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.

1 comment:

Tom Jenner said...

Part of the problem is that it is so rare to get a good enough view to tell the difference. During my nine years in El Salvador I saw very few Merlins (maybe about 5 in total) and all of them were fly-bys. You did well to get that photo.