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.

White-breasted Hawk

adult male White-breasted Hawk, Honduras, December 2011

White-breasted Hawk is a little known raptor from the Central American pine-oak forest. Officially (AOU) still a subspecies of the Sharp-shinned Hawk, most authors agree that this form should really be its own species. Currently, ten subspecies of Sharp-shinned Hawk (Accipiter striatus) are recognized, which can be subdivided in three main groups: the striatus (Sharp-shinned) group which contains four subspecies on the North American mainland and three island ssp; the Central American chionogaster (White-breasted) group with just one subspecies; and the erythronemius (Rufous-thighed) group with two South American subspecies (Bildstein & Meyer 2000). Future DNA work is likely to result in a split into at least three species: Sharp-shinned Hawk; White-breasted Hawk; and Rufous-thighed Hawk.

tail of adult male White-breasted Hawk, Honduras, December 2011

We caught this adult male while banding in Monte Uyuca (Honduras) last week. We have been banding there every month for two years now, and regularly see White-breasted Hawks around the net lanes. This was the first time we caught it here. Note (browner) retained outer rectrices from a previous molt generation.

Upperside wing ad male White-breasted Hawk, Honduras, December 2011

Upperside wing shot. Note the difference in (browner) retained primary coverts compared to (slaty) fresher secondary coverts.

adult male White-breasted Hawk, Honduras, December 2011

After we released the bird, it perched in a nearby tree. It may be worth noting that the tibial feathers appear white, like the rest of the underparts. Bildstein & Meyer (2000) describe light ochraceous-buff tibial feathering for the adult White-breasted Hawk...

juvenile male Sharp-shinned Hawk, Honduras, December 2011

Another first for the site was this juvenile male Sharp-shinned Hawk. We caught it two days later during the same pulse.

juvenile male Sharp-shinned Hawk, Honduras, December 2011

White-breasted Hawk is a resident species here in Honduras; Sharp-shinned Hawk is a winter visitor to the region.

References
Bildstein, Keith L. and Ken Meyer. 2000. Sharp-shinned Hawk (Accipiter striatus), 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/482

A Prairie Merlin in Honduras

Adult male Prairie Merlin, Campus Zamorano University, Honduras, 18 December 2011

Yesterday, while birding the Zamorano University campus in central Honduras with Paul Stufkens, my friend Oliver and I found an adult male Merlin of the Richardson's or prairie subspecies. The Global Raptor Information Network (GRIN) calls the Merlin an "uncommon migrant and rare winter visitor (columbarius) in the lowlands of both coasts and in the Caribbean islands off Honduras", citing Monroe's 1968 Distributional Survey of the Birds of Honduras. eBird has few records for this species in Honduras, although I suspect that Merlins are probably regular along both coasts in migration and perhaps uncommon, but not rare, in winter.

But a Prairie Merlin this far south is spectacular!

Merlin, a species found in North America, Europe and Asia, has three distinct populations in North America: the highly migratory Taiga Merlin (columbarius) of the northern forests, the sedentary Black Merlin (suckleyi) from the Pacific Northwest, and the partially migratory Prairie Merlin (richardsonii) of northern prairies and aspen parkland. The latter form winters from extreme southern Alberta and Saskatchewan southward to the area bounded by eastern California, northwestern Mexico and central Texas (James et al. 1987). Thus, it is resident in parts of its breeding range, with the majority undertaking a relatively short migration into the southern Great Plains (Temple 1972).

It is much paler overall than the taiga Merlin, and has the light bands on the tail much wider than in that subspecies.

I realized this was a noteworthy sighting, and I expected our Central American record of this subspecies to be perhaps unprecedented, but it turns out that eBird has a record for northern Belize - from just 5 days prior! On 13 December 2011, Lee Jones and Roni Martínez reported a female or juvenile of the prairie subspecies in northern Belize, noting it was significantly paler than the taiga Merlins these observers normally see in Belize.

records of Prairie Merlin in eBird (recent records in red) - data courtesy of eBird

So... these two recent records beg the question: Is there currently a small-scale influx of Prairie Merlins going on into Mexico and Central America? It will be interesting to see if more individuals of this subspecies get reported in the coming weeks from the region.

