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James S Sedinger - One of the best experts on this subject based on the ideXlab platform.

  • Dynamics of Dispersed-Nesting Black Brant on the Yukon-Kuskokwim Delta
    Journal of Fish and Wildlife Management, 2020
    Co-Authors: James S Sedinger, Thomas V Riecke, Phillip A. Street, Julian B. Fischer
    Abstract:

    The number of black brant Branta Bernicla nigricans nests within major breeding colonies on the Yukon-Kuskowkim Delta has declined since 1992. It has been hypothesized that these declines are parti...

  • incubation capacity contributes to constraints on maximal clutch size in brent geese Branta Bernicla nigricans
    Ibis, 2017
    Co-Authors: Alan G Leach, Amanda W Van Dellen, Thomas V Riecke, James S Sedinger
    Abstract:

    Lack (1967) proposed that clutch size in species with precocial young was determined by nutrients available to females at the time of egg formation; since then others have suggested that regulation of clutch size in these species may be more complex. We tested whether incubation limitation contributes to ultimate constraints on maximal clutch size in Black Brent Geese (Black Brant) Branta Bernicla nigricans. Specifically, we investigated the relationship between clutch size and duration of the nesting period (i.e. days between nest initiation and the first pipped egg) and the number of goslings leaving the nest. We used experimental clutch manipulations to assess these questions because they allowed us to create clutches that were larger than the typical maximum of five eggs in this species. We found that the per-capita probability of egg success (i.e. the probability an egg hatched and the gosling left the nest) declined from 0.81 for two-egg clutches to 0.50 for seven-egg clutches. As a result of declining egg success, clutches containing more than five eggs produced, at best, only marginally more offspring. Manipulating clutch size at the beginning of incubation had no effect on the duration of the nesting period, but the nesting period increased with the number of eggs a female laid naturally prior to manipulation, from 25.4 days (95% CI 25.1–25.7) for three-egg clutches to 27.7 days (95% CI 27.3–28.1) for six-egg clutches. This delay in hatching may result in reduced gosling growth rates due to declining forage quality during the brood rearing period. Our results suggest that the strong right truncation of Brent clutches, which results in few clutches greater than five, is partially explained by the declining incubation capacity of females as clutch size increases and a delay in hatching with each additional egg laid. As a result, females laying clutches with more than five eggs would typically gain little fitness benefit above that associated with a five-egg clutch.

  • carry over effects of winter location contribute to variation in timing of nest initiation and clutch size in black brant Branta Bernicla nigricans
    The Auk, 2012
    Co-Authors: James S Sedinger, Jason L Schamber, David H Ward
    Abstract:

    ABSTRACT. We assessed carry-over effects from winter location on timing of nest initiation and clutch size of Black Brant (Branta Bernicla nigricans) using observations of individually marked brant breeding at the Tutakoke River colony in Alaska, and wintering along a latitudinal gradient at three areas on the Pacific coast of Baja California: northernmost Bahia San Quintin (BSQ), Laguna Ojo de Liebre (LOL), and southernmost Laguna San Ignacio (LSI). Black Brant initiated nests according to a north—south trend in winter location, although year was a stronger predictor of initiation date than was wintering site. Female Black Brant that wintered at BSQ initiated nests 2.2 days earlier than females from LSI. Conversely, Black Brant showed only a weak south—north trend in clutch size; individuals from LSI laid slightly larger clutches than individuals from BSQ, probably because a smaller proportion of only high-quality females from the southernmost wintering area in Baja California were able to attain the nut...

