Category Archives: Migrations

A Twisted Tale of Red Knot Survival

By Joanne Garton

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It has happened countless times: I walk into my favorite restaurant only to find that it is out of breakfast burritos. The manager points me to the tamales without ever explaining if it was a lack of eggs, a problem with the oven, or an angry mob of hungry burrito-eaters that wiped out the supply this weekend. I leave hungry and find somewhere else to eat.

These days, the red knot birds in Delaware Bay are similarly exasperated, but with no other food to eat when their seasonal feast of horseshoe crab eggs are gone, the migratory birds are starving. Horseshoe crabs are the favored bait for a growing market of eel and conch farms, diminishing the supply and diversity of breeding horseshoe crab pairs left in the bay. Continue reading

In Search of Herps

SpottedSalamander800x600April showers bring more than May flowers, and birds aren’t the only creatures producing fantastic choruses in the springtime. While birders will set their alarms for 5:00am in order to catch the rainbow of spring migrants arriving in Vermont, herpetologists – that is, aficionados of amphibians and reptiles – will spend the wee hours of the night up to their knees in muck and water to glimpse the bizarre courtships of frogs and salamanders.

Continue reading

Lessons from Snow Geese

SnowGeeseBeating wings fill my view. The snow geese are stark white, and the black tips of their wings pulse in contrast with their bodies. Hundreds – no, thousands – of these meaty birds move in unison. They squawk and honk, thousands of calls melting into an urgent and persistent roar.

At least that’s what I envisioned.

I had never seen snow geese, but I set out confidently to find the birds. I wanted to feel the wind from a thousand birds taking off at once. I wanted to feel their thunderous calls in my chest. Continue reading

Natural Destinations: Dead Creek Wildlife Management Area

by Cathy Bell

(originally posted on vtdigger.org)

Every autumn, thousands of snow geese take a break from their 5,000 mile southbound migration to rest and feed at Dead Creek Wildlife Management Area in Addison, Vermont.  Journeying from their breeding grounds on the Arctic tundra to their winter range in the mid-Atlantic and southeastern states, the snow geese are but fleeting visitors to the Green Mountain State, descending on our cornfields from October into early November.

The bright white feathers of a snow goose’s body contrast with tips of the wings, which look as though they have been dipped in paint of the richest black.  Young birds are brushed with gray on their backs, giving them a dirty appearance.  Here and there among the flocks are dark gray individuals with white faces.  These steely-looking birds, commonly known as “blue geese,” are the same species as the white ones.  Snow geese of either coloration are far prettier, to my eye, than our resident Canada geese.  Getting to see these visitors from the north is a seasonal treat.

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Snow geese at Dead Creek

Hoping to find some snow geese, I went to Dead Creek on Saturday, October 30.  The day started out sunny but clouded up as the big Halloween nor’easter worked its way towards New England.  Driving down Route 22A from the north, I made a right turn onto Route 17.  I had gone less than a mile from Addison Four Corners when I saw a wheeling flock of waterfowl.  Backlit, the winged forms did not reveal any details of their plumage, but the size and flight pattern didn’t seem quite right for Canada geese.  Even as I thought to myself that I must be in the right place, I saw a turnoff on the south side of the road.  I pulled off the highway, shut off the ignition, and hopped out of the car, binoculars in hand.  Looking to the south, I felt my jaw drop in wonder.

About 800 geese were in a field very close by, in easy sight of a viewing platform with interpretive signs.  Hundreds more were in a distant depression.  From the knot of people with binoculars and spotting scopes a quarter mile to the west, I guessed there was another—possibly even bigger—group of geese over there too.  Aerial photo counts that weekend documented more than 4,600 geese in the area, but few people braved the chill wind of the gray afternoon to witness the impressive spectacle.

A northern harrier, its white rump patch catching the watery light, startled the nearest geese into rising from where they rested and fed.  Within moments, the nervousness of a few waterfowl swept through the flock, and hundreds of birds were in the air, honking their discontent in a higher-pitched and more tremulous voice than that of the familiar Canada goose.

Though I looked carefully, I failed to find any Ross’s geese among the swirling clouds of white waterfowl.  Snow geese and Ross’s geese are two distinct species, though very similar in appearance; the rarer Ross’s is more diminutive in build and has a smaller bill.  I later read on the Vermont bird listserv that there were indeed two Ross’s geese at Dead Creek that afternoon, but they were the needles in the haystack of thousands of snow geese.

