Monday, April 9, 2012

Records Committees and Exotic Birds: Interview with Phil Davis

I've been interested recently in the subject of "exotic" birds and the difficulty birders have in determining their status as wild or escapees.  I've spoken to several breeders of exotic birds about their practices and how frequently birds escape, but now I wanted to talk to someone on a records committee.

Records committees are the ones who have to make the "official" decision on whether or not an exotic bird seen in the field got there on its own or with some kind of human assistance.  I have never sat on a records committee, and I wanted to know how such a body reviews birds like Smew or Greenfinches or Bar-headed Geese - birds that could theoretically be migrants. 

It interests me because all it takes it one.  Nine hundred and ninety-nine Bar-headed Geese seen in North America could be escapees, but that last one just could have been blown astray during a high-altitude migration over Asia.  Would we know?  Does anyone care to check?

After this brief chat with Phil Davis, a long-time members of the Maryland/DC Birds Records Committee, I feel confident that the answer is Yes.  I have known a few members of records committees over the years, and I haven't met a single one who doesn't take their job very seriously.  Phil continues that tradition, and his answers reveal the inherent difficulties in dealing with these types of records, as well as the common-sense approaches the MD/DCRC uses in an attempt to find an answer.  Although it still may be impossible to completely determine the origin on a bird seen in the field, there are birders out there doing their best to figure it out.

Birdist: What is your position on the MD/DC Records Committee?  How long have you been a part of that group? 

Phil Davis: I am the Secretary of the committee. I took over this position in Sept. 1993.


Birdist: Of the records that come through the MD/DC Records Committee, how is a determination made as to which birds might be domestic escapees?  Is that consideration made for all records?

PCD: I perform a first level of filtering of reports that are "presumed" exotics. If a species is not on the AOU or ABA checklist, if the species is popular as a pet or exotic, or if it does not survive in northern climes, I generally relegate them to a lower committee priority. An example of this would include a Slaty-headed Parakeet. We have a number of such reports that we intend to review sometime, but not in the near future since we are working off our backlog in other priority areas.

PCD: When the MD/DCRC reviews a record, in addition to the question of identification, there are effectively three levels of "origin" consideration that come into play.

(1) At one end of the spectrum are birds whose origin is most certainly wild or natural; for example, a Say's Phoebe or an Allen's Humingbird. These species have known patterns of vagrancy.

(2) At the other end of the spectrum are the birds whose origin is most certainly "exotic," meaning escaped or released from human captivity. An example of this category would be a Black Swan, which is a sedentary or short-distant migrant from Australia/New Zealand, that is known to be kept in captivity in ornamental waterfowl collections.

(3) In the middle are species that fall in between those two extremes. These are species considered to be of "questionable" origin, which means that the bird could be natural/wild or it could be an escaped/released "exotic;" however, there is just no way to be sure - so, it's origin is found to be "questionable." An example in this category might be a Garganey; an ornamental European/Western Asian duck, but also a species that is a long-distant migrant that clearly reaches at least the west coast of North America.

Birdist: For records that have obvious potential to be domestic escapees (a Bar-headed Goose, for example), what is the process for determining whether the bird is a wild vagrant or an escapee?

PCD: The committee members consider a number of factors in assessing the origin of reported birds. For example, does the species fit an established pattern of vagrancy and is the timing consistent with this pattern? (e.g., Allen's hummingbirds show up in our region in the fall); is the bird banded? (and what type of band); does the bird show signs of captive treatment or wear? (clipped right hind toes on waterfowl, pinioned or clipped wings, etc.); what species (if any) is the bird associating with?, is the behavior suspect? (e.g., unwary of humans), is the habitat reasonable for this species?, etc.

PCD: From a committee process standpoint, sighting reports are circulated among the nine voting members of the committee until a decision is reached or for a maximum of four rounds of review. If all of the members vote to "Accept" a record as natural/wild, the voting is over. If all nine members vote to accept as either "exotic" or "questionable" origin, then the voting is over. However, if the members are split between "accept,"  "exotic," and/or "questionable," then the report is circulated one more time so the members can review each others comments, and then the majority category prevails. 

Birdist: As part of that determination, are area wildfowl breeders or other keepers of exotic birds contacted to see if they're missing that species?  

PCD: The problem is that there is no central clearing house for wildfowl breeders, or breeders or collectors of exotics, so that a canvass has never been very effective and typically has not revealed any information of use. However, I will sometimes still try to conduct a canvass before a report is placed into circulation. For our recent report of a European Greenfinch, I tried to contact as many pet stores and exotic bird breeders as I could to see if I could learn anything relevant, but basically I received no responses. There is an information clearinghouse for species kept in zoos and I do consult this for some vagrant species, such as the Southern Lapwing that was observed near Ocean City a few years ago. 

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