Blue Grosbeak

 

A male Blue Grosbeak (Passerina caerulea) atop his singing perch, a sprig of Yellow Sweet Clover. This impossibly good-looking bird is much easier to find in Ohio than it once was. During Ohio's first breeding bird atlas (1982-87) this was a rare bird found sparingly in our southernmost counties. Since then, the population has grown by nearly 12% annually and Blue Grosbeaks can be found routinely to Lake Erie. A colorful Exhibit A of a recent range expansion of a southern species. This one was in Franklin County, and I photographed it on June 4, 2023. I'm going to soon write a more in-depth piece on Blue Grosbeaks and their continuing northward range expansion for my Columbus Dispatch newspaper column and will post that here after it runs.

Blue Grosbeak

A Blue Grosbeak (Passerina caerulea) sings on a nippy 36 F morning. Yesterday morning I stopped by a Ross County site where I've seen this species in year's past, and this male was immediately evident. Blue Grosbeaks deliver a distinctive rich warbling song, reminiscent of a Purple Finch. The vast majority of birds that I've found have alerted me to their presence by their song, which carries for quite some distance.

Probably due to the cold, he was foraging down low and even spent time on the ground. Here he poses on old stalks of Indian Grass in a prairie meadow. Henslow's Sparrows were singing nearby.

This southern species is expanding northward and is much easier to find - at least in Ohio - than in the not-too-distant past. When I was a kid, Blue Grosbeak was pretty much an Adams County specialty. Away from there, it was a great rarity. Not now.

During the first Ohio Breeding Bird Atlas (1982-87), Blue Grosbeak was found in only eleven counties, and was locally frequent in only Adams and Lawrence counties - two of our southernmost Ohio River counties. Their numbers and distribution had spiked by the time of Atlas II (2006-11). Surveyors found Blue Grosbeaks in nearly 70 counties and in much higher densities than occurred during the Atlas I period. Scattered pairs have made it all the way to the Lake Erie region, and it would not be especially surprising to turn one up anywhere in the state.

Blue Grosbeak numbers have skyrocketed in southern Ohio. Anywhere that their favored habitat of open meadows interspersed with scattered trees and brushy areas occurs, there is a great chance of finding this stunning relative of the Indigo Bunting.

Why are Blue Grosbeaks moving north and increasing in numbers? If one takes the long view, this species of semi-open country probably began its northward march following the opening up of the formerly vast eastern deciduous forest several centuries ago. Widespread clearing created much favorable habitat. However, that does not explain the fairly recent and obvious ongoing expansion. Forest clearing has been going on far longer than Blue Grosbeaks have been actively expanding northward, at least at the pace of the past few decades. This species clearly did not join in the boom-and-bust expansions of a trio of other open country songbirds in the late 19th and early to mid-20th centuries: Bachman's Sparrow, Bewick's Wren, and Loggerhead Shrike. Despite the apparent availability of suitable habitat, those three have crashed and the sparrow and wren are extirpated from the state. The shrike barely holds on. Yet the grosbeak is growing in numbers and conquering much new ground.

One big difference between the aforementioned shrike, sparrow, and wren and the Blue Grosbeak is that the latter is a Neotropical migrant, with nearly the entire population wintering in the Caribbean and especially in Central America. Ohio-nesting grosbeaks are traveling up to several thousand miles south to wintering grounds. The others were/are short-distance migrants or even year-round residents, wintering almost exclusively in the U.S. Who knows, perhaps upward shifts in mean temperatures is the catalyst for the northward sweep on grosbeaks. It will be interesting to watch their continued expansion.

Once rare, blue grosbeak sightings increase throughout Ohio

The blue grosbeak is expanding its range north.

COLUMBUS DISPATCH

July 3, 2016

NATURE

Jim McCormac

The blue grosbeak has long been a coveted bird in Ohio.

Until relatively recently, the best chance at seeing one was to cruise the back roads of rural Adams County, which is along the Ohio River between Cincinnati and Portsmouth. There, a bird-watcher might see this exotic songbird among unkempt pastures.

A male blue grosbeak is bedecked in rich cobalt feathering, punctuated by cinnamon wing bars. Its massive bill looks like it belongs on something else. The bird's song is a melodious warbling, as if the songs of a purple finch, indigo bunting and orchard oriole were fused into one.

Small wonder that those of an avian bent would want to view this bird.

In the early 1900s, naturalists eagerly reported Ohio blue grosbeak sightings. Perhaps the first indisputable sighting dates to 1925 in Lake County, when Edward Doolittle published a note about a bird he found in Painesville in the Wilson Bulletin.

Sightings were sparse until 1940, when ornithologist Lawrence Hicks found the first Ohio nest, in Adams County.

Adams County is a biological hot spot, well-known for hosting animals and plants rare or nonexistent elsewhere in the state, many at the northern limits of their ranges. Hicks’ inaugural grosbeak nesting was near the only established Ohio breeding locale for chuck-will’s-widow, which was discovered in 1932. This large nightjar is at its northern limits in Adams County.

By the 1980s, blue grosbeaks were obviously expanding north. Ohio sightings became more widespread and frequent. They could be expected in appropriate habitat in Ohio River counties from Cincinnati upriver to Gallipolis.

The expansion continues unabated, and now it would not be surprising to find a blue grosbeak anywhere, although southern Ohio remains the stronghold.

Birds appear annually as far north as the Oak Openings west of Toledo and routinely occur in central Ohio. Glacier Ridge Metro Park near Dublin hosted a singing male last summer.

The recently published Atlas of the Breeding Birds in Ohio (field work conducted from 2006 to '11) documented a 237 percent increase from the first atlas, which took place from 1982 to '87. Only seven other species showed greater increases between atlases.

Why the spike in blue grosbeaks? No one knows exactly, but it’s probably a combination of factors. This species favors open meadows interspersed with brushy fence rows and scattered trees, a habitat that greatly increased after the deforestation of much of Ohio. Steadily increasing mean temperatures may also be beneficial to this southern species.

Blue grosbeaks breed extensively across the southern United States and north in the Great Plains to the Dakotas. This highly migratory bird winters throughout Mexico and Central America.
Nonetheless, it is considered an uncommon species, and the North American population is estimated at 18 million birds; about one-fifth of that is its better-known relative, the indigo bunting.

Amazingly little is known of basic life history elements of the blue grosbeak. If someone with ornithological inclinations is looking for a master’s or doctoral thesis, this beautiful bunting would be a good candidate.

Naturalist Jim McCormac writes a column for The Dispatch on the first, third and fifth Sundays of the month. He also writes about nature at www.jimmccormac.blogspot.com.