Red-breasted Nuthatches are on the move. When sightings begin in August in the Garden State, it usually means we are in for a widespread and plentiful flight of this attractive little bird. Red-breasted Nuthatch is an irruptive species—turning up in large numbers some years and almost completely absent in others. Irruptions are driven by food—when conifer cone crops are poor, Red-breasted Nuthatches leave the northern and boreal forests and head south. The southward flights typically occur every 2-4 years. The species also breeds sparingly in Norway spruce groves in the northwestern corner of the state. After major flight years, Red-breasted Nuthatches have been found nesting in other places across New Jersey.
Nuthatches are well known for their headfirst, downward creeping on tree trunks and branches and their nasal, “tin horn” calls, which often sounds like “Yank…Yank…Yank.” A large back-facing claw on the hind toe allows nuthatches to maintain a firm grip on tree bark. An old colloquial name for nuthatches is “devil downhead.” Red-breasted Nuthatches eat a variety of insects including beetles, spiders, earwigs, and ants during the warmer months and switch to a diet of pine, spruce, and fir seeds in winter. The species will regularly visit bird feeders and can be fairly aggressive for such a diminutive bird. They will often cache seeds and nuts for later consumption, hiding food in crevices of tree bark.
Red-breasted Nuthatches will join foraging mixed-species flocks that often include kinglets, chickadees, woodpeckers, and creepers. Like kinglets, Red-breasted Nuthatches will occasionally form communal roosts in tree cavities to stay warm on bitter winter nights. Unlike so many other species whose populations are in decline, the Red-breasted Nuthatch population has increased across its range since the 1960’s.
Another irruptive species—Purple Finch, has also showed signs of early southbound movement, with birds recently reported from Roxbury Twp., Walker Ave Wetlands in Wayne, Chimney Rock Hawk Watch, Southampton Twp., and Cape May. Watch your bird feeders and study the books to differentiate this species from the much more common House Finch.
In other news, Wednesday August 26 turned out to be the first significant passerine migration day of the “fall” season. Chimney Rock was the standout location on that day, where several birders tallied 18 species of warblers in three hours, including outstanding counts of 20 Cape May Warblers, 20 Blackburnian Warblers, and a Mourning Warbler.
Another highlight on August 26 was the appearance of Olive-sided Flycatchers across the state. This scarce and sought-after species occurs as a spring/fall migrant in New Jersey. It nests across bogs and boreal forests to our north (as close as the Adirondack Mountains) and winters in Central and South America. The species often hunts from a conspicuous perch, usually atop a tall dead tree or snag, where it sallies out to grab aerial insects. Olive-sided Flycatchers were found in Mount Olive, Glen Gardner, Great Swamp NWR, Madison, Chimney Rock Hawk Watch, a wetland mitigation site adjacent to the Jersey Gardens Mall in Union County, Assunpink WMA, Mercer County Park NW, Palmyra Cove Nature Park, south of Chatsworth, and Cape May. Peak migration for this species occurs in late August and the first half of September.