|Melanerpes formicivorus||Order: Piciformes||Family: Picidae (Woodpeckers)|
This comical-looking species feeds heavily on acorns, and is famous for its “granaries”—trees, poles, or wooden houses covered with acorn sized holes each filled with one acorn.
Acorn Woodpeckers are communal breeders with nest helpers. A single nesting community involves two cohorts: multiple related females in one and multiple related males in the other; the male cohort is not related to the female cohort. About 1—4 females and 1–8 males are breeders, and 1–10 other birds, related to the breeders, are helpers. All the birds in the community take responsibility for defending the granary, adding more acorns to it, and feeding young.
If a breeder in a community dies, especially when a good granary is at stake, cohorts of that sex from one or more other communities come in to try to take over. Battles can be violent and cause many injuries. Birds from non-involved communities may appear to watch these battles, which provide the Acorn Woodpecker form of spectator sports.
Minnesota had two records for Acorn Woodpecker: on November 9, 2009, in Crow Wing State Park, and September 14, 2016, at a private residence in Detroit Lakes. Neither of these birds was “chasable.” Then on July 2, 2022, one turned up at Russell Stewart’s feeder and the trees on his property in Carlton County. A great many birders from throughout the state descended on his place in the following days.