Cited literature:
James, Paul C., Alan R. Smith, Lynn W. Oliphant, Ian G. Warkentin (1987) "Northward expansion of the wintering range of Richardson's Merlin" Journal of Field Ornithology 58 (2): 112—117.
Temple, Stanley A. (1972) "Systematics and evolution of the North American Merlins" The Auk 89: 325—338.

Photo contest

Laughing Falcon - photo Perla Damara

Some weeks ago, I decided to organize a photo contest, with my camera as the prize! Several crew members of the Veracruz River of Raptors project had expressed an interest in buying my camera, and I felt that selling it to one of them would leave others disappointed. Personally, I had been toying for a while with the idea of birding without a camera altogether. I felt that wanting to photograph a bird often got in the way of observing it, and more than one encounter with an interesting bird resulted in a couple of poor quality shots, when I could have had great views.

Thus, the idea for the contest was born. I'll be birding without a camera for a while, and will likely be blogging less also.

All VRR count crew members and the educational interns were eligible for participation, and many liked the idea well enough to take a day to go out in the field and document good birds. Anything could be photographed, but it was understood that a great photo of a very common, easily photographed bird was not going to win against an equally great photo of a rarer or more secretive bird. The idea was that all participants and myself would vote, and that you could not vote for your own photo.

Well, the voting part got curtailed by my sickness (food poisoning) the last few days, but the winner was obvious to everyone. So, I proudly present on this blog some of the entries in this competition.

Incidentally, the camera in question is a Canon PowerShot FZ-20.

The winning photo at the top of a Laughing Falcon was made by Perla, who worked on environmental education this season (and did a great job). Laughing Falcon is not a particularly rare species in central Veracruz, but like most raptors it is not so easily photographed when perched. She had many photos of this individual, from many different angles; it was clear that she had spent time thinking how to best capture the bird. Perla surprised us with great photos of other species also. She came into the project knowing little about birding, but quickly learned a great deal. I hope that she will continue to go out in the field and document her sightings, and maybe get hooked on birding. Mexico is a great place to live as a birder.

The other photos are in no particular order.

Vermilion Flycatcher - photo by Roberto Rodriguez

This photo of a Vermilion Flycatcher is also a treat. Roberto must have been very close to the bird when he took it. Again, there were many shots of this individual, some even showing behaviors like preening. My impression is that this species is an uncommon breeder in the area, but becomes much more common from early November on, when the local population is augmented by winter visitors from the north. Even on a dull day, the vermilion of the male is dashing, attractive.

Sharp-shinned Hawk and Ferruginous Pygmy Owl - photo by Rigoberto Mendoza

This is a completely different type of photography. Here, the photographer had to act very fast while the story developed. What happened was this: we were sitting on the lower level deck of the Chichicaxtle observation tower when an adult female Sharp-shinned Hawk suddenly came wheezing out of the sky with landing gear out, to try and grab a Ferruginous Pygmy Owl perched in a tree in front of us. A brief pursuit ended on the ground with the owl screaming, wings held open, and the sharpie trying to approach it, also with wings open. The cries of the owl attracted a Merlin, who came in to inspect what was going on. The owl took advantage of this brief distraction and escaped; in the end, the attack was unsuccessful. It may be worth mentioning that the BNA account for Sharp-shinned Hawk lists as known avian prey items members from the orders of Passeriformes (the majority), Falconiformes, Galliformes, Charadriiformes, Columbiformes, Apodiformes, and Piciformes - but not from Strigiformes (owls)! A unique opportunity where the photographer did not have any time to worry about proper camera settings, composition etc, and just had to document the action in front of him. Well done, I think.

Blue-gray Gnatcatcher - photo by Jeniffer Abrego

Jeni captured a very common winter visitor to the area, Blue-gray Gnatcatcher. This bird seems to be intently studying the substrate for possible prey items, seemingly oblivious to the photographer nearby. Maybe not a difficult species to photograph, I still like this photo for the way it captures a bird actively foraging.

Black Vulture with Turkey Vultures - photo by Lynn Schofield

Lynn said she wanted to photograph vultures. Her objective was to document a behavior rather than a rare bird. So here the Turkey Vultures timidly walking away while the Black Vulture unashamedly continues to gorge on the rotting fish creates the dramatic tension she was looking for.

