[AlexC]

Discussion thread for White-breasted Hawk. If you would like to add a comment, click the Post Reply button.

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Considered a subspecies of "A. striatus" by both Clements and H&M. It may be just a matter of published data until it is split, but until then we should keep it with Sharp-shinned.

SACC:

Accipiter striatus was treated as four species in Sibley & Monroe (1990), Thiollay (1994), and Ridgely & Greenfield (2001): velox of N. America, chionogaster of Middle America, ventralis of the Andes, erythronemius of lowland southern South America); Pinto (1938) and Hellmayr & Conover (1949) considered erythronemius (including ventralis) to be a separate species from A. striatus, and Friedmann (1950) and Stiles & Skutch (1989) considered chionogaster and erythronemius as separate species from A. striatus. [split almost certainly good, but no published data support this split; check Storer (1952). According to HBW account author Rob Bierregaard, through correspondence with Tom Schulenberg, no published data support this split and he was basically forced to comply with species taxonomy given to him.] Ferguson-Lees & Christie (2001) did not follow this split and provided rationale against following it. Proposal needed.

I marked the article for "merging" as it is quite full of information.

[tomjenner]

All of the field guides to the region split it from Sharp-shin. Fergusen-Lees and Christie lumped the whole sharp-shin complex, but then split it in their later field guide. The only paper that really tackles the issue is issue is Storer (Condor: 1952). However, his entire arguement is based on the fact that there is a cline in underpart colouration of sharp-shins as you go further south in Mexico, leading to White-breasted Hawk. However, there is also north south cline with Sharp-shins increasing in size, yet White-breasted Hawk is smaller. There are also a number of other major differences between the southern form of Sharp-shin (madrensis) and White-breasted Hawk (chionogaster), such as iris colour differences of adults, the barred (albeit feint) undreparts and thighs of madrensis, compared to the unbarred underparts of chionogaster, the pale grey upperparts of madrensis compared to the dark grey almost black upperparts of chionogaster.
recent publications of the South American forms have treated them as a species and it seems to be just a matter of time before the split is accepted by the AOU.

Tom

[njlarsen]

I think the appropriate manner for Opus to deal with this would be to keep the entry, labeled with Alex's "merge" flag, but not give the merging any high priority; there are so many other things, such as making sure we have categories for all genera, so that the actual merging can wait.

Niels