Sunday, December 29, 2019

Limpkin's rare journey from Florida to Ohio causes stir among bird watchers

A limpkin with freshly caught snail at Ottawa National Wildlife Refuge/Jim McCormac

Limpkin's rare journey from Florida to Ohio causes stir among bird watchers

December 29, 2019

NATURE
Jim McCormac

An amazing report crackled through the birding grapevine on July 6.

A limpkin was found at a small suburban pond in Orville in Wayne County. Birders fortunate enough to reach the site in time found it. Come dusk, the wayward oddity, which looks like a cross between a heron and a rail, flew into a nearby tree to roost for the night.

Many birders were on-site at the crack of dawn the following morning, myself among them. Alas, the limpkin had flown the coop. We searched likely habitats nearby, but no one could find the bird.

Why the excitement? In the U.S., the limpkin is known as a Florida specialty, rarely seen away from the Sunshine State. That is the northern limit of its breeding range. Limpkins occur south through the Caribbean, Mexico and Central America, and into South America.

Limpkins are largely nonmigratory, and records north of Florida are few. Most vagrants turn up in southeastern states near Florida: Georgia, the Carolinas, with a handful of Maryland and Virginia records. Astonishing is a trio of old reports from the Canadian province of Nova Scotia.

The same day the Orville limpkin was discovered, an after-the fact report came in via new birder Nannette Patrick. She found and photographed a limpkin near Mentor, east of Cleveland, on July 3. Then, in mid-October, longtime birder John Pogacnik found yet another limpkin in the same region.

In between the Mentor records, a limpkin appeared at Magee Marsh Wildlife Area east of Toledo. That bird stayed through fall and was widely seen. By October, the Magee limpkin was getting harder to find, until it appeared at the adjacent Ottawa National Wildlife Refuge on Nov. 16.

I visited the Ottawa limpkin on Nov. 18. It was a snap to find. Seemingly unafraid, it went about its business of capturing snails in a small patch of swamp woods. In between hunting escargot, it would rest and preen in close proximity to a small knot of fawning birders.

If all of these records pertain to different individuals, it would constitute a mini-invasion of four birds, in a state where none had ever been recorded. Furthermore, they represent the farthest north the species has been seen in the U.S. Another limpkin turned up in southeastern Illinois — the only other Midwestern record.

Limpkins feed almost exclusively on snails, and to a lesser extent small mussels, and in Florida and points south they favor large apple snails. The Ottawa bird also fed on aquatic snails, but a smaller species, perhaps in the genus Stagnicola. It was adept at finding them, and in a half-hour period, I watched it capture and eat more than a dozen.

What would prompt such an unprecedented northward movement of a largely sedentary southern bird? Perhaps the best explanation is linked to a tremendous limpkin population expansion in Florida in recent years.

The limpkin population was perhaps constrained by its preferred food, the native Florida apple snail. In the past decade, populations of at least four species of nonnative apple snails have flourished. Opportunistic limpkins took a shine to this new food source, and their numbers have skyrocketed.

A limpkin boom means more birds to wander. These “scouts” that turn up in far-flung regions might perish, as they presumably do not have migratory roadmaps hardwired into their DNA. But over time, it is likely that new populations will become established north of the current home range.

The only certainty with bird populations is change.

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.


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