Willet - photo by Alfredo Beltran

Alfredo was unlucky with the weather. He was one of the first and most enthusiastic contestants, but had the camera on a day when taking anything worthwhile was going to be difficult. Secretly I kinda wanted him to win the contest. Alfredo is a very funny, likeable kid. He's got a hat that reads "My Life is a Gamble" and sometimes it seemed that way, with him drawing the shorter of the two straws.

Ruddy Ducks - photo by Irving Chavez and Pilar González

Irving and Pilar chose to capture moving subjects, always more difficult than a stationary bird. Practically everything is in focus, up to the splashes of water flying around. In the same lagoon, they found a mega rarity - Common Loon - which they dutifully photo-documented and reported to eBird, but the shot of the ruddies taking off was the better photo.

Double-striped Thick-knee - photo by John van Dort

This is one of the last shots I took with that camera. We found these birds to be abundant in a stretch of dunes close to Playa Juan Angel. Had I known about this, I would have told our Dutch visitors, for this was one of their target birds, and I don't think they found any.

I'm not planning to give up birding altogether, but I'll be birding without a camera for a while. I may end up blogging less, or perhaps I'll just work on improving the static pages of this blog. I'm going to play it by ear a little bit.

Veracruz season wrap-up

Broad-winged Hawks, Turkey Vultures and Swainson's Hawks disappearing into a cloud

The Veracruz River of Raptors 2011 season ended 20 November. The total number of raptors counted - nearly 4.5 million - was about average, but that figure hides several surprises this season. Mississippi Kite (324,488), Northern Harrier (872), Peregrine Falcon (1,011) and American Kestrel (5,326) all had their best season ever, as did the two accipiters, Sharp-shinned (3,958) and Cooper's Hawk (2,693). The Red-shouldered Hawk with a season's total of 15 tied with 2009's total for best ever. The Hook-billed Kite count on the other hand ended up as the lowest of the last nine years.

Eagles were again seen this season, and surprisingly early: a Bald Eagle on the first of September, and a Golden Eagle on the 13th of September, followed by another Golden 6 days later. Not surprisingly, I did not see any of these eagles. This was my third year in this project and I am one of the very few if not only counters who has never seen an eagle in Veracruz. I did pick up a Ferruginous Hawk, though.

Of the four bulk species that together make up 99.9% of the flight,  i.e. Mississippi Kite, Broad-winged Hawk, Swainson's Hawk and Turkey Vulture, only the first did well. The other three had average years - the Swainson's Hawk actually a little below average.

The Zone-tailed Hawk flight was early this year, and was well under way by September, with good flights on September 7 (20), Sep 18 (22) and Sep 23 (12). October, however, was disappointing, with only 44 zonetails counted.

Count-wise, a couple of things were different this year. In Cardel, we counted from the roof of Hotel Estación - not from the famous Bienvenido, which had construction going on this fall. Another difference with previous years perhaps was the lack of tour groups visiting the count. Recent media reports of drug violence in the state of Veracruz kept away virtually all visitors from the US. Instead, we had international visitors from Holland, some of whom (Leo, Dick) diligently scoped through the lines and helped us find birds for nearly a month. They were great company, and everyone in the group enjoyed their company. Was their presence beneficial to the count? Quite possibly.

Still, the high counts to me seem real, not a product of increased observer effort. The Mississippi Kite flight for example was more or less counted by the time Leo and Dick showed up. The exceptional Northern Harrier count also was real, as evidenced by extraordinary numbers caught by the Pronatura VRR banding operation, not far from the count site. They caught nearly forty harriers, when only one or two is normal for a season's worth of banding. The nearest hawk count site, the Corpus Christi count site in southern Texas, had their second best harrier season ever. They also had their best and second-best seasons for Sharp-shinned and Cooper's Hawks respectively. Like us, they counted more American Kestrels this year than any other year. Their Peregrine Falcon numbers, however, were not any higher than usual.

Non raptorial highlights this year included a Sandhill Crane on October 4 in Chichicaxtle, a Chihuahuan Raven on October 27 in Cardel, and a couple of Yellow-headed Blackbirds on November 4 in Chichicaxtle. A group of birders from the project led by Irving Chavez Dominguez found a Common Loon on nearby lagoon La Mancha on November 13, a bird that was still present at least 5 days later.