  • timing of adult remigial wing molt in female black brant Branta Bernicla nigricans
    The Auk, 2012
    Co-Authors: Howard V Singer, James S Sedinger, Christopher A Nicolai, Amanda W Van Dellen, Brian T Person
    Abstract:

    ABSTRACT. Timing of molt is a critical life-history trait because molt is a nutritionally demanding process that must be completed before fall migration. We used data from 1992–2008 to assess hypotheses that initiation of the prebasic molt by Black Brant (Branta Bernicla nigricans) was ultimately controlled by (1) the need to complete the molt before fall migration and (2) advantages of restoring depleted nutrient reserves before growing feathers. Specifically, we expected molt to occur sooner after hatching in years when nesting was delayed (prediction 1), but we expected individuals to delay molt in relation to hatch date when nesting was earlier (prediction 2). Our rationale for prediction 1 was that the need to complete molt before fall migration is exacerbated when nesting is delayed. Prediction 2 is suggested by the advantage of restoring nutrients depleted during nesting before initiating molt. We tested predictions by assessing patterns of ninth-primary length in relation to number of days posthat...

  • carryover effects associated with winter location affect fitness social status and population dynamics in a long distance migrant
    The American Naturalist, 2011
    Co-Authors: James S Sedinger, Jason L Schamber, David H Ward, Christopher A Nicolai, Bruce Conant
    Abstract:

    AbstractWe used observations of individually marked female black brant geese (Branta Bernicla nigricans; brant) at three wintering lagoons on the Pacific coast of Baja California—Laguna San Ignacio (LSI), Laguna Ojo de Liebre (LOL), and Bahia San Quintin (BSQ)—and the Tutakoke River breeding colony in Alaska to assess hypotheses about carryover effects on breeding and distribution of individuals among wintering areas. We estimated transition probabilities from wintering locations to breeding and nonbreeding by using multistratum robust-design capture-mark-recapture models. We also examined the effect of breeding on migration to wintering areas to assess the hypothesis that individuals in family groups occupied higher-quality wintering locations. We used 4,538 unique female brant in our analysis of the relationship between winter location and breeding probability. All competitive models of breeding probability contained additive effects of wintering location and the 1997–1998 El Nino–Southern Oscillation (...

David H Ward - One of the best experts on this subject based on the ideXlab platform.

  • activity budgets daily energy expenditure and energetic model of black brant Branta Bernicla nigricans during winter and spring along the lower alaska peninsula
    Wildfowl, 2019
    Co-Authors: Bryan L Daniels, David H Ward, Jeffrey M Black
    Abstract:

    Black Brant Branta Bernicla nigricans have one of the most specialised of goose diets during the non-breeding season, utilising coastal habitats to up-end and feed on dense beds of intertidal Common Eelgrass Zostera marina. Past studies suggested that Black Brant may not reach energetic requirements during diurnal foraging on eelgrass beds and must use alternate, less energetically beneficial foraging strategies ( e.g . searching for and consuming sparse drifting eelgrass and night-time eelgrass bed foraging) to meet energy demands. Time-activity budgets and daily energy expenditure (DEE) were quantified and use of alternate foraging strategies during periods of limited food availability were described for Black Brant along the Lower Alaska Peninsula in Kinzarof and Izembek Lagoons during winter (February–March) and spring (April–May) 2011. Based on 577 instantaneous flock scans across seasons and tide stages, predominant Black Brant activities were vigilance (41%), foraging (33%), comfort (16%) and locomotion (8%). Estimated mean DEE across months and locations was 1,181 ± 110 kJ/day. Flight costs accounted for an estimated 23–46% of expended energy in winter and spring, roosting 22–27%, thermoregulatory costs 13–18%, foraging 8–15% and vigilance 10–17% in spring. Black Brant only met daily energetic requirements by employing alternate foraging strategies, particularly nocturnal foraging, which offset their DEE by 21–43% in winter and 17–28% in spring.

