirtland’s Warbler is limited to young Jack Pine forests of Michigan, found in an area only about 60 by 100 miles at the top of the Lower Peninsula. This warbler winters in the Bahamas.

The Osprey can be found
on every continent.
Both birds are classified as endangered species, which is not surprising, given the limited ranges in which they live.

Some species span the globe.

Many like the Herring Gull are circumpolar, a term that means a bird can be found around the world on one side of the equator or the other. A few species, such as the Osprey and Short-eared Owl, can be found on every continent.

Among migrating species, the summer and winter ranges can be astonishingly far apart. The American Golden-Plover spends its summer on the north shores of Alaska and Canada and its winters in Argentina and Paraguay.

Monday, March 17, 2014

What is the 'range' of a bird?

What does “range” mean when talking about a species of bird?

The range of a bird species is the territory in which one would expect to find it living at one time of the year or another. Ranges vary from small areas of less than the size of Rhode Island to nearly the entire world.

Several factors determine a species’ range, chief among them the climate and the kind of soil. Climate and soil affect the kind of vegetation that grows, and vegetation is the source of food, nesting sites and materials, and protection for most birds. Few birds can survive in the desert, where vegetation is spare, but some have adapted to it. Other birds require the sea, or at least lakes or rivers, for their survival.

Various factors also limit range. Oceans are the most obvious; few birds are capable of crossing an ocean under normal conditions. Temperature limits range; few birds can survive an Arctic or Antarctic winter, for instance. High mountains define some range boundaries -- many species are found either east or west of the Rockies.


The Red Knot can be seen in 
Connecticut, but Connecticut is not 
part of the Red Knot's range.
Many birds migrate and their territory includes a “summer” or “breeding” range and a winter range. Often the summer and winter ranges overlap so that a species might live year round in some states or provinces while in other regions, the birds appear only in summer or winter. In the case of such species as the Tundra Swan and the Snow Goose, summer and winter ranges are widely separated.

Although during migration these birds fly over a lot of land and may stop for a bite to eat on the way to and from ranges, the territory in between the winter and summer grounds is not considered part of its range.  For example, the Red Knot has a winter range at the southern tip of South America and a summer range in the northern Arctic. While it can be seen on Connecticut shores in March, Connecticut is just a brief stopover on its long way north and not part of its range.

Friday, March 14, 2014

Free as a bird?

People use the phrase “free as a bird,” but are birds really free?

“Free” is one of those words that mean different things to different people. Americans live in the land of the free, but if they fail to pay their income taxes, they may wind up as jailbirds. Despite being free, we have obligations and even a hobo has the obligations to feed and shelter himself.

Birds, too, have obligations. Foremost is survival. To survive they must feed themselves.

A very free bird?
Since most birds have evolved into feeding on certain kinds of foods, they must live near the sources of that food. Thus, a Sanderling, which lives solely on seashore creatures, is not about to take off from an ocean beach and head for a vacation on the Kansas plains.

Many birds migrate, sometimes thousands of miles, to find food and nesting grounds. Other birds are homebodies, sticking to the same small neighborhoods all over their lives. They are free to choose where to feed and where to nest, but only within restrictions of terrain and location.

Some birds might be said to be “freer” than others. The American Crow and many species of gull are remarkably flexible in the kinds of foods they eat and the territories they inhabit. You will find crows at the edge of the ocean and deep in the desert, in the near tropics and the frozen north, in backyards and thick forests. Some crows migrate, some don’t. And judging from the refrigerator leftovers I’ve seen them eat, they may be the ultimate omnivore.

The sight of a bird in flight feeds the imagination and no doubt inspired someone to concoct the phrase, “free as a bird.”  But birds are mostly bound by both need and instinct to dwell in certain places and follow certain patterns of living.

Humans, who can hop in a car, or board a plane or boat, and travel anywhere in the world, would be the envy of any bird — even the ubiquitous crow — that might have an urge to be free.

Wednesday, March 12, 2014

Woodcock woes

Each March, nature centers and Audubon groups sponsor “woodcock walks,” as much a part of the tradition of spring as spotting robins in the yard or Red-wing Blackbirds in the swamps.

The American Woodcock is famous for its mating maneuvers. In his Essential Field Guide Companion, Peter Dunne describes it concisely: “Aerial courtship display is arresting and easily observed at dawn and dusk. Birds spiral aloft, calling as they climb, then descend rapidly to earth like broken kites. After an interval, the display is repeated.”

Late snow can be deadly for 'timberdoodles'
What also makes woodcock fascinating is that they are actually shorebirds – members of the Sandpiper family – that eons ago moved inland and inhabit forests and fields instead of beaches and dunes. Their main food is earthworms.

It is a pudgy bird whose neckless head appears to be what Dunne calls “a bump on the body.” He says that the overall effect of the bird is like viewing a “meatloaf on a stick.”

