There are over a dozen species of flicker, living in various parts of the Americas. The species we see here is call the northern flicker. This species occurs over most of North America, plus Central America and Cuba, where it prefers open woodlands and forest edges. The northern populations generally migrate south for the winter, avoiding areas where snow often covers the ground for long periods.
Northern flickers rarely nest around here; over the years, there has been one recorded nest in the Eaglecrest area. But we regularly get visits from them in winter, when they are seen in various places including beach fringes. There are two forms of this species, which caused taxonomic headaches for years, but they hybridize and now both forms are considered to be the same species. They are distinguished readily by the color of the underwings: the western form has reddish feathers that show when the wing is raised and the eastern form has yellow feathers there. The eastern “yellow-shafted flicker” occurs also in northern Alaska, and this or the hybrid are seen rarely in Southeast, while the western “red-shafted flicker” is the one we usually see here in Juneau, probably visiting from the BC side of the coastal range. Those colorful underwings may be flashed during social interactions.
Flickers are hefty woodpeckers, considerably larger than hairy woodpeckers. Unlike most woodpeckers, they don’t typically forage on tree trunks. Instead, they forage mainly on the ground. Their favorite food is usually ants and ant larvae, collected one by one or by hacking into ant nests or turning over scats, although they also eat other insects, spiders, snails, and fruit. That reported dietary favorite prompts a question, because Juneau is not noted for lots of ants, which are found mostly in certain habitats and are not very active in winter. So what do our visiting flickers eat? They probably depend on an assortment of those alternative food items, perhaps encountered serendipitously as they flit from place to place.
Flickers share with other woodpeckers the construction and use of nest cavities in (usually) dead trees. Both male and female excavate, but males do most of the work. When re-using an old nest, they refurbish the floor with a new layer of wood chips. Clutch size averages six to eight eggs, but this varies with location and other factors. The eggs within a clutch usually hatch on about the same day, indicating that incubation began with the last laid eggs, taking about 12 days. Both male and female have incubation patches on the abdomen, but males do the incubation at night and share the job with females during the day. Both parents feed the chicks by regurgitation from storage in a crop, and both clean the nest by removing fecal sacs, although in the last nestling period, those sacs can accumulate on the bottom of the nest, when the chicks cling to the walls of the cavity. Some clutches and broods are lost to predators such as squirrels and weasels and occasionally starlings evict the original occupants.
Chicks stay in the nest about 25 days. When they leave, they often stay together, often clinging to a tree, for a week or so, while tended by the parents. Then they start to follow the parents and eventually begin to forage for themselves. There is only one brood per year.
Chicks of both sexes mature when a year old and commonly start breeding the year after hatching. As adults, they defend an area around a nest cavity, but do not defend a foraging area, presumably because their most important food is irregularly distributed and not economically defendable. Most flickers live only a few years; the oldest known individuals were nine or ten years old.
• Mary F. Willson is a retired professor of ecology. “On The Trails” appears every Wednesday in the Juneau Empire.