About Eurasian Collared Doves . . .

[Mark Stackhouse <westwings at sisna dot com>]

With the recent sighting of Eurasian Collared Doves (ECDO) at River Lane
in Utah County, along with other recent sightings, and the apparent push
to establish a "state-first" record for this species, I thought I would
share my opinion on the "countability" of this species in Utah. Several
people have asked me what I thought about this, and whether I was
interested in "chasing" any of these sightings.

The situation with ECDO is quite a bit different than with any of the
recent "state-first" records in Utah. ECDO is an introduced species (or,
at best, a species "naturalized" from an introduced population), which
is well-established in the southeast U.S., and is spreading rapidly. By
ABA listing rules, the species is countable in a number of eastern and
southeastern states. There appears to be a strong probability that it
will eventually become established in at least parts of Utah. As far as
I know, currently the closest "wild" populations of ECDO to Utah are in
SE Arizona and New Mexico. Does anyone know of others?

According to ABA listing rules, introduced species can be "counted" once
they're established as a self-sustaining population. Presumably, vagrant
individuals from an established population would be treated just as a
native species, and be countable as well. So why would there be any
problem with counting ECDO in Utah, when the birds seen could easily be
from the expanding wild population?  As we have just seen with the River
Lane birds, the problem lies with the fact that ECDO is a commonly kept
(and, sometimes, not-so-well-kept) cage bird in Utah. These captive
birds frequently escape or are released. There is simply no way to tell
with any degree of certainty whether any individual is an escapee, and
not countable, or a vagrant "wild" bird, and thus countable. In my
opinion, all of the recent sightings are much more likely to be from
escapees. Considering the pattern of spread of this species so far, I
would expect the first wild birds to appear in southern Utah, not the
along Wasatch Front. Given such a high degree of doubt regarding the
origin of these birds, none of these sightings should be counted.

So, when will we have our "state-first" ECDO? As I said before, the
situation with ECDO is quite different from that with native species. I
don't believe that we will ever be able to point to a particular
sighting as our "state-first" record for ECDO. Even once they are
established, the local population of ECDO is likely to be continually
augmented be escaped captive birds, creating some doubt as to the origin
of any individual bird. However, at some point, the population of ECDO
in Utah will be so well established that the chances of any individual
being an escapee will be much smaller than the chances of it being a
wild bird. At that point, ECDO will at least be locally common, if not
common statewide, and essentially all sightings of ECDO will be
countable. It is much the same situation as with Ring-necked Pheasant,
which is well-established, but has it's population augmented continually
by escapees and releases from game-farms and other captive sources. We
consider most pheasant sightings countable, even though there is a
chance that the bird seen was once a captive.

When (if ever) will the population of ECDO in Utah be so well
established that it is a "countable" bird? Of course, no one knows the
answer to this question. However, since the ABA defers to individual
state records committees to determine the status of birds within any
given state, the ECDO will appear on the Utah list by a ruling of the
Utah Bird Records Committee. Thus, our "state-first" ECDO will not come
in a dramatic sighting of a lost individual, like the Magnificent
Frigatebird, Field Sparrow, or Elf Owl, but rather by a vote of the
committee.

Until then, I'll pass on the chasing . . .

Good birding!

Mark

Mark Stackhouse
Westwings, Inc.
1432 Downington Ave.
Salt Lake City, UT 84105
(801) 487-9453
westwings@sisna.com


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