  • patrones de uso de sitios naturales y artificiales por Branta Bernicla nigricans anseriformes anatidae en guerrero negro baja california sur mexico
    Revista De Biologia Tropical, 2013
    Co-Authors: Israel Martinez Cedillo, David H Ward, Roberto Carmona, Gustavo D Danemann
    Abstract:

    Habitat use patterns of the Black Brant Branta Bernicla nigricans (Anseriformes: Anatidae) in natural and artificial areas of Guerrero Negro, Baja California Sur, Mexico. The Black Brant is a common inhabitant of the Western Artic American tundra, which migrates to Southern Pacific coasts during the winter season. Approximately, 31 000 birds (31%) constitute the Mexican population of Brants at Guerrero Negro, Ojo de Liebre, and Exportadora de Sal lagoon complex; nevertheless, there is little information about the distribution patterns and zone usage. At Guerrero Negro Lagoon (GNL), Ojo de Liebre Lagoon (OLL, both natural sites), and at Exportadora de Sal (ESSA, artificial site) we determined by monthly censuses (from November 2006 to April 2007, 08:00-16:00h) and observed: (1) season and site effects on population structure (age groups), and (2) the tide level relationship with the abundance and proportion of feeding birds. Within a total of 150 observa- tion hours and 98 birds, our results showed a general 0.68 proportion of adults, that was higher in winter than in spring. The statistics analysis showed no effects by site on the proportion of feeding birds, but we observed a temporal decrease at ESSA and at GNL. In contrast the proportion of feeding birds at OLL was constant. We observed an increase in the juveniles between winter and spring. This increase is related with the differential migration, which mentions that the juveniles are the last to leave the wintering area. In winter the relations of the tide level with the abundance of Brant were: direct at ESSA, inverse at OLL and no relation found at GNL. In spring, no relation was observed in the sites. The proportion of Brants feeding at OLL (the site with the higher abundance) was independent of the tide level. This is related with two possible behaviors of the geese: (1) they can move through the lagoon and take advantage of the tidal lag, which is up to four hours; and (2) they can modify their feeding strategies, more on floating eelgrass (Zostera marina). Rev. Biol. Trop. 61 (2): 927-935. Epub 2013 June 01.

  • foraging home ranges of black brant Branta Bernicla nigricans during spring stopover at humboldt bay california usa
    Wildfowl, 2013
    Co-Authors: Jeffrey M Black, David H Ward
    Abstract:

    Foraging home ranges of Black Brant Branta Bernicla nigricans (n = 8) were quantified to determine proportional use of available intertidal habitat during spring migration stopover at Humboldt Bay, California, USA. The average foraging range area was 232 ha (s.d. ± 156 ha) of which 114 ha (s.d. ± 43 ha) was comprised of their primary food, eelgrass Zostera marina; the other habitats included mudflat/sandbar and deep water channels. This amounted to individuals using an average of 16% of the available eelgrass in the bay (716 ha). Potential consequences are discussed for Black Brant remaining faithful to a relatively small proportion of available habitat. Individual Black Brant may employ different foraging strategies in different parts of Humboldt Bay to obtain nutrients and body stores to fuel migration and subsequent breeding.

  • migration patterns of western high arctic grey belly brant Branta Bernicla
    Wildfowl, 2013
    Co-Authors: Sean W Boyd, David H Ward, Donald K Kraege, Alyssa A Gerick
    Abstract:

