For my last Friday Feathered Feature, I wrote about a bird that my group encountered during Faville Grove’s participation in the Waterloo Christmas Bird Count (CBC), the Northern Shrike. This week, I’d like to focus on a species observed by our other group, a bird who always looks like it just lost a bar fight: the Red Crossbill.
Making their way around the Kettle Pond at Faville Grove, the CBC team heard the calls of what they believed was a Red Crossbill coming from a row of red pine on the northern edge of the pond. After further listening they were able to confirm it and record a call, and one individual was added to the count.
Red Crossbill (photo via Pixabay).
The Red Crossbill is a species found predominantly in northern and central parts of the state, where its diet of coniferous seeds is found much more plentifully in mature stands of pines, hemlocks, firs and spruces. Their distribution is more related to cone crop density than acreage of suitable habitat, and crossbills are often seen further south following heavy cone crops throughout Wisconsin’s many disparate pine plantations. Though most of Faville Grove’s conifers are not native to the habitats they appear in, they do provide contingent habitat for irregular species such as the Red Crossbill.
After volunteer Michael Kamp uploaded the call audio in eBird, Faville Grove champion eBirder Aaron Stutz determined that the individual fell into the Type 2 (Ponderosa) subclassification. Researchers have identified ten North American populations of Red Crossbills, each with distinguishable calls and differing morphology, genetics, and ecological associations. Certain populations have been deemed sufficiently distinct to warrant classification as separate species, such as the Cassia Crossbill, formerly Type 9. The population our individual fell into, Type 2, is predominantly found in the ponderosa pine forests of the American West, but can be found throughout the continent and is the most common call type within Wisconsin. Their diet is eclectic but shows a preference for hard-coned pines such as ponderosa, lodgepole, jack, and the red pine our individual was observed in.
A 2017 Red Crossbill irruption brought in many call-types that had never been observed in the state, so perhaps we’ll be able to identify additional types within the sanctuary in the future. They’ve proven themselves a very nomadic species, following the cones wherever they drop. Even if we’d like there to be fewer pines in the sanctuary for the sake of native habitat, we’re happy to host the Red Crossbills while they’re around.
Written by Tucker Sanborn, Faville Grove Sanctuary land steward
Cover photo via Pixabay. A rusty male Red Crossbill and a yellowish-colored female drink from a shallow pool.
