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While checking the Pajareros bird forum, where rare bird sightings in Costa Rica get posted, I was blown away by the latest post (December 16, 2008). In that post are digiscoped images of Gray-bellied Goshawk (Accipiter poliogaster) from La Selva. Although Costa Rica could still get some new species for the country list, this was one I never expected! This is a little-known South American species rarely seen even in its known range. Amongst neotropical ornithophiles and raptor lovers, it is most well known for exhibiting juvenile plumage that mimics adult Ornate Hawk Eagle. Check out the Pajareros post to see how incredibally similar it resembles Ornate Hawk Eagle. The main differences to separate it from the Hawk Eagle aside from size (the Hawk is smaller) are:

1. Structure- lack of pointed crest,

2. Black malar goes up to black crown behind the eye instead of going through the eye. I realize this sounds confusing- post mentions this and is apparent when comparing images of both species.

3. More spotted affect below rather than barred.

4. White edging to feathers on upperparts.

5. Bare thighs- often hard to see.

6. Juveniles often give a high-pitched call over and over.

Most of these marks are shown by the bird in the image which also resembles the only Gray-bellied Goshawk I have seen. That was a juvie. in Tambopata, Peru (Posada Amazonas) around the same time of year, 2004. This was a new species for that area as well. I especially recall the more spotted appearance of the underparts, white edging on the upperparts, black stripe on the face behind the eye and (like other juv. raptors) very easy to see. It sat all day at the top of the same tree ( conveniently near a canopy tower) and called over and over a short high-pitched descending call.

Gray-bellied Goshawk species is known to be a partial austral migrant; this juv. must have gotten lost somewhere between here and Argentina. Hard to say where it came from exactly; especially because this species is probably wider ranging than thought since neotropical forest Accipiters are very infrequently seen. It is interesting to note that the poster at the forum mentions that he saw one in the Darien, Panama. Who knows- it might even occur there or in the Choco (western Columbia and NW Ecuador) on a regular basis.

Hopefully this bird will stick around for the La Selva Christmas Count on Saturday!

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One Response to “Incredible new species for the Costa Rica list; Gray-bellied Goshawk!”

  1. Hello and pura vida,

    Excellent reccord the GB Grosshawk for Costa Rica!!!!
    I just posted a picture of this species seen in Cristalino Lodge, SouthernAmazon from a Canopy Tower.
    I will let you know about theyr prey as soon as discover it.
    Loads of Red-and-green macaw around there, allways extreamely excited with the presence of this hawk-eagle

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