Sooty Tern

Today, one the gardeners here at the Tortuguero Sea Turtle Conservancy handed me this bird, an adult Sooty Tern. He had found it in the water, unable to fly and just barely able to float, in the Tortuguero River near the river mouth.

I took the bird under my care and first made sure to dry it, as it was completely soaked. I checked for injuries but couldn't find any. The bird just seemed really exhausted, so I put it on a long-sleeve shirt in a carton box, and let it rest for a while. Three hours later, however, it was dead.

As I weighed it, and found that it only weighed 127 g, nearly half the weight of a healthy adult, I realized that it probably never had much of chance to begin with, poor thing.

Although globally one of the most abundant seabirds, in Costa Rica Sooty Tern is "a very rare visitor to Pacific coastal waters; no record yet for Caribbean coast" (Stiles & Skutch 1989). This is now outdated information (for example, there was a Tortuguero record last year, Pablo Elizondo pers. comm.) but the species certainly remains rare on the Caribbean coast. Heavy rains started last night and lasted until mid-morning; possibly this individual got disoriented in a nasty weather system.

Cited literature:
Stiles, F. G. and A. F. Skutch. 1989. A guide to the birds of Costa Rica. Cornell Univ. Press, Ithaca, NY.