They have endeared themselves to countless generations of farmers and nature-lovers, who often call them “timberdoodles.”

The American Woodcock has been somewhat in decline in Connecticut, probably because of habitat loss. But in March, late winter storms can also take their toll.  In 2007, there was a big St. Patrick’s Day storm, and many reports of dying woodcock. 

For instance, George Rieger of Greenwich told us, “The morning after the recent ice/snow storm we found a woodcock outside of our front door near Bruce Park in Greenwich. The bird appeared healthy but was weak and unable to fly.

“We put it in a box with torn up newspaper and some water. We tried to keep the bird warm but not too warm. After 24 hours the bird was strong enough to escape the box and flutter about.”

He took them to a nearby sanctuary.

“Three birders were at the sanctuary. They suggested that we let the bird try to make it. I was skeptical. Two of the men took the bird to a tree and released it. I said to my wife and the third man that the woodcock was bait for predators.

“No sooner had I spoken than I saw a black shape flying toward the woodcock. I yelled ‘crow.’ The youngest of the two men sprinted toward the woodcock and arrived just in time to dislodge it from the crow's beak.

“We left the beautiful woodcock with the birders whom I am certain did the best that they could for the bird.”

They may have taken it to Meredith Sampson, director of Wild Winds Inc., and a wildlife rehabilitator in Old Greenwich. She had gotten many woodcocks that season.

Meredith reported on the Connecticut Birds internet discussion group, “Received the eighth woodcock for rehab. Sad to report the bird expired about a half hour later. It was extremely emaciated at 101 grams and apparently crashed into something which resulted in a misaligned beak and severe eye injury. Found in downtown Stamford.

“Out of the eight woodcocks in rehab, two have survived and were released three evenings ago. All came in severely emaciated, weights averaging around 90-100 grams.

“It's rare that I get in this species – I don't even get one a year! It’s heartbreaking to see this happening.”

What was happening? Milan Bull of Connecticut Audubon offered an answer on Connecticut Birds.

“Woodcock are apparently dying in considerable numbers across the Northeast this spring due to a crusted snow pack isolating these early migrants from the soil and earthworms below. We have had calls throughout Connecticut from members and wildlife rehabilitators reporting dead and emaciated woodcock in numbers I haven't seen in similar past events, and those are only the ones that are discovered!

“This is not a good sign, considering woodcock are on a long-term decline as it is.”

Fortunately, soon after, warm weather arrived and melted the hard-topped snow, giving the surviving woodcock access to their worms. 

And fortunately, our hard and thick pack this year has been steadily melting and in many places, has disappeared.

Tuesday, March 11, 2014

Flowers, finally!

The first flowers of a new season are always a joy to behold, especially after a long, cold and snowy winter. Crocuses in our yard this afternoon.

Monday, March 10, 2014

Wings and water

Early March is when many water-loving birds return to the Northeast: Red-winged Blackbirds, Kingfishers, and several kinds of ducks, for instance. Swamps, streams, shorelines and ponds are a draw for the first migrants because they offer food from the earliest bits of new life as well as from some leftovers of old life.

As soon as the ice and snow begin to thaw, insects such as carrion-eating flies start to appear in the air and others emerge in the water. Fish, once protected by ice, become exposed, and amphibians like salamanders and spring peepers crawl out of their winter beds. Plants that like wet feet become accessible in the water and begin to grow in the swamps.

Wetlands also offer treats left from last season in the form of berries and seeds still held by plants like buttonbush. The bush’s aged but still tasty fruits are designed to attract the hungry migrants. The birds eat and soon “plant” the seeds, complete with fertilizer, far from the mother bush and just in time for a new growing season.

Sunday, March 09, 2014

Saving daylight?

From an old campaign to make Daylight Saving Time the law in the United States.
Hardly a household exists that won’t take a while to recuperate from the arrival of Daylight Saving Time, which started today. Days later, all sorts of clocks — from car to microwave to DVR – will remain an hour behind. Morning minds are discombobulated as people ask themselves: Why am I up so early?
 

Many also ask: Why endure such annoyance twice each year? The answer: to save energy and maybe ourselves.
 

As long ago as 1784, Benjamin Franklin proposed a daylight saving time to save on candles, but it wasn't until World War I that the United States enacted saving time to conserve fuel for the war effort. Since more people are active late in the day than early in the morning, extending natural light in the evening reduces the need for artificial light and the energy required to produce it.
 

The fossil fuels that generate most of our electricity are not an endless resource. Nor is the atmosphere, which burnt fuel continues to befoul. So adding light to conserve energy and cut the poisons we breathe seems worth the semiannual annoyance of time changes.
 

Perhaps then, a name change is needed, something that better reflects what the time change all about.
 

How about Life-Saving Time?

Friday, March 07, 2014

The dead meat flower

Skunk Cabbage in full bloom
This is the season when we search the yard for snowdrops and crocuses, popping through the melt. Yesteryear’s farmers, however, looked not for these elegant garden imports, but for a reeking native to find signs-of-spring comfort.

