The effect of kleptoparasitic bald eagles and gyrfalcons on the kill rate of peregrine falcons hunting dunlins wintering in British Columbia
Kleptoparasitism in birds has been the subject of much research, and the Bald Eagle (Haliaeetus leucocephalus) is a known kleptoparasite. It has been reported to pirate ducks captured by Peregrine Falcons (Falco peregrinus), but ours is the first study to examine the effect of kleptoparasitic Bald E...
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ftunivwagenin:oai:library.wur.nl:wurpubs/445459 2024-02-04T09:59:24+01:00 The effect of kleptoparasitic bald eagles and gyrfalcons on the kill rate of peregrine falcons hunting dunlins wintering in British Columbia Dekker, T.J. Out, M. Tabak, M. Ydenberg, R.C. 2012 application/pdf https://research.wur.nl/en/publications/the-effect-of-kleptoparasitic-bald-eagles-and-gyrfalcons-on-the-k https://doi.org/10.1525/cond.2012.110110 en eng https://edepot.wur.nl/285784 https://research.wur.nl/en/publications/the-effect-of-kleptoparasitic-bald-eagles-and-gyrfalcons-on-the-k doi:10.1525/cond.2012.110110 info:eu-repo/semantics/restrictedAccess Wageningen University & Research Condor 114 (2012) 2 ISSN: 0010-5422 boundary bay central alberta ducks over-ocean flocking raptor predation info:eu-repo/semantics/article Article/Letter to editor info:eu-repo/semantics/publishedVersion 2012 ftunivwagenin https://doi.org/10.1525/cond.2012.110110 2024-01-10T23:21:15Z Kleptoparasitism in birds has been the subject of much research, and the Bald Eagle (Haliaeetus leucocephalus) is a known kleptoparasite. It has been reported to pirate ducks captured by Peregrine Falcons (Falco peregrinus), but ours is the first study to examine the effect of kleptoparasitic Bald Eagles on the kill rate of shorebird-hunting Peregrines and indirectly on a population of Dunlins (Calidris alpina) wintering in coastal British Columbia. Bald Eagles increased seasonally and yearly from October 2008 to January 2011. When eagles were scarce, Peregrines hunted ducks as well as Dunlins. Conversely, when eagles were numerous Peregrines hunted Dunlins only. In 56 instances, one or more eagles closely followed hunting Peregrines and retrieved 13 Dunlins dropped or downed by the falcons. The Peregrines were also kleptoparasitized by Gyrfalcons (Falco rusticolus), which pirated 11 Dunlins from Peregrines. Observed losses to kleptoparasites amounted to 24 (36%) of 67 Peregrines' captures. The kill rate per hour of observation was 0.05 hr-1 in October and November when eagles and Gyrfalcons were few but significantly higher at 0.18 hr-1 during January and February. In January 2011, when intraguild kleptoparasites were most abundant, the Peregrine's kill rate was 0.30 hr-1. These results support the hypothesis that kleptoparasites had an indirect effect on a population of wintering Dunlins because Peregrines compensated for prey lost to kleptoparasites by increasing their kill rate. Article in Journal/Newspaper Calidris alpina Falco peregrinus Falco rusticolus Wageningen UR (University & Research Centre): Digital Library Boundary Bay ENVELOPE(-101.934,-101.934,60.034,60.034) The Condor 114 2 290 294 |
institution |
Open Polar |
collection |
Wageningen UR (University & Research Centre): Digital Library |
op_collection_id |
ftunivwagenin |
language |
English |
topic |
boundary bay central alberta ducks over-ocean flocking raptor predation |
spellingShingle |
boundary bay central alberta ducks over-ocean flocking raptor predation Dekker, T.J. Out, M. Tabak, M. Ydenberg, R.C. The effect of kleptoparasitic bald eagles and gyrfalcons on the kill rate of peregrine falcons hunting dunlins wintering in British Columbia |
topic_facet |
