Migrant flycatchers
Fall migration is underway, and mid-August marks the time when the first Wood-Pewees (Contopus) and Empidonax flycatchers arrive in the region. These are two difficult groups for birders of all skill levels, and not all individuals encountered in the field will be identifiable. Silent birds that provide only brief views before disappearing into the vegetation are best left unidentified. It’s perfectly acceptable – indeed preferable – to leave them as Contopus sp. or Empidonax sp. on your eBird checklist!
However, given good views and the benefit of hearing the bird vocalize, it is often possible to make a confident identification based on a careful examination.
Helpful discussions of the identification challenges in each of these groups can be found in the online archives of Birding Magazine. Although a subscription-based magazine, some articles are offered free of charge. Click here to download a 2008 article on field identification of Western and Eastern Wood-Pewees by Cin-Ty Lee, Andrew Birch and Ted Lee Eubanks. Click here to download a 2009 article by Forrest Rowland on identifying Empidonax flycatchers.
It is worth noting that these articles were written for a birding audience in the United States and Canada. Thus, some empids are discussed that rarely if ever visit Central America (e.g. Dusky Flycatcher, Cordilleran Flycatcher and Pacific-slope Flycatcher). Likewise, some Central American resident members of these genera (e.g. Tropical Pewee, White-throated Flycatcher) are not mentioned in the North American context of those articles.
We encourage Central American birders to study the migrant flycatchers as well as the residents, and hope that the two resources mentioned above are useful. In-depth discussions of North American Empidonax identification challenges are also found in Kenn Kaufman’s excellent Field Guide to Advanced Birding. David Sibley’s blog features a good discussion of identifying Eastern vs. Western Wood-Pewee, here.
For the study of call notes, both Xeno-Canto and the Macaulay Library have useful reference material available.
Good birding!