Bird Watching: Blue Grosbeak

If you happen to notice a bird that has a similar blue coloring as the indigo bunting [see Bird Watching: Indigo Bunting] but looks more like a large blue finch, you might be looking at a blue grosbeak. If you are not sure, look for the distinctive large thick bill common to all grosbeaks, such as Bird Watching: Rose-Breasted Grosbeak article.]

The blue grosbeak (Passerina caerulea) at 6-7½ inches is slightly larger than a house sparrow. The male is a dark blue with chestnut-colored wing bars. (Indigo buntings, by the way, do not have these chestnut wing bars.) The female is has buff-brown colored wing bars on a darker buff-brown body. Both the male and the female do have the thick beaks of the grosbeaks, that are perfect for crushing seeds and nuts. Neither the male or the female has the prominent "eyebrow" that is so common to other species of grosbeaks. (This is another reason that they might be difficult to identify; however, just look for the thick beak.) This particular grosbeak belongs to a genus of South American tropical birds and is the only North American member of that genus.

The blue grosbeak spends the summer months in the United States from California eastward into Colorado, Missouri, southern Illinois, New Jersey, and then across the southern part of the United States. Blue grossbeaks winter in the tropics, primarily Central America. You will have to look for them in areas not inhabited by the rose-breasted grosbeak. This blue species prefers roadside thickets, overgrown pastures, and other brushy areas. Flocks of grosbeaks often invade sorghum fields in the fall to hunt for seeds and insects.

Blue grosbeaks build loose nesting cups made of stems from weeds, grass, and leaves. These nests can usually be found in shrubs, thickets, vines, or even in clumps of grass. The female lays 3-4 eggs that are pale-blue in color, while the male fiercely defends the nest. Incubation takes about 12 days, with the fledglings leaving the nest 13-14 days later.

Blue grosbeaks are not normally birds that will come to feeders; however, you might be able to attract them to your yard by planting vines, shrubs, and thickets -- anything to provide thick cover -- at the edge of your yard. You can also scatter sunflower seeds, safflower, and peanuts on the ground to coax them out from their cover. Listen for their sweet warble that sounds much like that of the purple finch [see Bird Watching: Purple Finch]. They also make a klink or chink sound when they are hunting for food.

If you live in an area where the blue grosbeak might be found, they are worth actually searching out. There is always something very attractive about a blue-colored bird, and the blue grosbeak is no exception. Plus, grosbeaks in general are just funny birds. They move rather slowly when they are eating and move just as slowly when they run other birds away, sometimes even other grosbeaks. (They can be rather territorial.) Once you find them, you will definitely want to stop awhile and watch. Remember to take your camera.

References:

Bull, John and John Farrand, Jr. National Audubon Society Field Guide to North American Birds: Eastern Edition. NY, NY: Alfred A. Knopf, Inc., 1994.

Carpenter, Tom. The Gardener's Bird Book. Minnetonka, MN: National Home Gardening Club, 1999.

Cornell Lab of Ornithology: All About Birds. Blue Grosbeak.