Wild Side: Wintering with us, the hermit thrush

You may encounter it hunting for berries.

An adult hermit thrush. — Courtesy Audubon Society

On Friday the 21st, I surprised a hermit thrush as it fed on multiflora rose berries next to the building I work in. The next day, I spotted one as it darted across Lambert’s Cove Road in front of my car. And around sunrise on Sunday the 23rd, I was surprised to flush a hermit thrush out of an American holly bush in our yard, as the bird fed on holly berries and I ambled out to retrieve our newspaper.

While a hermit thrush is indisputably a drab bird, brown and essentially unmarked above, I actually find this species to be easy to recognize. It is larger, less reddish overall, and possessed of a much longer tail than a Carolina wren. It’s browner and much smaller than an American robin. Hermit thrushes approximate of most of our sparrow species in size, but the latter are all chunkier birds, and their streaked plumage, even if not seen clearly, registers very differently to the eye than does the flat brown of a hermit thrush. The cues are subtle but, with practice, reliable: Nothing that normally occurs on the Vineyard in the winter matches the size, shape, proportions, and especially the particular shade of brown of a hermit thrush.

Hermit thrushes require a closer look during the peak of migration, when very similar close relatives such as Swainson’s and gray-cheeked thrushes are possible (though never common). The classic field mark for hermit thrush can sometimes be hard to spot, but in all of the three sightings I mention above, it was immediately evident: The tail on this species is always at least slightly reddish, contrasting noticeably with the muddier brown of the back.

Again, I suppose this mark can be obscure to untrained eyes. But to experienced birders, it’s obvious, given good light and a good angle, and often visible even in a momentary glance in bad light. Hermit thrushes are rarely found more than a few feet above the ground, so viewing one from human height often makes that contrasting tail obvious. During summer, the only other thrush that occurs here is the wood thrush, uncommon and perhaps declining as a breeder in up-Island deciduous woodland. While the song of that species resembles that of the hermit thrush, the bird itself is larger, redder, and more robust.

Hermit thrushes may still nest on the Vineyard, but if they do, I for one don’t know where they’re doing it. Breeding Bird Atlas surveyors found a few pairs during their 2007–2011 project. For years, a pair nested in a stand of pines at the western end of the Frisbee golf course off Barnes Road, in the State Forest. (Here or elsewhere, hermit thrushes generally nest amid conifers.) Perhaps the human activity associated with the course discouraged the birds, but in any case, it has been a decade or so since I’ve heard this species sing from those pines.

Other pairs used to nest in pitch pine stands in the Pohogonot section of the State Forest, south of the West Tisbury Road, and farther south on private property near Job’s Neck. But again, I’ve missed those birds in recent years, and not through lack of trying.

If they’re gone, it’s a shame. The song of this species is one of the most beautiful sounds in nature, a series of short, ethereal, flutelike phrases, alternating from slightly higher to slightly lower in pitch. Wintering birds never sing, but they do give a characteristic, soft “tuck” note when they’re curious about something, and many of the hermit thrushes I encounter come to my attention through that note.

Breeding status aside, this remains a reliable migrant and wintering bird, scarce during spring migration, but regular in modest numbers from September into the winter. The place to find them at that season is in wet thickets: A good tangle of cat briar near a stream or seep is ideal from a hermit thrush’s perspective, providing concealment, shelter, and a supply of berries, of which hermit thrushes are inordinately fond. (They also eat invertebrates of all kind, and even small vertebrates, up to the size of a hefty salamander.) At least a few hermit thrushes linger into January and beyond each year, and unless the weather is truly egregious, some or most of these hardy, resourceful birds persist until early spring, when they quietly depart.

The birds I found in late February were undoubtedly wintering birds, not early migrants, and had probably moved out of the thickets they wintered in either because they had run out of berries to eat, or because the lengthening days was starting to make them restless. There are surely still hermit thrushes present on the Vineyard as you read this, but sometime over the next few weeks, they’ll head north, giving no sign of their departure.