Red-shouldered Hawks in Florida...
... are quite common, and that points out one of the insidious problems with the eBird process of review of reports.
First, a digression.
The single most widespread problem with eBird is that eBirders are not required to understand how eBird works, what different sorts of entries mean, and what they include... or exclude, or, even, be able to reliably identify individual birds by sight and/or sound. Literally, anyone can report data to eBird and, so long as entries do not trip relevant filters, eBirders can report whatever they believe or, worse, whatever they want.
There is probably no more nearly invisibly pernicious effect on aspects of eBird caused by the ignorant eBirder than that engendered by eBird subspecies entries.
eBird subspecies entries -- that is, those subspecies or groups of similar subspecies for which eBird provides individual entry options -- are impenetrable for an apparently sizable number of eBirders. So long as the subspecies entry selected by the eBirder is not flagged as rare or if the observer does not report an unusually high number of individuals, eBirders can report their data to subspecies... without knowing anything about subspecies, what they are, and how they differ from other subspecies of the same species. This lack of knowledge by many is delineated well by Red-shouldered Hawks in Florida.
Florida is a fascinating biogeographical area, as so many bird species have differentiated at the subspecies level within Florida and in nearby portions of the southeastern US states and the Caribbean. This differentiation includes subspecies of such different species as Mottled Duck, Sandhill Crane, Red-tailed Hawk, Eastern Towhee, and Common and Boat-tailed grackles (and when will birders visiting Florida learn that Florida Boat-taileds have dark eyes, while the Common Grackles they know from elsewhere sport the pale eyes with which they are experienced).
Red-shouldered Hawk is one of the most taxonomically interesting Florida bird species as the state hosts two breeding subspecies (the southeast US alleni and the peninsular Florida endemic extimus) plus a third (lineatus) that arrives from the north as wintering individuals. eBird does make this situation at least a little simpler by combining alleni into the eBird subspecies group carrying the nominate subspecies name: lineatus, as in "Red-shouldered Hawk (lineatus group)." The east Texas subspecies texanus is also included in that group).
With both lineatus and alleni included in that subspecies group, northern Florida eBirders have little cause for concern or even thinking about Red-shouldered Hawk subspecies. However, from roughly the latitude of Orlando south, eBirders have two problems. The first is the virtually ignored difficulty of distinguishing either subspecies in its "pure" appearance from those individuals whose genetic makeup is a mix of both genomes. Yes, that is virtually an intractable problem... except that eBird provides nowhere I can readily find any direction about how eBirders should deal with subspecies entries... not that eBird would require reading such in order to be permitted to submit data to eBird. I mean, why worry about data quality and virtually undetectable incorrect identifications when observer numbers seem to be the end-all, be-all of eBird. More is better. Right?
This post's aim is to point out the discrepancy made obvious by eBird's treatment of Red-shouldered Hawk subspecies identifications in Florida. For the geographically limited extimus, extralimital reports virtually require sufficient photographic support to get a report validated of that subspecies from north of its known/expected range. However, with the arrival of northern migrants deep into peninsular Florida for the winter (see below), one need not actually prove reports of lineatus Group Red-shouldered Hawks within the permanent range of extimus. One certainly does not need photographic support and even if one has such support, the relevant eBird filters do not flag the entry for rarity, so one can expect one's photos of the reported occurrence to receive no scrutiny. I did not begin writing this blog post to test eBird. Instead, I thought I would review photos of reported instances of lineatus Group Red-shouldered Hawks within the permanent range of extimus.
Oh. My. Aching. Head.
Now for a second digression.
eBird included the southeastern Red-shouldered Hawk subspecies within the lineatus Group because it looks very similar to lineatus. The extimus subspecies is easily and demonstrably different due to its gray (nearly white in southernmost Florida) head; paler, duller underparts; and usually grayer back. In my personal experience in peninsular Florida, the gray or grayish head is one of the most obvious indicators of extimus genes, ignoring the undoubted widespread occurrence of intergrade Red-shouldereds in the peninsula in winter and which should not be reported to subspecies. These differences in plumage appearance between the two subspecies eBird entries are encapsulated in these photos:
lineatus Group -- Orange County
lineatus Group -- Palm Beach County (perhaps some small infusion of extimus genes)
extimus -- Charlotte County
extimus -- Monroe County
extimus -- Hendry County
Hopefully, no one would mistake this bird for a member of lineatus Group.
Had I known little or nothing of how eBird "develops" eBirders, I might have been quite surprised that so many of them providing photos of putative lineatus Group Red-shouldered Hawks seemed to know the differences between the two Florida-breeding subspecies of Red-shouldered Hawk. Unfortunately, I was not at all surprised and, with malice aforethought, targeted winter reports of lineatus Group Red-shouldereds within the range of extimus. In the below-linked checklist, the original identifications as I found them on 23 August 2024 were as Red-shouldered Hawk (lineatus Group). However, I have flagged most of these reports, so Florida eBird reviewers might have asked the relevant observers to alter their checklist(s) accordingly by the time you read this. If a reviewer contacted an observer, the observer might have:
-- made no change, perhaps causing the reviewer to invalidate the record,
-- deleted the photo(s) and retained the lineatus Group Red-shouldered Hawk entry (this happens surprisingly often!),
-- changed the entry to reflect the species ID rather than the subspecies ID and either removed the photos or left them in (this is also a common response),
-- or made the so-difficult change (can you see the dripping sarcasm?) to use the correct subspecies entry in the observer's checklist.
Seminole County -- With this bird's gray face contrasting with the warm brown rest of the head, I suggest that this is an intergrade and should be reported only to species level.
More important is this report that seems to be referable to extimus from outside that subspecies' range of regular occurrence:
This is the aforementioned "below." I once captured (with all relevant permits) an adult Red-shouldered Hawk that had been banded as a nestling in Wisconsin.
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