I expected to see a Black-headed Grosbeak at our feeder and, on 5 June 2019, we discovered this male at the suet. Grosbeaks are seed-eaters. Our suet is mixed with seeds and bug parts and fortified with calcium, ingredients that attract a surprising variety of birds.
Black-headed Grosbeaks are odd songbirds. First, some ornithologists consider them to be the same species as the Rose-breasted Grosbeak—just the western form of two subspecies. Females are hard to tell apart and the two types do occasionally interbreed where their ranges meet in the Great Plains. Alan Phillips considered the two forms to be the same species and named them Common Grosbeaks.
Black-headed Grosbeaks are monogamous. Males and females about equally share nesting chores. Males often take up to two years to attain breeding plumage. Second-year males are more likely to breed the more they resemble males in full breeding plumage. Females usally sing a toned-down version of the male song. Occasionally she sings just like the male. Ortega and Hill (2010) write that singing a full male song deceives “mates about the presence of intruders and forces greater nest attentiveness.”
Black-headed Grosbeaks are odd songbirds. First, some ornithologists consider them to be the same species as the Rose-breasted Grosbeak—just the western form of two subspecies. Females are hard to tell apart and the two types do occasionally interbreed where their ranges meet in the Great Plains. Alan Phillips considered the two forms to be the same species and named them Common Grosbeaks.
Black-headed Grosbeaks are monogamous. Males and females about equally share nesting chores. Males often take up to two years to attain breeding plumage. Second-year males are more likely to breed the more they resemble males in full breeding plumage. Females usally sing a toned-down version of the male song. Occasionally she sings just like the male. Ortega and Hill (2010) write that singing a full male song deceives “mates about the presence of intruders and forces greater nest attentiveness.”
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