Generalist habits good for survival of plover variety

By Chris Corio, Special to the News
Posted Oct. 29, 2010, at 7:03 p.m.

A walk on my local beach isn’t always conducive to good bird sightings, unless conditions are just right. Those conditions usually include low or midtide, cool weather (thus the absence of beach-goers) and the absence of dogs.

Only two of those conditions were met the last time I birded along the beach, so I was pleasantly surprised to see the birds I did.

The tide was low but starting to come in again. The weather was cool enough to discourage large numbers of beach-goers, but just the right temperature for people to exercise their dogs.

I had turned right after entering the beach and headed down to Fisherman’s Point. Certain areas of the beach are more inviting to people at certain times of the year. In summer, the water temperature between the freshwater outflow stream and the point is higher, and a great place for children to look for hermit crabs. In winter, the angle of the incoming tide is steeper and the wave action much different; here, the flat sand is often littered with rocks of various sizes, as well as large mats of washed-up seaweed.

This area of the beach is not as inviting to people at this time of year, making it available to wildlife. I’ve seen a red fox foraging among the racks of seaweed at the high-tide line and making runs at ducks paddling in the shallows. And it is the place where I’ve had my best bird sightings.

As I approached Fisherman’s Point, movement on the sand flats captured my attention. I was delighted to see small shorebirds scuttling along foraging for food. I focused the binoculars on them; they all were in winter plumage, their upper body feathers brown, their underbodies white with a single breastband. Their bills were small and lighter at the base than at the tip, and their legs were pale orange. They were semipalmated plovers.

The birds — eight of them —were foraging among the small tide pools and ripples in the sand. It seemed they were certainly getting a lot to eat, constantly pulling sandworms from beneath the substrate.

At one point, something spooked them because they suddenly all squatted down and flattened themselves to the sand, becoming still as statues. If I hadn’t caught sight of them beforehand, I never would have known they were there; so completely did they blend with the color of the wet sand. I looked around, expecting to catch sight of a merlin or another bird of prey. There were none that I could see and eventually the plovers relaxed, rose on their short stilt legs and resumed foraging.

In North America, semipalmated plovers breed in the arctic and subarctic stretching from Alaska to Newfoundland. Their habitat is open tundra, sand and gravel bars of rivers, and beaches and sand dunes. Come autumn they migrate to winter in Central and South America, as well as southern points along both eastern and western seaboards and the Gulf Coast of the United States.

Shorebirds have been in decline and certain populations are constantly threatened by human encroachment on breeding areas, as well as habitat loss and degradation. However, according to the “Birds of North America” species account, the semipalmated plover is one of the few plovers whose populations seem to be increasing. This is a result of the bird’s generalist habits — it uses a wide range of habitats and food choices.

The eight plovers I observed also were lucky that no rambunctious humans or dogs broached their quite spot on the beach that day. They were allowed to continue feeding and fattening up for migration until the tide came in.

http://bangordailynews.com/2010/10/29/outdoors/generalist-habits-good-for-survival-of-plover-variety/ printed on July 30, 2014