Please join me in welcoming back our three birding Experts as they once again answer a birding question as submitted by our most excellent San Vito Bird Club members.
Jim Zook: Professional ornithologist, bird population specialist for Stanford University and co-author of ‘The Wildlife of Costa Rica‘. https://www.amazon.com/Wildlife-Costa-Rica-Tropical-Publications/dp/0801476100/ref=sr_1_1?dchild=1&qid=1595426723&refinements=p_27%3AJim+Zook&s=books&sr=1-1&text=Jim+Zook
Pepe Castiblanco: Co-owner and proprietor of Casa Botania B&B and professional birding and nature guide. https://www.casabotania.com/en-gb
David Rodriguez Arias: Tropical Biologist and natural history guide in Monteverde, Costa Rica. https://www.facebook.com/david.rodriguezarias
QUESTION #5: From SVBC member Vincent Albright; Hall’s Gap, Victoria in Australia.
‘On my previous two visits to Costa Rica I’ve been fascinated by the diversity of your Flycatchers. There are SO many different species! Can you provide some tips on how I can best learn to identify them?’
Pepe: If you were looking for the most diverse family of birds of America, stop. You found it. Flycatchers are fascinating birds that range from very local to long distance migrants. All of them eat insects, except for the ones who don’t! (bad joke). Despite their name, many had been the pressures that have split these birds in over 400 species across America, going from bright scarlet, to dull gray/brown, long crests and tails to tiny pigmy tyrants, true insect catchers to berry eaters.
So how can you ID them?
Insect eaters are very acrobatic and like to jump up in the air in pursuit of a fly. So they mostly perch on a bare branch or a place with visual advantage. Easier to spot since most of them have a yellow belly-breast and are dull brown or gray on the back. Great Kiskadees or Social Flycatchers are great example. Their color patterns and their blatant nature helps them find themselves or confirm if a perch is free or taken. Fruit eaters are more passive. Their prey is not going anywhere so you can find them among the foliage of fruiting trees like ficus, melastomes, rubiaceae family or berry bushes. A couple fruit eaters have long crests and tails like the Long-tailed Silky Flycatcher or the Yellow-bellied Elaenia. Their colors are also very subtle. Most blend with the foliage. The deeper you go in the forest, the harder it will get to find and ID them for they turn almost invisible to the inexperienced eye and their colors get dark green, gray, rusty and their size gets smaller and so their physical appearance also varies a lot. So you can have super specialized birds like the Bentbills, or the Todies. All insect eaters but filling a different niche and found at various levels of the forest.
Field guides and apps like Merlin are good companions to have but a local expert will be ideal to help you pick them out by call, habits or even bill shapes.
Below, a couple of extreme bill size differences between a Boat-billed Flycatcher and a Black-capped Flycatcher.
(photos courtesy of Pepe Castiblanco)
Jim: Yes, there are a bunch of flycatchers in Costa Rica. The Tyrannidae, or Tyrant Flycatchers (to distinguish them from Old World Flycatchers) is represented in Costa Rica by 81 species (mas o menos). Some of those are very rare species that have only been seen a few times here, others are migrants that are present only during the northern hemisphere winter or during migration, but at any one birding spot in the country one can expect to encounter regularly 10 to 20 different species – more if you include the rarer possibilities. One key is to know what the common species are in any given area, and learn to identify them well first. Then you’ll have a base for comparison and if you see something odd you can ask yourself “why isn’t this one of the common species?” Less common species are often associated with specific micro-habitats, so knowing what a species prefers is also important as in “that looks like a Yellow Tyrannulet, but those are only found in short, scrubby vegetation and we are in dense forest, so we can rule that out”. If you have to focus on one physical trait I’d say pay close attention to the bill – It’s length and width, color, and if bicolored the pattern, shape of bill tip (hooked or not), etc. But probably the best trick is to learn the vocalizations as that will be the key for separating those little green and gray birds that all look the same.
David: You’re right about the flycatchers diversity, in fact it is the most diverse family. It’s a new world family, which means that it is distributed only in the Americas. My recommendation is to observe the behavior; for example, flycatchers fly to try and catch an insect and then return to the same perch, making a loop. You can also learn the song and the call. When you’re fed up you catch them and analyze their features up close, because you when you catch them you can observe special characteristics on the primary and secondary feathers (I am talking about the Empidonax genus). You will understand that sometimes it is so difficult to identify them that you just give up and go to look for some other birds.
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