BIRDS OF NANTUCKET
ANOTHER DISAPPEARING BIRD?
by Kenneth Turner Blackshaw
You all remember the question: "If a tree falls in a forest and no one is around to hear it, does it make a sound?" As an aside, there is now a feminist corollary: "If a man says something in a forest and there is no woman to hear it, is he still wrong?" Our bird this week brings up a similar question: "If something disappears that no one has noticed, should we care?"

Vesper Sparrow

We are discussing the Vesper Sparrow, just another Little Brown Job (LBJ). It was given its name by John Burroughs, the grand old man of nature of the late 19th century. John named it for its lovely evening song although you can hear it all day when it is on its nesting territory. Perhaps we miss hearing this song on Nantucket because of its similarity to the very common Song Sparrow that sings from almost every bush here during spring and summer.

This is a small 'sparrow-sized' bird, mainly brown above and white below. The throat and breast are streaked with black and the markings on the face appear somewhat washed out and indistinct. It has a faint eye ring. With luck you can spot its rusty wing coverts that provided reason for its old name, the Baywinged Bunting. The best field mark is their white outer tail feathers that flash as the bird flies away from you. As in most of the sparrow clan, males and females are identical.

The white tail feathers sound like a great identification aid, but the trick is getting one to fly at all since they are happiest hiding amongst the long grasses. My last sighting of one on Nantucket was several years ago about this time of year when we flushed one near the Warren's Landing road on the island's west end.

The bird's interesting and somewhat redundant scientific name, Pooecetes gramineus, means literally 'grass dweller of the grasses.' The bird is so unique that it is the only living member of the genus Pooecetes. Its closest relative is the Lark Sparrow, a western bird that also sports white flags on its tail. Spencer Fullerton Baird was the namer of this bird. Baird lived from 1823 until 1887. His 1838 meeting with Audubon sparked his interest in ornithology. He was Assistant Secretary and then Secretary of the Smithsonian Institution from 1850 until his death. Interestingly he died right across Nantucket Sound at the Woods Hole Marine Biological Laboratory, an institution founded mainly through his own efforts.

Vesper Sparrows are ground nesters. They scrape a depression at the base of a grass tussock and that's where they build their woven grass nest. This nest is built in late April or early May and the growth of spring vegetation during that time quickly makes it almost invisible. They lay four eggs and frequently raise two broods each season. A favorite and unique behavioral characteristic is their enjoyment of a good dust bath. Not all species of birds do this. It's thought that dust bathing kills lice, mites and other pests, essentially asphyxiating them. It also assists in feather maintenance.

The bird books show Vesper Sparrows as nesting all across the northern U.S. and southern Canada. But particularly in the east, this species is considered threatened, mainly due to habitat loss. Even similar appearing species often have very different needs. A pair of Vesper Sparrows typically requires five times as much territory as a Song Sparrow to nest. Reforestation, urbanization, the use of chemicals, and early harvesting of hay have all contributed to the decline of this species.

On the other hand, Vesper Sparrows are among the first species to occupy grassy areas created when strip mines are reclaimed. This has allowed them to become more common in once-forested areas in West Virginia and surrounding states. So our loss in the east is their gain.

Although the literature shows this sparrow being a rare summer resident on our island from April to late October, now is the best time to see them. Is it their secretive behavior that causes these LBJs not to be reported every year or are they more scarce? The fact that they are threatened in our region gives us reason for concern and takes us back to the initial premise for this article. They may be diminishing and we just don't realize it.

My feeling is we should care about this and even be alarmed. Every species plays its part in the web of things, so Vesper Sparrows may be critical in ways we can't imagine. If you are fortunate enough to actually hear a Vesper Sparrow sing, perhaps you will be moved, as John Burroughs was, and sense how the melody captures

the spirit of the approaching twilight. I

George C. West creates illustrations for these articles. If you enjoy 'social' birding, join the Nantucket Bird Club at 8 a.m. Sundays in front of Nantucket High School for a two to three hour birding trip. Call 228-1693 for more information. 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.