I am now contributing to the FaceBook page for the Terlingua Ranch Lodge. Weekly posts focus on wildlife: plants and birds, in addition to posting photos of recent events around the Lodge area (music in the cafe, etc).
Today’s post focused on the Blue Grosbeak, a member of the Cardinal family and the Passerina genus, which also includes buntings. Most birds of this genus are characterized by large or thick conical beaks used for breaking seed. Most of these are usually solitary, but are often found in small groups. On the other hand, several of the true grosbeaks (evening and pine grosbeaks; Pheucticus genus) are often gregarious and sometimes raucous when clustering at bird feeders. Typical of most members of the Cardinalidae family, the males are brightly colored and the females are generally plain, marked with dull brown and some greenish plumage.
Male blue grosbeaks have similar coloration to indigo and blue buntings. Discerning differences are the bi-colored beak, usually dark upper and light gray lower, and is much more stout than beaks of the buntings. Additionally, the blue grosbeak has a black mask around the eyes and extends only to the base of the beak. The mask of the blue bunting, on the other hand, is minimal and usually extends behind the eyes, curving down to the shoulder of the wings. Also, the blue bunting also has shades of lighter and brighter blue on the forehead, the rump, and the bend of the wing. A deep blue plumage is more consistent on the blue grosbeak except for rust and black banding on the wings.
Both the indigo and blue buntings have predominantly blue wings and tails, interspersed with some black feathering. The wings and tail of the blue grosbeak, however, are predominantly black and the ends of the tail feathers are round with white stripling.
Range: Historically, the summer range of the blue grosbeak has been reported throughout mid-central and southern US and south into Mexico. Although their winter range usually extends north only as far as south of the Rio Grande near the Gulf, they may be shifting or expanding their winter habitat northward in response to climate change and habitat pressures. The bird photographed was spotted this fall in the Chisos Mountain area of Big Bend.
Nests: The deep, cup-shaped nest of the blue grosbeak are typically found on a branch of a tree or bush 3-8 ft above ground, is made of leaves, plant stems, rootlets, grasses, strips of bark, and sometimes bits of snake skin. Nests are lined with smaller rootlets, grasses and occasionally hair. The inside diameter is 2.4 in and the depth is 2 in. Egg laying in Texas has been documented in late April and young hatchlings reported in early June. Unfortunately, these birds are a favorite target of cowbirds, which are a notorious brood parasite, meaning that they lays their eggs in nests of other species.
Interestingly, the blue grosbeak is one of those species that shares some traits with one genus and another. Their flight call and plumage resemble that of the buntings more than other grosbeaks. Yet their size, both over all and beak size and egg size, are more similar to that of other grosbeaks. Ornithologists concluded that this bird sufficiently resembled other members of the buntings more than the grosbeaks that they were removed from the grosbeak genus and placed in that of the buntings. Some ornithologists even now prefer referring to the blue grosbeak as a bunting instead of a grosbeak. Another case of family and genus shuffling. But all science is about reserving the right to ‘change its mind’ as new facts or classifications surface, especially scientists. 😉