Who Is “Swainson” and Why Are So Many Birds Named for Him?

Most birds are named for descriptive features – Red-tailed Hawk – but some are named for people. And some people, like William John Swainson, seem to have an inordinate number of birds named for them. Swainson’s Hawk, Swainson’s Thrush, Swainson’s Flycatcher, Swainson’s Warbler; the list goes on and on. Nine, in all.

Swainson is best remembered for the quality of his illustrations.

Swainson Illustration Gray-backed Warbler

Swainson Illustration of Gray-backed Warbler

Swainson Illustration Blue Nuthatch

Swainson Illustration of Blue Nuthatch

Swainson’s drawing style was influenced by John James Audubon, America’s first great ornithologist. Some of their correspondence can be found on-line.  Audubon’s meticulous detail and more fluid poses can be seen in Swainson’s drawings. Audubon rewarded his friend by naming a warbler species he had discovered, the Swainson’s Warbler, Limnothlypis swainsonii. (This is a U.S. Fish & Wildlife photo; WC has never seen a Swainson’s Warbler.)

Swainson's Warbler, Great Dismal Swamp National Wildlife Refuge. Credit: USFWS

Swainson’s Warbler, Great Dismal Swamp National Wildlife Refuge. Credit: USFWS

Charles Lucien Bonaparte, a Frenchman who did early ornithological work in the South America, after whom is named Bonaparte’s Gull, named a hawk species he had discovered after Swainson, the Swainson’s Hawk, Buteo Swainsonii, of course.

Swainson's Hawk, Camas Prairie, Idaho

Swainson’s Hawk, Camas Prairie, Idaho

Thomas Nuttall, an Englishman who also did early ornithological work in America, after whom is named Nuttall’s Woodpecker, named a thrush he discovered after Swanson, Swainson’s Thrush, Catharus ustulatus.

Swainson's Thrush, Creamer's Refuge, Fairbanks, Alaska

Swainson’s Thrush, Creamer’s Refuge, Fairbanks, Alaska

WC hasn’t been able to determine who named a fairly common South American flycatcher after Swaison; its extremely unlikely it was Swainson himself. But there is a Swainson’s Flycatcher.

Swainson's Flycatcher, Pantanal, Brazil

Swainson’s Flycatcher, Pantanal, Brazil

In all there are at least nine species of birds named for William Swainson. Which is kind of odd, because while he was a fine illustrator and produced some of the very best early published works on North American birds, as a scientist he was kind of a hack. Swainson was an enthusiastic supporter of the ideas of the Quinarian system of biological classification.1 The Quirnian system was nonsense. Swainson, along with another Quirnian supporter,  William Sharp Macleay, were scorned for their ideas and Swainson moved to New Zealand. His science there didn’t get any better, but that’s beyond the scope of this blog post.

So, to answer the question, William Swainson was a Brit who visited North America and did some early work getting specimens and writing illustrated books about those birds. His work was admired enough by Audubon, Nuttall and Bonaparte that they named species they discovered after him, as was common back in the day. Swainson seems to have ended up with a lot more species than his professional work deserves, but there it is.


  1. Quirnian zoological classification was “numerology meets taxonomy.” It was based on the supposition that everything divided into five subgroups. The theory has the distinction being hooted down ever before publication. Charles Darwin’s Origin of Species and the idea of evolutionary trees demolished any plausibility Quirnians ever had.