    This study describes the seasonal migration patterns of Western High Arctic Brant (WHA, or Grey-belly Brent Geese), Branta Bernicla , an admixed population that breeds in the Canadian High Arctic and winters along the Pacific coast of North America. Adult WHA Brant were captured in family groups on Melville Island (75°23’N, 110°50’W) in 2002 and 2005 and marked with satellite platform transmitting terminal (PTT) transmitters or very high frequency (VHF) transmitters. During autumn migration, all PTT-tagged Brant followed a coastal route around Alaska and staged for variable lengths of time at the following sites on the north and west coasts of Alaska: Kasegaluk Lagoon (69°56’N, 162°40’W), Ikpek Lagoon (65°55’N, 167°03’W), and Izembek Lagoon (55°19’N, 162°50’W). Izembek Lagoon was the most important staging area in terms of length of stay (two months on average) and the majority (67–93%) of PTT and VHF detections occurred in Moffet Bay (55°24’N, 162°34’W). After departing Izembek Lagoon, the PTT-tagged geese followed a c. 2,900 km trans-oceanic route to overwinter in the southern part of the Salish Sea (i.e. from north Puget Sound, Washington to south Strait of Georgia, British Columbia; centred at c. 48°45’N, 122°40’W). Most (c. 45%) PTT detections in the southern Salish Sea occurred in Samish Bay (48°36’N, 122°30’W) followed by Padilla Bay (48°30’N, 122°31’W; c. 26%). Brant migrated north from the Salish Sea along the coast to southeast Alaska and then followed either an interior route across the Yukon or a coastal route around Alaska. The “interior” birds staged for c. four days at Liverpool Bay (69°20’N, 133°55’W) in the Northwest Territories before flying on to Melville Island. They also departed the Salish Sea two weeks later than the coastal migrants and arrived at Melville Island two weeks earlier. This study and previous research suggest that WHA Brant use similar migration routes each year and are faithful to their breeding, staging, and wintering grounds. Because WHA Brant constitute one of the smallest breeding stocks in the world (8,000–11,000 individuals), concentrate in only a few areas, and are likely highly site-faithful, they are susceptible to a range of threats such as excessive harvesting, habitat loss and/or degradation, and petroleum spills.

  • carry over effects of winter location contribute to variation in timing of nest initiation and clutch size in black brant Branta Bernicla nigricans
    The Auk, 2012
    Co-Authors: James S Sedinger, Jason L Schamber, David H Ward
    Abstract:

    ABSTRACT. We assessed carry-over effects from winter location on timing of nest initiation and clutch size of Black Brant (Branta Bernicla nigricans) using observations of individually marked brant breeding at the Tutakoke River colony in Alaska, and wintering along a latitudinal gradient at three areas on the Pacific coast of Baja California: northernmost Bahia San Quintin (BSQ), Laguna Ojo de Liebre (LOL), and southernmost Laguna San Ignacio (LSI). Black Brant initiated nests according to a north—south trend in winter location, although year was a stronger predictor of initiation date than was wintering site. Female Black Brant that wintered at BSQ initiated nests 2.2 days earlier than females from LSI. Conversely, Black Brant showed only a weak south—north trend in clutch size; individuals from LSI laid slightly larger clutches than individuals from BSQ, probably because a smaller proportion of only high-quality females from the southernmost wintering area in Baja California were able to attain the nut...

Barwolt S Ebbinge - One of the best experts on this subject based on the ideXlab platform.

  • a multifactorial explanation for variation in breeding performance of brent geese Branta Bernicla
    Ibis, 2008
    Co-Authors: Barwolt S Ebbinge
    Abstract:

    The dramatic differences in annual breeding success of Dark-bellied Brent Geese Branta b. Bernicla are generally interpreted as being caused by variable conditions on the arctic breeding grounds. The recently revived discussion on this issue mentions, in particular, the cyclic variation in abundance of lemmings, resulting in cyclic variation of predation pressure on bird nests by arctic foxes, as the main factor determining whether Brent Geese are able to breed successfully or not. New data on the spring condition of Brent Geese in Western Europe and wind conditions during migration from the spring staging areas to the breeding grounds show that these factors also influence breeding output.

  • brent goose Branta Bernicla Bernicla feeding behaviour during incubation taimyr peninsula russia
    Polar Biology, 2007
    Co-Authors: Maud Poisbleau, Herve Fritz, Sebastien Dalloyau, Charlesandre Bost, Barwolt S Ebbinge
    Abstract:

    Incubating birds must balance the time and the energy invested in incubation with the energy acquisition for their survival. Many factors such as weather and predation influence this trade-off. In Arctic geese, only females incubate, and they leave the nest regularly to feed while males invest in keeping their nests and mates safe. This study conducted on Big Bird Island (Taimyr Peninsula) during the summer of 2004 examined the incubation behavior of dark-bellied brent geese Branta Bernicla Bernicla to assess the effect of date, period of day and weather conditions on the incubation and feeding behaviors of females and males. Females were at their nests only for 65% of the total time observed. This very low value, compared to other goose species, could be the result of the combined effects of good weather conditions, low predation pressure and opportunities to feed close to the nest. We found differential adjustments of male and female behaviors. Females appeared to focus on the trade-off between feeding and incubating, in relation to weather conditions, and on their own energy balance. Males appeared to respond primarily by the absence of the female from their nest.

