English and Scientific
names: |
Vaux’s Swift (Chaetura vauxi vauxi?) |
Number of individuals: |
8 |
Locality: LOUISIANA: |
E. Baton Rouge
Parish |
Specific Locality: |
over City Park
Lake on Morning Glory Ave./May St., Baton Rouge |
Date(s) when observed: |
24 January 2008 |
Time(s) of day when
observed: |
~4:15 PM CST |
Reporting observer and
address: |
Devin Bosler Baton Rouge, LA |
Other observers accompanying reporter who also
identified the bird(s): |
Van Remsen, David Anderson |
Other observers accompanying reporter who independently
identified the bird(s): |
none |
Light conditions (position of bird in relation to
shade and to direction and amount of light): |
Overcast w/ low
ceiling and adequate afternoon light. |
Optical equipment: |
Zeiss Victory FL 8x42 (excellent condition) |
Distance to bird(s): |
ca. 50 meters up at closest point |
Duration of observation: |
~10 min. |
Habitat: |
Suburban shallow,
freshwater lakes surrounded by residential/disturbed deciduous woodlots
(primarily live oaks). |
Behavior of bird: |
The swifts were
screening insects in a compact group over the lake in association w/ Purple
Martins and Tree Swallows. Rapid
wing beats followed by brief glides was noted as they flew in and out of
view. |
Description:
|
The group of
Vaux’s Swifts (VASW) were screening aerial insects over the lake w/ Purple
Martins (PUMA) and Tree Swallows (TRSW). First, a single Chaetura
swift came into view followed by 5 more (the other 2 were spotted later). A relatively small swift w/ a
noticeably pale gray-brown throat and breast contrasting w/ the belly and
upperparts. Tails were very
short and inconspicuous in flight.
The flight style was diagnostic w/ very rapid, shallow wing beats
followed by a short period of gliding.
The vocalizations were the ID clincher. Calls were a series a high-pitched chip notes and
twittering which blended together into an ‘insect-like’ trill. |
Voice: |
A rapid series of
high-pitched twittering and chipping notes. Heard faintly over traffic noise. |
Similar species: |
Most reliably, Chimney
Swift (CHSW) can be eliminated by voice. CHSW has a lower-pitched chipping and twittering. CHSW exhibits a slightly different flight
style (less rapid wing beats and longer glides on relatively long wings) and
has a longer, more conspicuous tail in flight. Also CHSW is more uniform dark below, lacking a noticeably
pale throat and breast. CHSW can
be further eliminated by the date of observation. There are no previous accepted records of CHSW from
January. |
Photographs or tape recordings obtained? |
Unfortunately, no. |
Previous experience with this species: |
Familiar with VASW
from CA and several previous encounters in Baton Rouge, LA. |
Identification aids: |
at time of observation: after observation: National Geographic Complete Birds of N.A. (Alderfer
et al. 2005) and Sibley's Guide to Birds (Sibley 2003).none |
This description is
written from: |
__Yes___ notes made during the observation __Yes___notes made after the observation __Yes___memory. |
Are you positive of your identification? If not,
explain: |
Yes, very
confident. |
Reporter: |
Devin
Bosler
|
Date and time: |
31 January 2008 3:00 PM CST |