Hi Rich and all,

This is a very interesting piece and definitely a helpful way to begin a 
broader conversation on this topic within the bird records community.

As explained in this article, the question of how to report species and their 
subspecies is quite complex. I've thought about this a lot and have derived a 
set of guidelines that can be applied to the problem in a more general way, 
including the related challenge of reporting other sets of nested taxa, such as 
spuhs and their constituent species.

Having read the article on Red-tailed Hawk taxa in Vermont, there are some 
issues that I think deserve extra emphasis.

At the level of species and their subspecies, in most situations there is 
exactly one identifiable subspecies that is overwhelmingly more frequent and 
abundant than any other subspecies at any given site and any given date. There 
are actually surprisingly few situations in which the second most likely 
subspecies of a given species occurs frequently enough that it poses any 
challenge to the simple equation that a report of the species equals a report 
of the default subspecies in that situation. 

For a large number of species, only one subspecies has ever been recorded in a 
given area. For instance, all Northern Flickers ever studied critically in New 
York State have been Yellow-shafted, without even one exception in all of time. 
It would be flatly incorrect and misleading to include on a Vermont eBird 
checklist something like:

23 Northern Flicker--migrating
4 Northern Flicker (Yellow-shafted)--studied carefully

Such an approach would mis-represent the number of Yellow-shafted Flickers 
observed, and the appropriate approach is to report 27 flickers as one line 
item, and it doesn't really matter which category one uses because they are 
effectively identical in Vermont in the 21st Century.

At the next level of complexity, there are many cases in which one subspecies 
occurs regularly whereas others occur as rare vagrants. Thus, it can be 
presumed that all Brant observed on Long Island are hrota unless explicitly 
suspected as something else. It is simply an error to record something like 
this on a checklist from Jamaica Bay:

1 Brant (Black)--photos
300 Brant (Atlantic)--studied carefully
2,000 Brant--estimated

Again, this grossly mis-represents the number of Atlantic Brant observed. The 
2,000 neglected Brant can be assumed to be hrota because the greatest 
conceivable number of vagrant orientalis, bernicla, etc. that could be present 
is a very small number, hovering around zero at all times, and clearly smaller 
than the error implicit in the estimate. Whether one uses "Brant" or "Brant 
(Atlantic)" is almost irrelevant because the two are quantitatively equivalent 
on Long Island, but one should never use both.*

Examples of genuine numerical uncertainty are really quite few in the 
northeastern United States. Familiar examples include Greater and Lesser Snow 
Goose (though these are quite difficult to identify and should probably be left 
alone under most circumstances for that reason alone), and Yellow and Western 
Palm Warblers. Apparently Red-tailed Hawks in Vermont represent another example 
of this sort of exceptional case, because abieticola is suspected to occur, at 
least potentially, at a high enough frequency in some seasons that it would be 
inaccurate to presume that all Red-tailed Hawks are borealis.

Shai Mitra
Bay Shore, NY

*An exception to this guideline arises when a specific individual bird is 
intermediate-looking and has to be listed as generic "Brant" (with copious 
notes and photos) because it looks neither like prevailing hrota nor vagrant 
orientalis--or when a particular swan grebe might be listed as "Aechmophorus 
sp." because it looks different from the regular vagrant "Western Grebe" but 
sounds different from the mega-rarity "Clark's Grebe".....:)
________________________________________
From: bounce-121283286-11143...@list.cornell.edu 
[bounce-121283286-11143...@list.cornell.edu] on behalf of Richard Guthrie 
[richardpguth...@gmail.com]
Sent: Tuesday, February 28, 2017 7:30 AM
To: NYSBIRDS_L; hmbi...@yahoogroups.com; midhudsonbi...@yahoogroups.com
Cc: iwor...@uvm.edu
Subject: [nysbirds-l] Red-tailed Hawk subspecies and eBird reporting them

With Ian's permission, I'm delighted to share his informative article about 
differentiating Red-tailed Hawk subspecies that may also be found in New York 
State. To read the article and see the pictures, please visit the Vermont eBird 
website at:

http://ebird.org/content/vt/news/red-tailed-hawks-recognizing-subspecies-in-vermont/

And feel free to visit Vermont and report your hawk, and songbird, duck, 
woodpecker, etc. sightings up there as well.  : )

Rich Guthrie
New Baltimore,
The Greene County,'
New York

---------- Forwarded message ----------
From: Ian Worley <iwor...@uvm.edu<mailto:iwor...@uvm.edu>>
Date: Mon, Feb 27, 2017 at 7:06 PM
Subject: [VTBIRD] Red-tailed Hawk subspecies in Vermont .... and how to submit 
them to eBird
To: vtb...@list.uvm.edu<mailto:vtb...@list.uvm.edu>


Red-tailed Hawk subspecies are catching birders' eyes in neighboring states, 
and now in Vermont.  How are they recognized and how should they be reported to 
eBird and the Vermont Bird Records Committee?  What if I'm not interested in 
the subspecies?

These questions are answered in a new article just published on the Vermont 
eBird website: 
http://ebird.org/content/vt/news/red-tailed-hawks-recognizing-subspecies-in-vermont/

If you have questions regarding eBird entries of subspecies, feel free to 
contact any of the six Vermont eBird county coordinators/reviewers:  Sue 
Elliot, Craig Provost, Spencer Hardy, Kyle Jones, Ian Worley, and Kent 
McFarland.

Good birding to all as spring migration rolls in during the next many weeks!

Ian

...............................................

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Richard Guthrie

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