  • changes in body mass and hormone levels between wintering and spring staging areas in dark bellied brent geese Branta Bernicla Bernicla
    Journal of Avian Biology, 2006
    Co-Authors: Maud Poisbleau, Herve Fritz, Marcel M Lambrechts, Colette Trouve, Barwolt S Ebbinge
    Abstract:

    We document seasonal changes in body mass and plasma hormone levels (testosterone and triiodothyronine) between winter and spring quarters in dark-bellied brent geese Branta Bernicla Bernicla. Body mass increased between winter and spring, whereas body size was the same for the birds sampled in winter and those in spring. Adults and males were larger and heavier than juveniles and females. Plasma testosterone levels did not differ significantly between winter and spring, and did not vary with sex, age and morphometry. Plasma triiodothyronine (T3) levels were significantly higher in spring than in winter, and were higher for males than for females. However, T3 levels did not vary significantly with age and body measurements. To explain the findings, we discuss potential impacts of social dominance

  • dark bellied brent geese Branta Bernicla Bernicla as recorded by satellite telemetry do not minimize flight distance during spring migration
    Ibis, 2002
    Co-Authors: Martin Green, Preben Clausen, Thomas Alerstam, Rudi Drent, Barwolt S Ebbinge
    Abstract:

    Nine Dark-bellied Brent Geese Branta Bernicla Bernicla were equipped with satellite transmitters during spring staging in the Dutch Wadden Sea in 1998 and 1999. The transmitters (in all cases less than 3% of body mass) were attached to the back by a flexible elastic harness. One juvenile female was tracked to the Yamal peninsula in 1998. Eight adult males were selected from a single catch of 75 to span the range of body mass observed on the date of capture (11 May 1999) and all but the lightest individual completed the first lap of the migratory flight to the White Sea, Russia, according to the time schedule normal for this species. Six birds were successfully tracked to Taymyr for a total distance averaging 5004 km (range 4577-5164) but judging from later movements none bred (although 1999 was breeding year). Although the routes chosen during spring migration were closely similar; none of the tagged birds migrated together. On average the geese used 16 flights to reach their summer destinations on Taymyr. The longest uninterrupted flights during the first half of the journey (Wadden Sea to Kanin) covered 1056 km (mean of seven adult males, range 768-1331), while the corresponding value for the second half of the migration (Kanin-Taymyr) was only 555 km (mean of six adult males). Only 7% of total time during spring migration was spent in active flight, as contrasted to c. 80% at long-term stopovers. Overall average travelling speed was 118 km/day (range 97-148). Including fattening prior to departure the rate of travel falls to 62 km/day (range 49-70), in keeping with theoretical predictions. Routes followed deviated from the great circle route, adding at least 700 km (16%) to the journey from Wadden Sea to Taymyr, and we conclude that the coastal route is chosen to facilitate feeding, drinking and resting en route instead of minimizing total flight distance.

Preben Clausen - One of the best experts on this subject based on the ideXlab platform.

  • Mark–resight approach as a tool to estimate population size of one of the world's smallest goose populations
    Bird Study, 2013
    Co-Authors: Kevin Kuhlmann Clausen, Casper Caesar Faelled, Preben Clausen
    Abstract:

    Capsule The present study investigates the use of a mark–resight procedure to estimate total population size in a local goose population. Using colour-ring sightings of the increasingly scattered population of Light-bellied Brent Geese Branta Bernicla hrota from their Danish staging areas, we estimate a total population size of 7845 birds (95% CI: 7252–8438). This is in good agreement with numbers obtained from total counts, emphasizing that this population, although steadily increasing, is still small compared with historic numbers.

