When evolutionary biologists decide that one sub-population of birds has been isolated from all others, does not interbreed, and has evolved enough genetic differences to suggest many thousands of … ...

CHICAGO — After walking the grounds of the Morton Arboretum for hours on a December morning, John Leonard and fellow birders were preparing to go to lunch when they encountered a rare sight: a ...

Red crossbill calls are usually loud enough that a recording made with your phone is sufficient to identify the call type. Type 12 red crossbills are the most common type in Maine.

Red crossbill types are based off a number of categories, including call type, bill morphology, body size and conifer tree preference. In fact, a new species was named in 2017, ...

Red crossbills are especially interesting for ornithologists, those who make a profession of studying birds. Here’s a paragraph from the American Ornithologists Society’s monograph on the ...

Red crossbills of different populations tend to specialize on particular conifer species: on ponderosa pine, or hemlock, or Douglas fir, or lodgepole pine, for example.

Reports of a few Cassin’s finches and some red crossbills came next, but numbers of the latter have really exploded, with flocks traveling from one stand of ornamental pines to another.

Lesser goldfinches feast on the seeds of weedy, invasive plants such as thistles and dandelions, which are abundant in the ...

Red crossbills, small colourful birds with a parrot-like appearance, were particularly numerous this year as they passed over the Col de Bretolet in the Swiss Alps. The ringing station there ...

Starting in late summer 2023 red crossbills appeared in southern Maine in large numbers, likely driven by the abundant pine cones. Sign in or Subscribe See Offers. Sign In: Login.