Naturewatch: It's an upside-down world for the nuthatches
— Margie, Bennington, Vt.
A:A better question in this area, as we have two different nuthatches here, the white-breasted and the red-breasted, is why do they almost always perch and walk upside down. First, it is interesting to learn that most woodpeckers and creepers find their food on tree trunks and larger branches by working their way upward, giving them a good perspective of insects tucked under loose bark that other birds often miss. They rely on their stiff tails as a brace, and if an attempt was made to head down head-first, they would topple over. By working upward, they mostly miss insects tucked into loose bark only viewed from the top, and it is the duty of our nuthatches to gather those.
In fact, nuthatches are not built to easily walk up a vertical trunk or branch (although they sometimes do when maneuvering around) — they don't have the stiff tail feathers to prop themselves upright while foraging. These little birds instead have extra long backward-pointing toes with sharp toenails that allow them to cling to a tree with one foot and brace itself with the other, allowing for downward progress.
Foraging upside-down, nuthatches make good neighbors in the mixed flocks they often travel with. They aren't in competition with these other wintering birds, including black-capped chickadees, tufted titmice, hairy woodpeckers, brown creepers and dark-eyed juncos. At our feeders, I would add house finches that also arrive with the before-mentioned songbirds.
Look for the largest of the North American nuthatches, the white-breasted, at all seasons in deciduous woodlands and suburban areas, especially noticeable at feeding stations. It is said that they travel during the winter with other birds because the more eyes in a group, the easier it is to find food, which may be the reason behind all mixed flocks. White-breasted nuthatches are easily identified, and are gray-blue on the back, with a white face and underparts, a black or gray cap and neck frame the face.
The energetic red-breasted has become more noticeable since the mid-20th century at lower elevations. Until then, they were more often found in evergreen forests at higher elevations, and we would find them in spruce-fir stands on the Berkshire Plateau regularly. In recent years, it has become an almost regular feeder visitor in many locals. It is smaller than its relative and sports a black cap and black stripe through the eye broken up by a white stripe over the eye. Its underparts are rusty-cinnamon, and somewhat paler in females.
Q:Why were there so many gypsy moths this past summer? Hadn't seen them in years.
— Phil, Great Barrington, Mass.
A:Yes, it has been more than 30 years since such a widespread outbreak of gypsy moths occurred across Massachusetts, Rhode Island and Connecticut. I noticed only localized defoliation, but didn't travel much during the season. It came as a surprise to researchers, who discovered the outbreak and eventually linked it to the drought.
Thom Smith welcomes your questions and comments. Email him at Naturewatch@live.com or write him care of The Berkshire Eagle, 75 S. Church St., Pittsfield, MA 01201.
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