It’s always fun, if you’re a birder, to watch a new species get established in your area. And in the case of the tufted titmouse, I’ve enjoyed that process twice with the same species: once around my childhood home on the Massachusetts mainland, and then again after I moved to Martha’s Vineyard in 1997.
Older field guides and species accounts treat the titmouse, now a common bird in our region, as a southern species. Arthur Cleveland Bent, in a monograph published in 1946, puts the northern limit of the titmouse’s range quite precisely along a line between Mahwah and coastal Englewood, N.J. Prior to the late 1950s, the species occurred in Massachusetts only as a rare vagrant. But following the first nesting record in the late 1958, the species became rapidly and broadly established.
Massachusetts Audubon’s breeding bird atlas projects beautifully illustrate the changing status of this bird in the Bay State. The first atlas, based on data collected during the mid-1970s, shows the titmouse established in most of eastern Massachusetts, though absent from Nantucket and Martha’s Vineyard, and sparse or absent from higher elevations west of about Worcester.
The second atlas, with fieldwork conducted about three decades later, sees those gaps in western Massachusetts mostly filled in, with the titmouse present essentially statewide except for Nantucket, where as far as I know the species is still absent. Even in the eastern portions of the state where titmice had long been present, the second atlas showed an increasingly dense population of this amiable little bird. Overall, the current range of the titmouse encompasses all of southern New England and extends north into Maine.
While it’s possible that the northern expansion of the tufted titmouse’s range has been encouraged by climate change, this bird was marching toward higher latitudes before warmer winters and longer growing seasons had become very evident. So while climate change may have played a role, birders have generally assumed that an increase in the popularity of bird-feeding was the main driver. Titmice rely heavily on seeds in the winter, and while the species is notoriously sedentary, local populations do seem to concentrate around feeding stations during the winter.
In the warmer months especially, titmice (like most songbirds) rely heavily on insect prey. Back in the old-school days of ornithology, it was a common practice to collect bird specimens and then analyze their diets by dissecting them and examining the contents of their stomachs. Such studies generally showed a high reliance on caterpillars and insect eggs. Even in winter, these food sources continue to help support titmice, which are adept at gleaning twigs and bark crevices for dormant prey.
Colonization of the Vineyard by titmice began in the mid-1990s and was an interesting process to watch. The first inkling that species had arrived here came, oddly, not from an actual titmouse but from the discovery (in the spring of 1997, if I remember correctly) of what was obviously a hybrid between a titmouse and a chickadee at a feeding station in Seven Gates.
Pure titmice were found in the same area shortly after, and gradually the species began increasing in numbers and expanding its distribution on the island. Today, the tufted titmouse has spread to all corners of the Vineyard, though it remains scarce on Chappaquiddick; in many areas, this species now seems at least as common as the black-capped chickadee.
Why the species was so slow to arrive here and how it finally washed ashore are both good questions. The legend among birders, and perhaps it’s true, is that titmice have an aversion to flying across water, and that this delayed their colonization of the Vineyard. Whether the initial colonizers (at least one of which enjoyed an extracurricular tryst with a chickadee!) in West Tisbury were blown across the sound, mustered the courage to make the flight on their own, or got here by some other means is probably a question that can never be definitively answered.
Titmice are easy to identify, paradoxically, because their appearance is so featureless. A bit larger than their close relative, the black-capped chickadee, and similarly long-tailed, these birds are uniform gray above and nearly as uniformly white below. Most individuals show some reddish color on the sides of their bellies, a mark said to average brighter in males than in females, but this coloration is not always conspicuous or even visible.
The large, dark eyes of a titmouse, combined with its unmarked face, impart an odd, staring expression that I’ve always found a bit sinister. About the only truly striking feature of a titmouse is a tidy little crest on the head, most visible when the crown feathers are erect because the bird is agitated or excited. The vocalizations of the species are not much more distinctive. Titmice give a weak, whistled song of one- or two-note phrases. A typical call is like the “dee-dee-dee” call of a chickadee, only harsher.
The tufted titmouse is now a commonly encountered part of the Vineyard avifauna. But when I see one, it still feels a bit jarring: For many of my years on the Island, this bird was mostly just a mainland memory.