BIRDS OF NANTUCKET
SIZE MATTERS?
by Kenneth Turner Blackshaw
There are seven bird species named "least" on our list of U.S. birds and seven more named "lesser." So there are 14 birds named just for being smaller or smallest.

Least Tern

A few weeks ago we looked at the Royal Tern and learned that its Latin name, Sterna maxima, tells us it is the largest tern, but it's really not. This week's bird is one of the least - the Least Tern. Its Latin name, Sterna antillarum, makes no reference to size. Instead, it's a place. The original specimen came from way down in the Caribbean in an area known as the Antilles.

In this case the name "Least" is accurate. These graceful little "sea swallows" are our tiniest terns. Until recently, it was considered to be the same species as the Eurasian "Little Tern." I wrote another article about this common Nantucket summer bird "Lee Stern," and you can check that out in "A Year of Birding Nantucket," Volume One, available in all Nantucket bookstores.

If you are a beach person, you'll undoubtedly see this bird every time you go there. As you look out over the water, you may see twinkling silver figures flying gracefully, long of wing and swallow-like. Occasionally they will dive dramatically toward the surface, sometimes pulling back up abruptly to resume their search, other times splashing neatly into the water. They swoop back up, shaking the water from their wings as they do, hopefully with a silver fish in their bill that is then quickly swallowed.

Terns are closely related to gulls. Some small gulls, like the Bonaparte's, can be confused with terns. But terns have longer, slimmer, more pointed wings and often show long swallow-like tails. Most are silver gray above, white below, with black caps. You have to tell them apart by bill or leg color, or subtle differences in wing shading, tail length, or size.

Size can be hard to judge in flight but what you notice with Least Terns is their rapid wing beat, often too fast to count the strokes. If you see them sitting on the beach look for their white forehead ahead of the black cap. In summer they are the only terns with yellow bills, but as the season progresses they gradually turn black from the tip toward the head.

Least Terns were horribly persecuted in the late 1800s and early 1900s. Their feathers and whole bodies were used to adorn ladies' hats. Along the Virginia coast as many as 100,000 were killed in a single year. They would be packed in ice and then sent to the milliners in New York City, bringing up to 12 cents apiece. The result over years of this practice was that once abundant breeding colonies were reduced to a pitiful few.

A Least Tern's nest is not a traditional nest at all. They like open beaches with just a scattering of pebble or shell fragments. They lay their two eggs in a small depression, the eggs being the same color as the sand and flecked with marks that make them blend in even further. The background color is described as a rich 'cartridge buff.'

In just over two weeks, the eggs hatch and produce fluffy chicks of much the same color as the eggshell. Unfortunately this wonderful camouflage makes it very easy to walk or drive on them. After a few days they can run like the wind. This presents an irresistible temptation for most any dog, another reason why dogs are banned from most Nantucket beaches and required to be leashed on others.

There are seven Least Terns in the Edith F. Andrews Bird Collection at the Maria Mitchell Association. The details of their deaths show that man is still their major enemy. One died tangled in monofilament fishing line. Two others were found crushed to death in vehicle tracks on the beach.

Fishermen have a love-hate relationship with terns. Sometimes good fishing beaches are off limits due to nesting activity. But at other times, seeing a cloud of terns hovering and diving over the water leads them to the spot where the bluefish are driving the bait to the surface.

Nantucket is close to the northern edge of this delightful little tern's nesting range. They nest along the ocean coast south to Florida and around into the Gulf of Mexico. They are also found on the Pacific Coast. There's a tiny population that nests around ponds in the prairie states that is considered to be endangered.

With luck and good parenting, this year's crop of Least Terns will soon be on the wing. They'll have to test them soon since Least Terns don't hang around long in the fall. The shortening days cause them to think of their winter homes in South America and they are usually gone from the Nantucket beach scene by mid-September. Least, lesser, or greatest, they are a charming

part of our summer beach scene. I

George C. West creates illustrations for these articles. The Maria Mitchell Association sponsors bird walks on Tuesday and Thursday morning starting at 6:30 a.m., 8:00 a.m. on Saturday, from the corner of Vestal and Milk Streets. There is a fee. To hear about rare birds, or to leave a bird report call the Massachusetts Audubon hot line at 1- 781-259-8805. Ask Ken a question at: kenandcindy1@comcast.net.