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Colonial nesting is associated with numerous costs and benefits that may either increase or decrease fitness of individuals in colonies. Fitness can vary as a function of the location within colonies and individuals may attempt to improve their fitness by changing their nesting location between years. We used a 24 year data set on nest locations within the Tutakoke River Black Brant (Branta bernicla nigricans) colony on the Yukon-Kuskokwim Delta in western Alaska and multi-state capture-mark-recapture models to study the movement of individuals between 2 spatial strata in the colony separated by the Tutakoke River. We found that individuals nesting in a stratum that experienced higher levels of predation by arctic foxes (Vulpes lagopus) were 3 times more likely to move to the other stratum than vice versa, despite slightly higher risk of tidal flooding in the second stratum. These results suggest that Black Brant changed nest locations in an attempt to maximize reproductive fitness and they are consistent with a long-term shift in nest density over the course of the study. Received 28 May 2021. 10 February 2022. Key words: arctic, coloniality, dispersal, geese, multi-state, nesting, private information, public information. La anidacion en colonias esta asociada con numerosos costos y beneficios que pueden aumentar o reducir la sobrevivencia de individuos en colonias. La sobrevivencia puede variar en funcidn de la localizacion del nido al interior de la colonia y los individuos pueden intentar mejoras en su sobrevivencia mediante el cambio de sitio de anidacion en diferentes afios. Usamos un juego de datos de localizacion de nidos de 24 arios en la colonia de gansos Branta bernicla nigricans del rio Tutakoke en el delta del Yukon-Kuskokwin en el occidente de Alaska y modelos multiestado de capura-marcado-recaptura para estudiar el movimiento de individuos entre 2 estratos espaciales en la colonia separados por el rio Tutakoke. Encontramos que los individuos anidando en un estrato que experimento mayores niveles de depredacion por zorros del Artico (Vulpes lagopus) tenian una probabilidad 3 veces mayor de moverse al otro estrato que viceversa, atin pese a un ligeramente mayor riesgo de inundacion por mareas en el segundo estrato. Estos resultados sugieren que estos gansos cambiaron la ubicacion de sus nidos para intentar maximizar su sobrevivencia reproductiva y son consistentes con un cambio a largo plazo en la densidad de nidos a largo plazo a lo largo del periodo de este estudio. Patabras clave: artico, colonialidad, dispersion, ganso, informacion privada, infonnacion publica, multi-estado., Colonial breeding is a common trait across a wide variety of taxa, including mammals, reptiles, insects, and birds, despite numerous negative consequences of living in high densities of conspecifics. These [...]