boundary bay central alberta ducks over-ocean flocking raptor predation |
description |
Kleptoparasitism in birds has been the subject of much research, and the Bald Eagle (Haliaeetus leucocephalus) is a known kleptoparasite. It has been reported to pirate ducks captured by Peregrine Falcons (Falco peregrinus), but ours is the first study to examine the effect of kleptoparasitic Bald Eagles on the kill rate of shorebird-hunting Peregrines and indirectly on a population of Dunlins (Calidris alpina) wintering in coastal British Columbia. Bald Eagles increased seasonally and yearly from October 2008 to January 2011. When eagles were scarce, Peregrines hunted ducks as well as Dunlins. Conversely, when eagles were numerous Peregrines hunted Dunlins only. In 56 instances, one or more eagles closely followed hunting Peregrines and retrieved 13 Dunlins dropped or downed by the falcons. The Peregrines were also kleptoparasitized by Gyrfalcons (Falco rusticolus), which pirated 11 Dunlins from Peregrines. Observed losses to kleptoparasites amounted to 24 (36%) of 67 Peregrines' captures. The kill rate per hour of observation was 0.05 hr-1 in October and November when eagles and Gyrfalcons were few but significantly higher at 0.18 hr-1 during January and February. In January 2011, when intraguild kleptoparasites were most abundant, the Peregrine's kill rate was 0.30 hr-1. These results support the hypothesis that kleptoparasites had an indirect effect on a population of wintering Dunlins because Peregrines compensated for prey lost to kleptoparasites by increasing their kill rate. |
format |
Article in Journal/Newspaper |
author |
Dekker, T.J. Out, M. Tabak, M. Ydenberg, R.C. |
author_facet |
Dekker, T.J. Out, M. Tabak, M. Ydenberg, R.C. |
author_sort |
Dekker, T.J. |
title |
The effect of kleptoparasitic bald eagles and gyrfalcons on the kill rate of peregrine falcons hunting dunlins wintering in British Columbia |
title_short |
The effect of kleptoparasitic bald eagles and gyrfalcons on the kill rate of peregrine falcons hunting dunlins wintering in British Columbia |
title_full |
The effect of kleptoparasitic bald eagles and gyrfalcons on the kill rate of peregrine falcons hunting dunlins wintering in British Columbia |
title_fullStr |
The effect of kleptoparasitic bald eagles and gyrfalcons on the kill rate of peregrine falcons hunting dunlins wintering in British Columbia |
title_full_unstemmed |
The effect of kleptoparasitic bald eagles and gyrfalcons on the kill rate of peregrine falcons hunting dunlins wintering in British Columbia |
title_sort |
effect of kleptoparasitic bald eagles and gyrfalcons on the kill rate of peregrine falcons hunting dunlins wintering in british columbia |
publishDate |
2012 |
url |
https://research.wur.nl/en/publications/the-effect-of-kleptoparasitic-bald-eagles-and-gyrfalcons-on-the-k https://doi.org/10.1525/cond.2012.110110 |
long_lat |
ENVELOPE(-101.934,-101.934,60.034,60.034) |
geographic |
Boundary Bay |
geographic_facet |
Boundary Bay |
genre |
Calidris alpina Falco peregrinus Falco rusticolus |
genre_facet |
Calidris alpina Falco peregrinus Falco rusticolus |
op_source |
Condor 114 (2012) 2 ISSN: 0010-5422 |
op_relation |
https://edepot.wur.nl/285784 https://research.wur.nl/en/publications/the-effect-of-kleptoparasitic-bald-eagles-and-gyrfalcons-on-the-k doi:10.1525/cond.2012.110110 |
op_rights |
info:eu-repo/semantics/restrictedAccess Wageningen University & Research |
op_doi |
https://doi.org/10.1525/cond.2012.110110 |
container_title |
The Condor |
container_volume |
114 |
container_issue |
2 |
container_start_page |
290 |
op_container_end_page |
294 |
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1789964206914666496 |