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by
Michael G. Shepard and Paul G. Levesque
May 2005
Introduction
In 2004 we initiated a project to gather and synthesize information
on Black Swift distribution in British Columbia. Data were
gathered in an ad hoc fashion. Many observers submitted database
forms for incidental observations and in some cases we gleaned
information from the various birding newsgroups around the province.
Potential nest sites were also visited in an attempt to document
breeding data.
Results
A total of 153 sighting records were gathered, contributed by 60+
observers. Figure 1 graphs the seasonal tallies. The first birds were reported April
17, with the last seen September 20. The majority of birds were
seen in late May/early June and during the first two weeks of July.
Very few were reported at other times, despite moderate effort to find
them. Fall migration likely began in early August when small
numbers appeared in numerous scattered locations.
A general breakdown of observation numbers is a
follows: Lower Mainland - 68, Vancouver Island - 50, Interior -
16. The most northerly detections came from the Prince George/Vanderhoof
area, peaking with a showing of 600 birds at Nulki Lake on May 29 (Jack
Bowling, Cathy Antoniazzi, Nancy Krueger). Other large
concentrations included up to 400 individuals over Grant Narrows, Pitt
Meadows in late May and early June (Rick Toochin et al.) and 200 in
Parksville-Qualicum July 6 (Guy Monty). The largest number
reported during the fall migration was the 30 tallied by Kris Andrews at
Williams Lake on August 27. Over 35% of mainland observations were
contributed by Gord Gadsden who survey the Chilliwack/Hope area.
He found only small numbers, but over a wide area.
Only one active nest was found - at Brandywine
Falls on the Brandywine
River. It was located on July 26 when an adult was discovered on
the nest. A single fully grown chick was there until at least
August 21.
.
Figure 1. Seasonal observations of
Black Swift in British Columbia during 2004.
Discussion
The Black Swift presents a vexing
conservation problem. We know virtually nothing about any aspects
of their life history in British Columbia. Major questions to
investigate include:
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With up to 80% of the North
American population of Black Swifts thought to breed in western
Canada, there are only eight confirmed nesting sites. Where are the
others?
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The majority of Black Swifts
likely fledge between mid-August and early September. However,
by mid-August, the species is not often reported. When does
the bulk of the population depart?
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Individual Black Swifts have been
documented as living at least 15 years (Lowther
and Collins 2002). Perhaps a large number of the birds
encountered in the province may be non-breeders Could the
total breeding population in BC be fewer than 1000 pairs?
Due to the ad hoc nature of the data
collection, there is currently little potential for trend
analysis. However, two locations were identified as reliable
foraging sites: Grant Narrows at Pitt Meadows and Woss on northern
Vancouver Island. Relatively consistent numbers were reported
there in June and July. These sites have potential to be developed
as long term population monitoring stations.
The Black Swift has no special
conservation designation anywhere in Canada. It is important to
know where theses birds are and what threats there may be to the
species' survival. It is hoped that this project will take us a
little closer to understanding the species.
Plans for 2005
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Continue data gathering of incidental
observations (2004 onwards, plus selected historical records) to
further document suspected seasonal distributional and apparent
abundance patterns. Main focus is on British Columbia. However
incidental observations from elsewhere in North America are
welcome.
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Conduct more intensive nest site searches in
British Columbia.
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Further document nesting habitat and breeding
chronology in British Columbia.
If you are interested in helping out, please visit
our Black Swift Survey Page
for more information on the project.
Observers (note that not all observers were
listed on the newsgroups - please let us know if we missed you):
Kris Andrews, Cathy Antoniazzi, Jack Bowling, Quentin Brown, Peter
Candido, Glen Carlson, Brian Carson, Paul Chytyk, Dianne Cooper, Douglas
Cooper, Marcia Danielson, Grant Danielson, Peter Davidson, Wayne Diakow,
Adrian Dorst, Jamie Fenneman, Gord Gadsden, Kristen Gadsden, Kris
Gardner, Jeremy Gatten, Adrian Grant-Duff, Eleni Havalias, Carmen
Holschuh, John Ireland, Len Jellicoe, Nancy Krueger, Adrian Leather,
Paul Levesque, Rob Lyske, Derrick Marven, Carolyn McGhee, Jack McGhee,
Mitch Meredith, Lynn Miller, Mike Miller, Guy Monty, Danielle Nicholson,
Dean Nicholson, Jeff O'Kelly, Stan Olson, Istvan Orosi, Ivar Petersen,
Phil Ranson, Anne Redfearn, Nancy Ricker, Ian Routley, Chris Saunders,
Laurie Savard, Gerry Shaw, Verena Shaw, Cynthia Shepard, Michael
Shepard, John Toochin, Rick Toochin, Danny Tyson, Guy Wapple, Tony
Wideski, Mark Wynja, Alan Young, Kathy Young.
Project Links:
Literature Cited
Lowther, P.E., and C.T.
Collins. 2002. Black Swift (Cyseloides niger). In The
Birds of North America, No. 676 (A. Poole and F. Gill, eds.). The Birds
of North America, Inc., Philadelphia, PA.
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