Survey Finds Rare Hummer in New Areas, Locates First Ever Nests, Identifies Females

Esmeraldas Woodstar. Photo: Jose Ilanes, Tropical Birding

The results of an American Bird Conservancy-funded study of the distribution and nesting of the globally endangered Esmeraldas Woodstar have just been released by Fundación Jocotoco, with some encouraging news. This tiny hummingbird, barely bigger than a bumblebee, is endemic to the dry forests of the coastal mountains of central and northern Ecuador, where it has a tiny range and the lack of suitable habitat makes its distribution extremely fragmented.

Although the researchers encountered the hummingbird most frequently in the Ayampe area, they also found small numbers at sites as far as 62 miles northward along the coast. They also found the nest of the species for the first time ever. In fact, they located a total of 33 nests—a remarkable number for any species of tropical hummingbird. While monitoring these nests, the researchers discovered that birds previously described and shown in field guide illustrations as females were actually juvenile males. It is now known that female Esmeraldas Woodstars resemble the females of the closely related Little Woodstar, although with a distinct tail pattern and different head markings.

“In spite of these recent advances, the Esmeraldas Woodstar remains an elusive species,” said David Wiedenfeld, American Bird Conservancy’s Assistant Director of International Programs. “Most birds leave their breeding grounds after the nesting season is over, but it is still not fully understood where all of them go. Some may move higher into the mountains along the coast, or they may move inland to other forested areas. Future research may provide answers to this question, helping to advance conservation efforts for this diminutive bird.”