Reported peak years of lemming (Lemmus spp. and Dicrostonyx spp.) and Arctic fox (Vulpes lagopus (Linnaeus, 1758)) abundance were compiled from the literature for 12 locations spanning 127 years. The mean period of the 34 reported lemming and Arctic fox cycles from 1868 to 1994 was 3.8 years, suggesting that the period of the 4-year cycle is actually 3.8 years. Peak population years were predicted using a simple model based on a 3.8-year lunar cycle. For nearly 130 years, reported years of peak abundance of lemmings and Arctic foxes were significantly correlated with and have persistently stayed in phase with predicted peak years ofabundance. Over the same period, predicted peak years oflemming abundance have been closely aligned with peak (i.e., La Nina) years of the January--March Southern Oscillation Index (SOI). From 1952 to 1995, peak flowering in Norway tended to occur close to trough June--August SOI (El Nino) years. The hypothesis proposed is that the 3.8-year lunar cycle governs the timing of the lemming cycle, but it does not cause the population cycling itself. If this hypothesis is true, then the heretofore unexplained source of the persistent periodicity and quasi-metronomic regularity of the lemming cycle is identified. Key words: 4-year population cycle, lemming, Lemmus spp., Dicrostonyx spp., Arctic fox, Vulpes lagopus, zeitgeber, population dynamics, lunar cycles, ENSO, Southern Oscillation Index, SOI. Les années rapportées de pointe d'abondance des lemmings (Lemmus spp. et Dicrostonyx spp.) et des renards arctiques (Vulpes lagopus (Linnaeus, 1758)) ont été compilées à partir d'études publiées pour 12 endroits et couvrant 127 années. La période moyenne des 34 cycles d'abondance rapportés des lemmings et des renards arctiques de 1868 à 1994 est de 3,8 années, ce qui sous-entend que la période du cycle de 4 ans est en fait de 3,8 années. Les années de pointe des populations ont été prédites à l'aide d'un modèle simple basé sur un cycle lunaire de 3,8 années. Pour près de 130 ans, les années rapportées de pointe d'abondance des lemmings et des renards arctiques étaient significativement corrélées aux années prédites de pointe d'abondance et demeuraient en phase avec ces dernières. Au cours de la même période, les années prédites de pointe d'abondance des lemmings coïncidaient aussi étroitement avec les années de pointe (c.-à-d. La Niña) de l'indice d'oscillation australe (IOA) pour les mois de janvier à mars. De 1952 à 1995, les pointes de floraison en Norvège avaient tendance à se produire aux alentours d'années de creux de l'IOA pour les mois de juin à août (El Niño). L'hypothèse est proposée que le cycle lunaire de 3,8 années régit le moment du cycle des lemmings, mais qu'il n'est pas la cause des cycles démographiques comme tels. Si cette hypothèse s'avère, la source jusqu'ici non expliquée de la périodicité persistante et de la régularité quasi métronomique du cycle des lemmings est maintenant établie. [Traduit par la Rédaction] Mots-clés: cycle démographique de 4 ans, lemming, Lemmus spp., Dicrostonyx spp., renard arctique, Vulpes lagopus, zeitgeber, dynamique des populations, cycles lunaires, ENSO, indice d'oscillation australe, IOA., Introduction The persistent 4-year population cycle of lemmings (Lemmus spp. and Dicrostonyx spp.), voles (Microtus spp. and Clethrionomys spp.), and their predators, including the Arctic fox (Vulpes lagopus (Linnaeus, 1758)) [...]

ABSTRACT. Female common eiders (Somateria mollissima v-nigrum) generally select nest sites in areas with driftwood cover. Previous studies of common eiders have shown a positive relationship between nest success and [...]

(Received 27 October 1999; accepted in revised form 7 March 2000) ABSTRACT. Arctic foxes (Alopex lagopus) are the main predators of many arctic-nesting birds, and such predation can have a [...]

(Received 7 July 1998; accepted in revised form 9 June 1999) ABSTRACT. We investigated the diet of arctic foxes (Alopex lagopus) in the Karupelv valley, East Greenland, during the summer [...]

CHRISTIAN M. O. KAPEL(1) (Received 14 October 1997; accepted in revised from 11 March 1999) ABSTRACT. The gastrointestinal tracts of 254 arctic foxes (Alopex lagopus) trapped or shot in Greenland, [...]

OLAV STRAND,(1),(2) JOHN D.C. LINNELL,(1) STEINAR KROGSTAD(1) and ARILD LANDA(1) (Received 8 September 1997; accepted in revised form 29 January 1999) ABSTRACT. Between 1988 and 1995, dens in three adjacent [...]

(Received 23 April 1997; accepted in revised form 15 December 1997) 1 Department of Biology, University of Saskatchewan, 112 Science Place, Saskatoon, Saskatchewan S7N 5E2, Canada; Jason.Bantle@ec.gc.ca 2 Prairie and [...]

1 Alaska Science Center, Biological Resources Division, U.S. Geological Survey, 1011 East Tudor Road, Anchorage, Alaska 99503, U.S.A.; mike_anthony@nbs.gov (Received 3 January 1996; accepted in revised form 25 February 1997) [...]