Skunk Cabbage is by far our earliest wildflower, often appearing even before all the snow has disappeared. Well supplied with antifreeze, Skunk Cabbage also generates heat by a process called thermogenesis. Inside the cabbage hood, which protects a ball of flowers, the temperature can be as high as 70 degrees when the outside air is freezing.

That heat, plus plenty of pollen, makes the Skunk Cabbage very user-friendly to some of the season’s first insects, which may gain not only food, but warmth, on an early spring day. Many of those insects were attracted by the plant’s stink, which is reminiscent of rotting flesh – just what a hungry fly loves!

Skunk Cabbage is clever in other ways, including its flavoring. The plant is rich in blistering oxalates that “burn” the tongue and discourage browsers. It’s a defense that has prevented deer from decimating its wetland colonies.

Wednesday, March 05, 2014

Winds of life

March is famous as the month that is supposed to roar in with leonine force, pruning some trees and felling others. But in the world of trees, the March wind is a new-life giver as well as an old-life taker.
 
As any allergy sufferer knows, trees produce enormous amounts of pollen – a single tassel of birch flowers can disperse 10 million grains. March winds can bear the pollen of red maples, American elms, ashes, willows, and other early bloomers to fertilize distant flowers, leading to seeds and, if all goes well, a new tree.

The wind is a reliable, effective vehicle for arboreal intercourse. Some years ago, the Paris Botanical Garden had a pair of female pistachio trees that bloomed for years but never fruited. Then one year, both were full of nuts. A researcher found that some miles away, on the other side of the city, someone's new, male pistachio had bloomed for the first time that year. 

While a high wind in March may spell the end for a few old trees, it can also bring life to many others.

Monday, March 03, 2014

Bundling bluebirds

A correspondent told me a few years ago about a remarkable example of birds’ dealing with the cold.
“Recently, on a day when outside looked very white as snow was falling and already covering the ground, my husband and I witnessed a burst of color. Late in the afternoon, we saw about eight bluebirds sitting in the tree near our birdfeeders. Much to our surprise, some of them visited our feeders. This was our first experience at seeing bluebirds do this so we knew they must be very hungry.
“Most interesting, however, was what happened as the sun set. We witnessed a well-organized entry into a bluebird house at the edge of our yard. At least five of the birds seemed to squeeze themselves into the little house. Since that evening, we have observed this behavior several more times. We are delighted to provide shelter for our little friends.”
A number of species practice communal “bundling,” as the old New Englanders called snuggling on a cold winter’s night, but this was the first time I’ve heard of bluebirds doing it.
A check of Arthur C. Bent’s venerable and huge (21 volume) series, Life Histories of Familiar North American Birds, provides some interesting accounts of bluebirds in similar situations.
Bent quotes an item in a 1937 Springfield, Mass., newspaper, "Mr. Cross of Huntington has a photograph of 22 bluebirds together which, caught in a heavy spring snowstorm, lived upon sumac berries and, between feedings, snuggled together, all fluffed up, on a small dead branch in the shelter of a building."
Bent quotes Edward H. Forbush reporting in 1929, "In western Massachusetts and in Vermont during the late spring storms, many bluebirds have died huddled together in hollow trees, where they sought refuge from fury of the gale. During a storm, a lady in Stowe, Vt., heard a bluebird calling in her living room and found two in the stove. They had sought shelter in the chimney and had come down the stovepipe."
But perhaps the most amazing story – if it can be believed – came from that 1937 Springfield newspaper: "On March 28, a pair of bluebirds came to the feeding station of Charles J. Anderson, 24 Eddywood Ave., Springfield, and after eating began to flutter and peck at the window. It was cold outside, so after talking to them through the glass, Mrs. Anderson let them in. The male was hardy, but the female manifestly required warmth. She was given warm milk to drink, and warbled her thanks. For three days, while the cold spell lasted, she returned periodically to get warm inside the room."

Saturday, March 01, 2014

Old Number One

March isn’t what it used to be. Oh, sure, it’s the only month with a command – March 4th – and yes, it was named for a commanding god. But March used to be Number One.

Mars, relaxing
Early calendar designers in the Northern Hemisphere were logical. March is the month of spring’s arrival, the time when life returns to the earth – a reasonable place to begin a new year. So the Romans made March the first month. So did the Saxons, who called it Lenet Monat, or length month, referring to the longer days. Even until 1752, the British considered March 26 the beginning of the legal year.
Since the month was so important, the Romans named it after a leading deity, Mars, their god of war. The Romans were, after all, a militaristic nation, conquerors of much of Europe.
Alas, the reshuffled modern-day calendar gives us a leading month, in the dead of winter, that’s named for Janus, the god of doors. Yes, doors.
Let’s face it: The whole year isn’t what it used to be.