I may have lucked into witnessing the peak of this year’s snow goose migration, but there’s still time for you to see the spectacular waterfowl as they pass through Vermont.

At 2,858 acres, Dead Creek Wildlife Management Area is administered by Vermont Fish and Wildlife and includes extensive reaches of cattail marsh and stretches of open water.  The geese, however, are concentrated in upland agricultural fields.  The designated goose viewing area along Route 17 is the best place to see the birds, but a little farther south, Gage Road can provide good sightings as well.

Moreover, though the snow geese may be the star attraction, there is more here for inquisitive visitors to enjoy.  Northern shovelers and green-winged teal dabble in the shallow, ponded water of the fields, and once in a while a pectoral sandpiper passes by overhead.  A quarter mile west of the goose viewing turnoff, Route 17 crosses the still, murky waters of Dead Creek.  Mallards and black ducks ply the waters here.  Just over the bridge, a left turn takes you down a gravel road towards a hunters’ camping area.  Look along the reedy edges of the water for great blue herons and wood ducks.  Despite its name, Dead Creek is a lively place.

The creek flows northward, parallel to the southernmost portion of Lake Champlain.  Just seven miles north of where it flows under Route 17, the creek joins with Otter Creek and soon wends its way into the lake.  Its meandering path has been modified by the addition of dams, and today, the state actively manages water levels in the flooded impoundments.

The snow goose hunting season runs from October 1 – December 29 in the Lake Champlain waterfowl hunting zone, with a daily bag limit of 25 birds.  Portions of the Dead Creek Wildlife Management Area, including the upland areas south of Route 17 near the viewing area, are managed as a refuge where no hunting or other public access is permitted.

More information, including maps and directions, is available from Audubon Vermont and Vermont Fish and Wildlife.

Why do birds fly south for winter?

by Doug Morin

I opened my backdoor and stepped into the yard to a flash of red and buzz of wings – a hummingbird.  Maybe the last of his kind I will see this year, he perched on a small branch, tilted his head to either side, then flew off down the road.

Here in Vermont, hummingbirds disappear in late September and reappear in late April.  We know the story well: birds fly south for winter.  Of course they do.  But, have you ever wondered why?

First, let’s turn the clock back a few thousand years.  It turns out, most migratory birds in North America trace back to ancestors that lived in the tropics.  Over time, these birds expanded their ranges until a small proportion eventually made it to North America.  Even today, most birds arrive in late spring and leave in early fall – spending less than half their year in North America.  The real question then isn’t, why do birds fly south for winter? but, why do birds fly north for the summer?

This is a particularly important question because migration carries a deep cost.  It’s easy to discount the effort required to fly to and from the tropics, given the convenience of modern air travel (though I’d still like more leg room), but the journey for a bird takes huge amounts of time and energy as well as exposing the bird to unfamiliar environments and predators.  The hummingbird in my yard, for instance, weighed only as much as small handful of paperclips, yet over the next weeks, it will first fly to the southern coast of the U.S., then across the Gulf of Mexico to the Yucatan Peninsula in a single, non-stop flight lasting nearly 24 hours, and finally overland to southern Central America.

The time, energy, and risk involved in migration have severe impacts: migratory birds are twice as likely to die in any given year, compared to tropical non-migratory birds.  So, why in the world do they do it?

The answer is that the benefits outweigh even these high costs.  Since relatively few birds come to North America, migrants have easy access to abundant insects, plants, and nesting grounds.  With plentiful food and territory, migratory birds produce many more offspring each summer than their non-migratory counterparts.  As winter arrives, however, insects and plants disappear, and the diminished food supplies (rather than dropping temperatures per se) drive migrants south.

Overall, migratory birds do not live as long as non-migratory tropical birds, but produce more offspring each year – resulting in nearly the same number of over their lives.  Since the number of offspring determines how many birds will be in the next generation, these two strategies are roughly equivalent in evolutionary success.

So, the birds that grace our summers with color and song do so for windfall payoffs, but at immense cost.  As you see the last of our migratory birds leaving over the next few weeks, wish them well on their way.

Also, look out for a more in-depth post by Emily Brodsky on Raptor Migration in the next few days!

 

Note: For excellent maps of where birds spend their summers and winters, see the Cornell Lab of Ornithology’s website All About Birds.