Wild Side : Once rare on Martha's Vineyard, titmice feel at home here now
Photo by Matt Pelikan
For the last half-dozen years or so, I've been feeling a bit off-balance for much of my time in the field. I keep hearing a bird that shouldn't be here. It's a familiar call; it just sounds...wrong. But the reality is that the bird in question, the tufted titmouse, is well established on the Vineyard, fairly common in woodland from Aquinnah to Chappaquiddick. And it is my own expectation — that titmice simply don't occur on the Vineyard — that is amiss.
Encountering this small songbird, a relative of the more familiar black-capped chickadee, probably still jars most Vineyard birders: though familiar to anyone birding on the mainland, titmice were rare or absent on the Vineyard until about 20 years ago, and it is only in the last half-dozen years that Island birders have begun encountering them regularly.
Indeed, this plain, grayish bird is a relatively recent arrival in Massachusetts as a whole, with the state's first nesting records coming only about 50 years ago. One account of the species, published in 1946, treats the tufted titmouse as a bird of the Southeast, putting the northern limit of its range in New Jersey. Since tufted titmice are essentially non-migratory, few individuals strayed from the core range of the species, and this bird was virtually unknown in New England before about 1950.
But then the tufted titmouse began a relentless march to the north. Gradually warming winters may have helped, and the regrowth of forests as New England farms were abandoned probably encouraged this species, as well. But the main impetus behind the titmouse's range expansion was likely the rise of bird-feeding as a hobby: along with the cardinal, the tufted titmouse marched its way north on a diet of sunflower seeds, thoughtfully provided by bird-loving humans.
By the mid-70s, titmice had occupied most of Massachusetts and were still pressing northward. Today, their range extends well up into coastal Maine. Oddly, though, the species largely bypassed the Cape and Islands; while the first Vineyard record for this songbird came in 1948, the species was rare and only observed sporadically here for decades afterwards. The usual explanation, and it's a plausible one, is that titmice dislike flying over water. (One story, which might even be true, is that the species colonized Cape Cod by flitting across the Bourne and Sagamore Bridges.) Given an aversion to crossing water, it was only by accident that titmice would land on the Vineyard, and late 20th century records from the Island may reflect single individuals or perhaps very small groups that were driven here by storm winds or became disoriented in fog.
In 1997, famously, a titmouse-chickadee hybrid was found in West Tisbury. Such hybrids are fairly common in the bird world, generally occurring when one parent species is very rare in an area where the other parent species is very common. With no suitable mate to be found, the rare parent (in this case, a titmouse) settled for the next best thing and mated with the most closely related species available. But there must have been several titmice in the area, including at least one female, because numbers of pure tufted titmice began to grow.
Like the related chickadee, the tufted titmouse nests in cavities. A hollow tree will do, and the species will use a nest box, too. These are social, intelligent, and resourceful birds, eating a widely varied diet and often finding food in unusual places. Surprisingly for such small birds, they sometimes eat acorns in the winter, bracing an acorn in a crevice and chipping its shell with a series of well-aimed pecks from a short but business-like beak.
Curious and quite tolerant of human activity, they are frequent visitors to feeding stations. But the Vineyard titmice don't seem truly dependent on human handouts; this bird can be found in the deepest woods the Vineyard has to offer. Their establishment doesn't seem to have reduced numbers of any other birds, and this friendly and interesting species is a welcome addition to the Island's bird life.
Oddly, as my birding sensibility is finally starting to get used to encountering titmice on the Vineyard, I'm beginning to suspect that the species is growing less common. On several recent walks at conservation properties on the moraine (normally the core range of this bird on the Island), I've missed the species entirely. Time will tell whether this is just chance, or whether the species is declining. It's certainly possible, given the presumed small size of the group that founded the Vineyard population, that our titmice are weakened from excessive inbreeding. If they managed to get here, they can also manage to disappear.