  • foraging range habitat use and minimum flight distances of east atlantic light bellied brent geese Branta Bernicla hrota in their spring staging areas
    Wildfowl, 2013
    Co-Authors: Kevin Kuhlmann Clausen, Preben Clausen, Jens Peder Hounisen, Marie S Vissing
    Abstract:

    Global Positioning System (GPS) satellite telemetry was used to determine the foraging range, habitat use and minimum flight distances for individual East Atlantic Light-bellied Brent Geese Branta Bernicla hrota at two spring staging areas in Denmark. Foraging ranges (mean ± s.d. = 53.0 ± 23.4 km2) were comparatively large, greater than reported elsewhere for this species, and habitat use revealed a high exploitation of salt marshes (64.4%), which now replace traditional fjord habitats as the most important for spring-fattening. At one site (Agero), geese had started to exploit agricultural fields (winter-sown cereals; 11.8% of the total GPS location data), and in all areas fjords were still frequently used for roosting at night. Minimum flight distances for foraging excursions at the staging sites varied considerably between individual geese (ranging from 4.64–10.14 km/day), and these were related to differences in habitat use. Geese using a high proportion of agricultural areas flew greater distances than those avoiding this habitat. Compared to historical data on the same population, these findings indicate a significant enlargement of foraging ranges and increased use of terrestrial habitats. This might reflect changes in habitat availability, and is probably related to significant declines in Common Eelgrass Zostera marina in both these areas. From a historically rather sedentary lifestyle, which centred around foraging on Zostera beds in fjord habitats, this population now feeds on scattered areas of salt marsh, and increasingly on inland winter-sown cereals, in a progressively cultivated landscape. As fjord habitats remain the preferred roosting areas (probably as a consequence of differences in perceived habitat-specific predation risk), this “terrestrialisation” of Brent Goose habitat use is associated with increased energetic costs in the form of higher minimum flight distances.

  • the netherlands as a winter refuge for light bellied brent geese Branta Bernicla hrota
    Wildfowl, 2013
    Co-Authors: Kees Koffijberg, Erik Van Winden, Preben Clausen
    Abstract:

    From 1978/79 onwards, eleven influxes of East Atlantic Light-bellied Brent Geese  Branta Bernicla hrota were recorded in the Netherlands, to the south of their regular wintering areas in northern Denmark and northeast England. During most influxes,  c. 3–6% of the total population occurred in the Netherlands, but large influxes in 1995/96 and 2010/11 involved as many as 800–907 individuals, i.e. 18% and 11% of the flyway population respectively. Core wintering sites within the Netherlands were in the southwest Wadden Sea, in the northern part of Noord-Holland and in the Delta area in the southwest of the country. The first two of these areas are thought to have been more regular wintering areas for Light-bellied Brent Geese in the first part of the 20th century, although good documentation on numbers is lacking. The highest number recorded at a single site was 245 birds in Polder Kimswerd/Eendracht, Friesland, in December 2010. The distribution pattern was similar during all influxes, indicating traditional site use by the wintering flocks. Winters with peak numbers in the Netherlands show a significant, negative correlation with average daily temperatures at the Danish wintering sites. During prolonged and/or heavy cold spells, feeding conditions in Denmark deteriorate due to ice- or snow cover, making both aquatic and agricultural food resources unavailable and forcing birds to depart; this was confirmed by count data from Denmark. In 1995/96, phenological patterns and sightings of marked birds also indicated an influx from birds from the wintering site at Lindisfarne in the UK, but this could not be confirmed for more recent winters. Sightings of marked birds showed that at least some birds (eight out of 34 observed individuals) were involved in successive influxes; in non-influx years they were seen regularly at wintering sites further up the flyway as well as on breeding sites at Svalbard. The regular patterns of influxes, the traditional use of particular sites during influx years and repeated observations of the same individuals at these sites (which may transfer knowledge of alternative wintering sites in the Netherlands to their offspring, indicated by ringed birds being seen with their goslings) illustrates that the Netherlands should be considered as a regular hard weather winter refuge for the sub-species. Appropriate measures therefore should be taken to include these sites within the national Natura 2000 network.

