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THE WILSON JOURNAL OF ORNITHOLOGY • Vol 124, No. 4. December 2012 
trapping sessions were mostly relegated to the 
afternoon. I attempted one site earlier in the day 
(the trap was in place from 1140 to 1340 hrs) 
without success; 2 days later. I caught a swift at 
this site at 1824 hr.s. I made some earlier attempts 
at trapping in 2011. where the earliest a net was in 
place was 0919 hrs, but did not catch any birds 
before 1100 hrs in either year. There may be some 
value to avoiding trapping around noon,"as the net 
may be more visible to approaching swifts at this 
time due to more direct sunlight inside the 
chimney. Three swifts were caught between 
1100 and 1300 hrs, although chimney color may 
have been a factor in these cases; 60% of tailed 
trapping attempts before 1300 hrs were at 
chimneys where the interior was constructed of 
light-colored material (gray brick or terra cotta 
clay), whereas successful sites were of dark red 
brick that would naturally obscure the net. Small 
sample size prevented any formal analysis of 
capture patterns at mid-day. 
DISCUSSION 
flic Chimney Swift trapping method I describe 
here is superior to past methods for trappino 
individual birds for several reasons; (I) it can be 
installed easily by a single researcher in under 
min without scaling the chimney; (2) it will 
work on chimneys of differing sizes and shapes; 
and (3) it minimizes disturbance to birds by 
keeping trapping periods relatively short, targeted 
to an individual, and spatially removed front the 
nest within a chimney. This method has a 
reasonable effort per bird (-125 min) for 
species-specific trapping, considering that trap- 
pmg effort can extend far beyond 2 hrs per bird 
tor some species (Hernandez et al. 2006. Benfte/- 
L opez et al. 2010. Perkins et al. 2010). Most 
swifts were caught within I hr. and I recommend 
constraining trapping sessions to I hr to maximize 
the catch to effort ratio. 
The net described can easily be placed on 
chimneys with an internal diameter of 50 -100 cm 
and smaller chimneys in some circumstances. For 
example. I caught one bird at a chimney with an 
internal diameter of -30 cm; trapping proceeded 
despue the small size because it had a clay liner 
that created a smooth internal surface, and 
snagging was less of a concern. Generally, care 
needed to be taken to keep the net away from the 
chimney s ulterior walls lest i, get caught and rip. 
Chimney height could constrain placement, but ,o 
a lesser extent than traditional trapping methods 
that require access to the chimney top. This net is 
eflective as long as researchers can gel within 5- 
6 m of the chimney top (affected hy length of net 
pole). 
The presence ol researchers nearby did not 
seem to aflecl swift behavior, as birds often 
approached and immediately entered chimneys 
during periods when I was observing from the 
rooftop, or preparing the trap for placement. 
However, there was some initial avoidance by the 
approaching swift on most trapping occasions once 
the net was in place. Typical adult behavior during 
nestling provisioning involves foraging trips rang¬ 
ing Irom 15 min to 1 hr. depending on the age of 
the young, at the end of which adults will return to, 
arid quickly enter, the chimney (Fischer 19581 
During trapping periods, a bird would often 
approach within —0.5 m of the chimney opening 
bclore veering off, circling in the area, then 
icturning to the site. This could happen several 
times before the adult actually entered the 
chimney. There was no clear pattern in avoidance 
behavior that suggested how it could be minimized 
to expedite trapping, although using fabric of a 
different color in net construction, to mimic the 
appearance ol the chimney top, was considered. 
Minimizing disturbance at nest sites to avoid 
site abandonment was a primary concern. On 
thiee occasions a bird trapped at one site was 
tracked to another chimney nearby at night (via a 
contemporaneous radiotelemetry study); although 
in one case the bird was tracked to its original 
chimney at a later date. However, these were not 
\ iewed necessarily as abandonments, as it may be 
that captured birds were actually "helpers’ to the 
breeding pairs, which is a common behavior for 
Chimney Swifts (Dexter 1969). Further. there w as 
a case where two birds were caught at the same 
site on diHerein dates with no abandonment. In a 
comparable telemetry study on Vaux's Swifts 
I [C/uietura vauxi ) nesting in natural cavities in 
regon, multiple birds were also caught at the 
same site on three occasions without abandon¬ 
ment (Bull and Beckwith 1993). This suggests 
hupping multiple Chimney Swifts at the same 
nesting chimney is a feasible option. 
This net is an efficient, safe, and relatively 
simple method of trapping individual Chimney 
^witts at their nest chimneys. Trapping large 
numbers of birds at a roost, however, would still 
x* best suited to other methods as this net is 
intended to catch birds singly. There is potential 
Ibis trapping method could be used for other swift 
