Tuesday, October 29, 2013

Prairie Merlin: overlooked in Central America?

Sunday morning, I photographed this female or immature Prairie Merlin (Falco columbarius richardsonii) behind our house, on a dirt road that leads to the top of Cerro de Hula. In this plumage they are similar to Taiga Merlins (ssp columbarius), the expected ssp in Central America, but subtly differ in the following aspects: paler overall; rufousy thin breast streaks on a white breast; malar stripe nearly absent; paler mantle. The overcast weather made for a very dark photo. In the field, the bird looked pale.

Two years ago, there was an adult male on the campus of Zamorano University, about 27 km from Cerro de Hula. The weather was about the same that day, i.e. overcast and drizzly, but adult males are a little easier to identify. See this blog entry for a detailed description and photos of that observation, and for a discussion of the regional occurrence of the various Merlin subspecies.

There’s one other record on eBird for the region, from Belize two years ago. That bird was photographed only after it had flown further away from the observers. Although the photo apparently was too distant to be conclusive, the description is convincing. Interestingly, that observation was 5 days apart from ours in Zamorano. The Zamorano bird was not seen again that winter, despite regular coverage. I wonder if our Cerro de Hula bird will stick around.

Prairie Merlins are thought to winter no further south than northwest Mexico, but these reports indicate that small numbers may winter further south than previously thought.

Saturday, October 19, 2013

Cool yard bird: Black-billed Cuckoo

Lately, I have had cuckoos on my mind. There was a week or so last year when you couldn't bird just about anywhere in central Honduras without seeing at least one of the Coccyzus cuckoos – usually the more common Yellow-billed Cuckoo. But that was late September / early October, and after mid-October this year, I thought the window was closing on them, and I wasn't going to see one this year.

Then suddenly there was this hatch-year Black-billed Cuckoo in my own backyard this morning! Probably not a rarity in Honduras, where the entire North American population must pass through in migration twice a year, but all the same a species rarely reported, due to its secretive habits.

Now I need to find me a Yellow-billed Cuckoo.

27 October 2013 postscript:
Eight days later and 200 m further, Roselvy and I found an immature Black-billed Cuckoo today! According to eBird, nobody else is reporting this species in Central America this fall, and here we are with two immature Black-billed Cuckoos. Are they the same bird? It seems likely, yet I'm not 100% convinced that they are. Here are some photos of today's bird, seen along the dirt road that goes up to Cerro de Hula (Honduras). As I said, this is roughly 200 m from our backyard.

We're looking at the other side of the face, compared to last week's bird. But note the distribution of the darker color on the (lower) mandible. Here's a photo in which the bird turned its head:

Compare that to the bird at the top of this post, and tell me if it's the same bird or not.

I never did find that Yellow-billed Cuckoo...

Friday, October 11, 2013

Raptor migration in the Gulf of Fonseca

Swainson's Hawks migrating over San Lorenzo, Valle
Exactly one year ago, on 10 October 2012, I observed a large raptor flight in San Lorenzo, Valle. Thinking the same phenomenon would likely be visible at the same location a year later, Roselvy and I went down to the southern lowlands yesterday, where we visited the same site, and a few nearby birding spots.

Sure enough, when we got there, we found a sizable raptor flight in progress. Like last year, the flight consisted mostly of Turkey Vultures and Swainson's Hawks, with modest numbers of Broad-winged Hawks and a smattering of other species present. Unlike last year, most lines were far away from the salt ponds complex La Ostia, where we started our birding, so there we focused on the shorebirds present.

Wilson's Plovers
Those too were nearly the same species and number as last year! Last year I missed Stilt Sandpiper – yesterday two were present; and I missed (western) Willet – yesterday three were present. We missed Solitary Sandpiper yesterday, but apart from those differences, we observed the same species in more or less the same numbers as exactly one year ago.

Stilt Sandpipers
After an hour and forty-five minutes in oppressive midday heat, we bailed and looked for food, shade and a better view of the raptor flight at Restaurante Brisas del Golfo. There we observed a raptor line directly overhead, one further south crossing the Gulf, and one further inland over the hills. Although we didn't count, we estimated about 10,000 Turkey Vultures, 6,000 Swainson's Hawks and 500 Broad-winged Hawks to have been passing us during the one hour and forty-five minutes we spent there.

Swainson's Hawks
A final stop at nearby shrimp farm Culmavic added migrant Chimney Swift and American Kestrel to our list, as well as the locally common Clapper Rail.

Tuesday, September 17, 2013

More small hummingbirds

Bumblebee Hummingbird
Very similar to the Wine-throated Hummingbird of the previous entry is Bumblebee Hummingbird, which replaces it north of the Isthmus of Tehuantepec. I myself went north of the Isthmus of Tehuantepec last week, on a business trip quite similar to the one I undertook in March of this year. This time I visited the Veracruz River of Raptors project, a project I worked for in 2008, 2009 and 2011. I got one day of birding in the pine-oak forests of La Joya in, just west of Xalapa. Bumblebee Hummingbird is locally common there.

Unlike the male Wine-throated Hummingbird, which perches conspicuously and vocalizes constantly, flashing his brilliant gorget in all directions, the male Bumblebee Hummingbird is more low-key, and apparently perches inside the vegetation, where it was difficult to find. Every once in a while, a conspecific would fly by and mouse-like squeaks emanated from the vegetation, while the producer of those squeaks remained invisible. They were more easily seen when feeding, moving slowly but constantly like a bumblebee from flower to flower.

Sparkling-tailed Hummingbird
A similar feeding style is seen in Sparkling-tailed Hummingbird. This morning I photographed this female as it fed quietly in a flowerbed on the top of Cerro de Hula (Honduras).

Monday, September 2, 2013

Wine-throated Hummingbird

Many migratory birds that breed in the United States and Canada have finished breeding and have started to show up in Honduras recently. Many residents have also finished their breeding season, and juveniles of those species which retain a juvenal plumage for a while (like Rusty Sparrow, Eastern Bluebird and Bushy-crested Jay, to name a few) now seem to be everywhere.

For one group of residents – the nectarivores – the breeding season is just starting here in Honduras. Both hummingbirds and flowerpiercers are easily found these days, because many of them are quite vocal and active. Some species, like the Wine-throated Hummingbird pictured above, spend much of their time displaying at leks, and produce an endless series of chips when perched on a favorite branch, or a surprisingly musical song when hovering in front of a female. 

While chirping from an exposed perch, the male often puffs up his extravagant gorget, which glitters bright magenta from some angles, but shows a duller green or a dark wine-red from other angles.  

Posturing also forms part of the display of this species. Every once in a while, whenever a conspecific flew past (my feeling was males mostly, but I'm not 100% sure), the displaying perched male would spread his tail and raise his wings, but remain perched, apparently to impress another male, or perhaps to impress the watching female.

We observed these Wine-throated Hummingbirds in La Tigra National Park, near Tegucigalpa, last Saturday. While hummingbirds and flowerpiercers can be hard to find at times, their songs are now frequently heard, and watching their displays is fascinating. We also observed several male Green-breasted Mountain-gems dueling fiercely in mid-air.