Texbirders,
a few things need to be straightened out regarding this continuing thread.
First, referring to Justin’s assumption that "BLOT was written well before
Vaux’s Swifts were confirmed wintering along the northern Gulf of Mexico" and
his effort to minimize the importance and reliability of information and data
from Oberholser’s A Bird Life of Texas (BLOT), it must be said that a quick
first hand look into the tome 1, page 476 would have made him realize that he
is absolutely mistaken. Not only does Oberholser write a whole chapter about
the Vaux’s Swift, he includes the information that the species rarely winters
north to s. Louisiana and adds sighting dates that lead him to declare it
“hypothetical” for Texas. Therefore we can safely assume that Oberholser was
well aware of the presence of Vaux’s Swift along the northern Gulf of Mexico
during the winter months and any extreme early date he gave for Chimney Swift
would have taken that into consideration.
Also, I continue to be perplexed by the “shock” Justin proclaims that an ebird
reviewer would have accepted a Chimney Swift report with scant details from 9
March. I am reminded of that saying “if you hear hoofbeats (in this case, see a
swift on 9 March on the Texas coast) think horse (Chimney) not Zebra (Vaux’s).
We have read a first hand report from Paul Kyle, Project Director of the
Chimney Swift Conservation Association, who draws on decades of first hand
observations and reliable reports from his vast network of associates which
have reported Chimney Swifts as early as 1 March. Add to that the recent very
interesting and timely observation and report from Bob Becker who saw thousands
of Chimney Swift on 7 March streaming north just offshore from Belize City.
Highly unlikely that there wouldn’t have been some smaller numbers ahead of
this big push. And then there is the Handbook of Texas Birds by Lockwood and
Freeman, which Justin considers a somewhat more reliable source than BLOT, and
which gives the migration window as starting in early March. The fact that this
publication does not give individual sighting dates that the authors based
their migration time frame on is purely one of space constraints but believe
me, a lot of reliable, published, pre e-bird sources were laboriously sifted
through to arrive at those dates.
If Justin chooses to disregard all that and remain of the opinion that a
Vaux’s Swift on 9 March would be just as or even more likely than a Chimney
Swift it is, of course, his prerogative but I hope Texbirders will keep the
above preponderance of data in mind and not jump to the conclusion that a 9
March swift is likely a Vaux’s.
Disregarding/calling into question records that pre-date ebird and the advent
of digital photography feels a bit like re-inventing the wheel to me.
Petra Hockey
Port O’Connor, TX
Subject: Re: Possible Vaux’s Swift at Armand Bayou (Harris Co.)
Date: Sat Mar 16 2019 12:28 pm
From: justin.bosler AT gmail.com
Petra, Texbirds,
The TOS Handbook of Texas Birds mentions early March, though no specific
date(s) is/are provided. However, unless the 19 Feb record was photographed,
sound recorded or collected as a specimen it probably cannot be verified as a
Chimney Swift, instead it was likely assumed to be one. If I'm not mistaken,
BLOT was written well before Vaux's Swifts were confirmed wintering along the
northern Gulf of Mexico.
Subject: Re: Possible Vaux's Swift at Armand Bayou (Harris Co.)
Date: Sat Mar 16 2019 12:57 pm
From: justin.bosler AT gmail.com
Matt,
You've done a better job of getting across my point. Why not Chaetura
species? The eBird reviewer accepted the record as Chimney Swift with scant
details provided. That's what I found shocking. I posited Vaux's because that
is the only other Chaetura species that's been documented with both specimen
and photographs in the northern Gulf of Mexico. And, they are occurring with
more frequency in the winter to our east.
Also, it's just as much advent of widely-accessible digital photography and
sound recording as it is eBird when it comes to better record-keeping.
Voucher specimens and hearsay are all we have to go off of when it comes to
historical records. Personally, that's why I put less faith in BLOT than more
modern resources such as the TOS Handbook.
Best regards,Justin BoslerAustin, Texas
