Tuesday, January 24, 2012

eBirding Honduras

Cassin's Kingbird, Jan 23, 2012, Cerro de Hula, Honduras
eBird, an online database for bird observations launched in 2002 by Cornell University and National Audubon Society, now routinely logs over a million bird observations each month!

The vast majority of those sightings are of course from the United States and southern Canada. Certain localities - the more populated areas on both coasts - receive ample coverage.

Recently, eBird asked its community of birders to make an effort and contribute checklists from 'under-birded' areas, typically areas where fewer birders live.

The other day, upon hearing I was now in Honduras for a whole year, a friend of mine from Massachusetts asked me whether I was eBirding down here at all.

"All the time!" I said. (According to eBird, I've submitted 26 checklists so far this month.)

Not surprisingly, Honduras is a seriously under-birded country. Very few birders live here, and few birders visit (compared to countries like Costa Rica, Panama and Belize, or even Guatemala or Mexico). Thus, it is not unusual to find birds here that have few or no Honduran reports in eBird. Here's a sample from just the last few days:

Ash-throated Flycatcher, Jan 22, 2012, Los Noques, Honduras
Sunday, Roselvy and I went to a nearby valley, where we encountered an Ash-throated Flycatcher, a species rarely reported this far south. Other Myiarchus flycatchers, like Dusky-capped, Brown-crested, Nutting's, or Great Crested, are more frequently observed.

eBird records for Ash-throated Flycatcher in Central America as per Jan 24, 2012 (data courtesy of ebird.org)
The only other Central American record of Ash-throated in eBird is from a 2004 checklist submitted from Nicaragua (species crossed off as 'present', without further details).

Ring-necked Ducks, Jan 22, 2012, Los Noques, Honduras
Also Sunday, at the same place, we found a group of 12 Ring-necked Ducks (a male and two females pictured above).

eBird records for Ring-necked Duck in Central America as per Jan 24, 2012 (data courtesy of ebird.org)
The only other Honduran record in eBird for this species is from 2008, Lake Yojoa, where 4 individuals were seen. Our Ring-necked Ducks were in company of two female Lesser Scaup, a more expected species in Central America.

Ruddy Duck, Jan 22, 2012, Los Noques, Honduras
Ruddy Duck is also rare in Honduras. eBird has one other record, 10 individuals seen in 2008.

Cassin's Kingbird, Jan 23, 2012, Cerro de Hula, Honduras
Cassin's Kingbird is probably rare almost anywhere in Central America.

eBird records for Cassin's Kingbird in Central America as per Jan 24, 2012 (data courtesy of ebird.org)
There's a January 2010 record from Nicaragua in eBird, but that's it. The bird we found yesterday in Cerro de Hula could not be relocated today.

Each bird mentioned above we found within a radius of 10 minutes driving time from our house, in unprotected areas. While doing point counts today (at only 3 minutes from our house), we saw or heard several Sedge Wrens, many Grasshopper Sparrows, four Wilson's Snipe... all birds that are infrequently reported in Honduras.

This begs the question whether all these birds are genuinely rare in the region, or have simply been overlooked. Over time, eBird will provide the answer.

Sunday, January 8, 2012

Plumbeous Vireo

Last week, Roselvy and I moved into our new house in Santa Ana, in the department of Francisco Morazan, Honduras, where we will be working with birds for an entire year. We already love it here, with lots of cool birds in the surrounding pine-oak forests.

One notable member of the bird community here is a Central American subspecies of Plumbeous Vireo.

Plumbeous Vireo became its own species in 1997, when the AOU split the Solitary Vireo into three species: Cassin's, Plumbeous and Blue-headed Vireo. All three are field-identifiable, with the most western Cassin's Vireo of California, Oregon, Washington and southern British Columbia more or less intermediate in appearance between the drab gray Plumbeous Vireo of the Intermountain West and the more colorful Blue-headed Vireo of the northeastern and boreal forest.

The Central American subspecies of the Plumbeous Vireo found in El Salvador and Honduras is actually more similar to Cassin's Vireo than it is to northern Plumbeous Vireo populations. Currently, the two subspecies recognized in Central America are notius (Belize) and montanus (El Salvador and Honduras), although these subspecies sometimes have been considered synonymous (Curson & Goguen 1998). Monroe (1968) considered the Honduran subspecies to be notius rather than montanus.

In this subspecies, the sides of the breast and belly are greenish (not gray), the secondaries have greenish edges (not gray), and there is a subtle contrast between the blueish gray head and the greenish gray back, unlike the all-gray head and back of the northern Plumbeous Vireo.

The vocalizations are different too. Here's some footage of a bird calling in response to my Ferruginous Pygmy-Owl imitation.

I also recorded some song. The same individual first sang a more or less continuous song, followed by a different song consisting of shorter, more hesitant phrases.

Cited literature
Curson, David R. and Christopher B. Goguen. 1998. Plumbeous Vireo (Vireo plumbeus), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/366
Monroe, Jr., B. L. 1968. A distributional survey of the birds of Honduras. Ornithol. Monogr. 7.