Écologie de la reproduction du faucon pèlerin au Nunavut

Abstract

Découvrir la revue Citer cet article Jaffré, M., Franke, A., Anctil, A., Galipeau, P., Hedlin, E., Lamarre, V., L'Hérault, V., Nikolaiczuk, L., Peck, K., Robinson, B. & Bêty, J. (2015). Écologie de la reproduction du faucon pèlerin au Nunavut. Le Naturaliste canadien, 139(1), 54-64. doi:10.7202/1027671ar Résumé de l'article Le déclin historique du faucon pèlerin (Falco peregrinus) observé en Amérique du Nord au milieu du xxe siècle a été principalement attribué à l'échec de reproduction causé par les polluants organochlorés persistants. C'est dans ce contexte que le Arctic Raptor Project a été initié, en 1982, dans le but d'étudier la reproduction de faucons pèlerins F.p. tundrius nichant dans l'Arctique. Nous présentons ici une synthèse des principaux travaux conduits dans le cadre de ce programme de recherche réalisé essentiellement dans la région de Rankin Inlet, mais aussi plus récemment près d'Igloolik et sur l'île de Baffin au Nunavut. Des résultats portant sur le régime alimentaire, la phénologie de la reproduction, la croissance et la survie des jeunes, ainsi que sur la dynamique de population sont présentés. Le suivi à long terme dans la région de Rankin Inlet a permis de mettre en lumière, entre autres, une baisse du nombre de jeunes au cours des 3 dernières décennies. Des épisodes de fortes précipitations estivales, plus fréquents dans l'aire d'étude ces dernières années, semblent en partie responsables de ces diminutions. En outre, l'étude des rapaces nichant dans l'Arctique est cruciale pour comprendre les conséquences sur la dynamique des populations, notamment des changements climatiques, de l'environnement (p. ex. diminution des polluants organochlorés) et de la structure et du fonctionnement de l'écosystème arctique. AbstractThe historical decline of the peregrine falcon (Falco peregrinus) in North America during the 20t h century was mainly attributed to reproductive failure due to the accumulation of persistent organochloride pollutants. As a direct result to this finding, the Arctic Raptor Project was established in 1982, and its goal was to monitor the breeding success of Arcticnesting peregrine falcons (F.p. tundrius). The present article provides a synopsis of the major findings of its research, which was principally conducted around Rankin Inlet (Nunavut), but also, more recently, around Igloolik and on Baffin Island (Nunavut). The results cover raptor feeding regimes, reproductive phenology, growth and survival of young, and population dynamics. The long-term Rankin Inlet study has identified, among other things, a decrease in the number of young fledged over the past 3 decades. Episodes of heavy summer rain, which have occurred more frequently in recent years, appear, in part, to be responsible for this decline in reproductive output. The continued study of Arctic-nesting raptors is crucial to our understanding of population dynamics, including how these are affected by changes in climate and in the environment (e.g., reductions in organochloride pollutant levels), and on the stru...

Weather‐mediated decline in prey delivery rates causes food‐limitation in a top avian predator

“…The reduction in the number of eggs laid per occupied site that was observed in 2012 was almost certainly the result of the severe rain event (13–18 June) that occurred during the laying period (mean lay date for this population is 15 June ± 3.6 days) (Jaffré et al ). Precipitation during the laying period can reduce the probability of laying and clutch size in a variety of raptor species (Mearns and Newton , Olsen and Olsen ).…”

“…In 2010 and 2011, mean temperatures in June, July and August were higher than the long‐term mean (4, 11 and 9°C) and total rainfall was lower (22–35 mm). In 2012 a severe spring rain event in mid‐June (80 mm over seven days) coincided with the peak laying period for peregrine falcons (15 June ± 3.6 days) (Jaffré et al ). Although temperatures in 2012 was similar to the long‐term mean (2, 8 and 7°C), there were a greater number of wet weather days (fog, and/or rain, and/or drizzle, and or snow) during the critical brood rearing period (from hatching to two weeks of age).…”

“…Although temperatures in 2012 was similar to the long‐term mean (2, 8 and 7°C), there were a greater number of wet weather days (fog, and/or rain, and/or drizzle, and or snow) during the critical brood rearing period (from hatching to two weeks of age). During the critical nestling rearing period (a 20 day period from 16 July–6 August based on mean hatch date July 15 ± 3.6 days; (Jaffré et al )) in 2010, there were five days with periods of wet weather, six days in 2011 and 10 days in 2012 (Environment and Climate Change Canada date from the Igloolik Airport; < http://www.weather.gc.ca >). Thus approximately one in four days during the critical nestling rearing period were wet weather days in 2010 and 2011 compared to one in two days in 2012.…”

“…Nestling growth rates were similar in 2010 and 2011, but were markedly different in 2012; for both sexes the period of rapid growth was of shorter duration in 2012 and asymptotic weights were lower. The reduction in the number of eggs laid per occupied site that was observed in 2012 was almost certainly the result of the severe rain event (13-18 June) that occurred during the laying period (mean lay date for this population is 15 June  3.6 days) (Jaffré et al 2015). Precipitation during the laying period can reduce the probability of laying and clutch size in a variety of raptor species (Mearns andNewton 1988, Olsen andOlsen 1989).…”

“…The Arctic peregrine falcon Falco peregrinus tundrius is a generalist top predator with a diverse diet that includes songbirds (Passeriformes), shorebirds (Scolopacidae and Charadriidae), ducks (Anatidae), gulls (Laridae, Sternidae and Stercorariidae), black guillemots Cepphus grille (Alcidae), and, when available, collared lemmings Lemmus trimucronatus, brown lemmings Dicrostonyx groenlandicus, and Arctic ground squirrels Urocitellus parryii. (Steenhof andKochert 1988, Kattsov et al 2005), Arctic peregrine falcons rely on insectivorous birds as their primary prey (Reid et al 1997, Jaffré et al 2015, particularly the flux of juveniles that become available when peregrine nestlings are growing and demand for food is high (Court et al 1988, Rosenfield et al 1995. In addition, lemmings, which are known to cycle in Arctic ecosystems (Predavec et al 2001, Krebs et al 2011, are also an important prey species for Arctic peregrine falcons raising young (Bradley and Oliphant 1991).…”