RESEARCH

PEREGRINE FALCON

PUBLICATIONS


Abstracts for scientific meetings are posted below for presentations given relating to MRF's research on Peregrine Falcons.  Additional publications will be listed here as they are published.

Raptor Research Foundation - October 2005 - Green Bay, Wisconsin
Genetic origin of Peregrine Falcons (Falco peregrinus) breeding in eastern Canada
Presented by David Bird; co-authors Marcel Gahbauer and David Bird
Project partners:  Avian Science and Conservation Centre, Ontario Ministry of Natural Resources 
ABSTRACT: 
Between 1975 and 1996, over 1500 captive bred Peregrine Falcons were introduced by hacking into nest sites in southern Canada.  All the captive breeders originated from wild nests south of the treeline, considered to be within the range of the anatum subspecies.  Some of the released falcons returned to breed in southern Canada, while others bred in the eastern US.  Conversely, many of the peregrine falcons breeding in Canada originated from releases and wild sites in the US, where several subspecies were used in captive breeding programs.  This is most evident in southern Ontario, where Peregrine Falcons resumed breeding in 1995 after an absence of over thirty years.  From 1995 through 2004, 30 breeding adults were observed, of which nine were of Canadian origin, 12 of American origin, and nine were unbanded birds of unknown origin.  However, of the Canadian birds, four had at least one parent originating from the US breeding program.  This paper reviews our knowledge of the origin of Peregrine Falcons that breed in Ontario and elsewhere in Canada, based on band recoveries.

Raptor Research Foundation - November 2004 - Bakersfield, California
Nest site characteristics and productivity of urban Peregrine Falcons (Falco peregrinus) in southern Ontario
Presented by Marcel Gahbauer; co-author David Bird
Project partner: Ontario Ministry of Natural Resources
ABSTRACT: 
In 1995, two Peregrine Falcon pairs nested in southern Ontario, marking the first successful breeding in the region in over thirty years.  Since then, 18 sites have been used, including a one-year high of 10 active nests in 2004.  From 1995 to 2004, 217 eggs were documented at 63 nesting attempts. The overall hatching rate was 65.9%, with higher success at southwest, south, or southeast facing nests (76.8%, n=28) than at others (56.8%, n=35). Two-thirds of nesting attempts were at sites with full overhead cover; hatching success at these averaged 76.6% versus 44.4% at sites with partial or zero cover.  Of all chicks hatched (n=143), 95.8% survived to fledging, and 78.3% survived to independence.  To supplement natural productivity, 49 juveniles were hack released at 15 sites between 1999 and 2004.  Government biologists and/or experienced volunteers monitored all nests and releases. Fledglings were rescued whenever injured, or at risk of injury from ground predators and/or traffic.  Only 8.2% of hack released peregrines were rescued, compared to 41.6% of wild hatched juveniles.  Of young hatched between 1995 and 2003, the fate, one year post-fledging, is known for 43.7% (n=119) of wild hatched and 42.2% (n=45) of hack released birds.  First year mortality was 63.5% for wild hatched individuals and 68.4% for hack released birds.  Of the survivors, 15 wild hatched individuals have produced 101 offspring, while the only breeding hack released bird has produced five. Two of the breeders displaced one of their parents from their natal sites, two took over existing Ontario territories, five established new territories in southern Ontario, and the remaining seven nested in Michigan, Ohio, or New York.  These results from Ontario suggest that a broader review of the eastern Peregrine Falcon population could reveal important patterns to better guide future management efforts.

Hawk Migration Association of North America - March 2003 - Corpus Christi, Texas
Patterns in the migratory movements of North American Peregrine Falcons
Presented by Marcel Gahbauer; co-authors David Bird, Geoffrey Holroyd
Project partners:  McGill University, Canadian Peregrine Foundation, Canadian Wildlife Service
ABSTRACT:  Satellite telemetry has previously been used to document the movements of Peregrine Falcons (Falco peregrinus) from breeding grounds in western North America, winter territories in Mexico, and migratory stopovers along the Atlantic Coast.  This study is the first to focus primarily on the movements of urban Peregrine Falcons, and to be targeted mostly at juveniles.  Between 1997 and 2002, 27 Peregrine Falcons from Alberta, Ontario, Quebec, New York, and Pennsylvania were fitted with satellite transmitters during the summer months.  Nine individuals died or were otherwise lost from communication before the end of summer.  Among the others, nine undertook long-distance migrations of 2000 km or more, six migrated shorter distances, two moved to locations within 100 km of their origins, and one did not disperse at all.  Time of dispersal, in number of days post-fledging, was longer for urban juveniles than for those from rural sites.  Similarly, captive-bred juveniles dispersed more slowly than those raised in the wild.  Among urban peregrines, captive-bred individuals showed a much greater migratory tendency.  Regardless of origin, almost all moved to a coastal location for the winter.  Migratory paths were varied, but many individuals frequented Florida and the east coast of Mexico.  For six birds, both fall and spring migrations were recorded; all returned to within 50 km of their points of origin.  Those which wintered in North America or Mexico returned by similar routes, while those which migrated further south crossed long distances of open water in the fall, but followed terrestrial routes in the spring.

Argos Animal Tracking Symposium - March 2003 - Annapolis, Maryland
Peregrine Falcons:  insights gained throughs satellite telemetry
Presented by Marcel Gahbauer; co-authors David Bird and Geoffrey Holroyd
Project partners:  McGill University, Canadian Peregrine Foundation, Canadian Wildlife Service
ABSTRACT: 
Previous researchers have used satellite telemetry to document the migration of Peregrine Falcons (Falco peregrinus) between northern breeding territories and wintering grounds in Central and South America.  The present study is focused primarily on the dispersal and migration of juvenile Peregrine Falcons from urban environments.  Seventeen such individuals have been tracked since 1998, in addition to five juveniles from rural sites and five adults.  Birds were fitted with a PTT at or near their nest sites in Alberta (n = 6), Ontario (n = 14), Quebec (n = 2), New York (n = 1), and Pennsylvania (n = 4).  Nine individuals died or were otherwise lost from communication within three months, and an additional three falcons died later while still wearing the PTT.  In several cases, the site of death could be located using the telemetry data, allowing the cause of mortality to be determined; factors identified include vehicle collisions, predation, and electrocution.  Of the 18 individuals tracked for three months or longer, nine undertook long-distance migrations of 2000 km or more, six migrated shorter distances, two moved to locations within 100 km of their origins, and one did not disperse at all.  Among the migrants, some departed directly from their original territory, while others first dispersed locally before undertaking longer journeys.  Time of post-fledging dispersal was later for urban juveniles than for those from rural sites.  Satellite telemetry has proven to be effective at describing both the spatial and temporal patterns of Peregrine Falcon movements.

 

2002- The Migration Research Foundation Inc.