  • energetic consequences of a major change in habitat use endangered brent geese Branta Bernicla hrota losing their main food resource
    Ibis, 2012
    Co-Authors: Kevin Kuhlmann Clausen, Preben Clausen, Casper Caesar Faelled, Kim N Mouritsen
    Abstract:

    Coastal seagrasses are declining at increasing rates worldwide, forcing herbivores previously reliant on these habitats to abandon them in search of alternative ways to fulfil their daily energy budgets. After two decades of declining seagrass abundance in Mariager Fjord, Denmark, the Svalbard breeding population of Light-bellied Brent Geese Branta Bernicla hrota has experienced substantial changes in habitat use at this traditional autumn staging area. Declines in seagrasses have caused birds to depend increasingly on Sea Lettuce Ulva lactuca in recent years, and forced birds into terrestrial habitats such as saltmarsh and winter wheat. In contrast to those birds exploiting aquatic habitats, birds relying on these new habitats showed higher energy expenditure and failed to balance their energy budget. Eelgrass (Zostera) was energetically superior to other food resources, with marine Ulva being second best. Predicted body mass development under two different scenarios indicate that present habitat use resulted in a midwinter body mass around 122 g lower than just 20 years ago, equivalent to c. 9.4% of Brent Goose body weight. Even after controlling for inter-annual differences in thermoregulatory costs, the effect of changes in habitat use translated into a body mass reduction of c. 56 g, which could adversely affect survival and future reproduction. Flyway-wide declines in Zostera abundance and further reductions in traditional habitats due to climate change give cause to reassess projected population trends and consequent management implications for the East Atlantic flyway population of Light-bellied Brent Geese.

  • Light-bellied brent geese Branta Bernicla hrota compensate for wind drift when flying over open sea
    2012
    Co-Authors: Martin Green, Thomas Alerstam, Preben Clausen
    Abstract:

    Light-bellied brent geese Branta Bernicla hrota compensate for wind drift when flying over open sea

Mark S Lindberg - One of the best experts on this subject based on the ideXlab platform.

  • fidelity and breeding probability related to population density and individual quality in black brent geese Branta Bernicla nigricans
    Journal of Animal Ecology, 2008
    Co-Authors: James S Sedinger, David H Ward, Nathan D Chelgren, Mark S Lindberg
    Abstract:

    Summary 1 Patterns of temporary emigration (associated with non-breeding) are important components of variation in individual quality. Permanent emigration from the natal area has important implications for both individual fitness and local population dynamics. 2 We estimated both permanent and temporary emigration of black brent geese (Branta Bernicla nigricans Lawrence) from the Tutakoke River colony, using observations of marked brent geese on breeding and wintering areas, and recoveries of ringed individuals by hunters. We used the likelihood developed by Lindberg, Kendall, Hines & Anderson 2001 (Combining band recovery data and Pollock's robust design to model temporary and permanent emigration. Biometrics, 57, 273–281) to assess hypotheses and estimate parameters. 3 Temporary emigration (the converse of breeding) varied among age classes up to age 5, and differed between individuals that bred in the previous years vs. those that did not. Consistent with the hypothesis of variation in individual quality, individuals with a higher probability of breeding in one year also had a higher probability of breeding the next year. 4 Natal fidelity of females ranged from 0·70 ± 0·07–0·96 ± 0·18 and averaged 0·83. In contrast to Lindberg et al. (1998), we did not detect a relationship between fidelity and local population density. Natal fidelity was negatively correlated with first-year survival, suggesting that competition among individuals of the same age for breeding territories influenced dispersal. Once females nested at the Tutakoke River, colony breeding fidelity was 1·0. 5 Our analyses show substantial variation in individual quality associated with fitness, which other analyses suggest is strongly influenced by early environment. Our analyses also suggest substantial interchange among breeding colonies of brent geese, as first shown by Lindberg et al. (1998).

  • life history implications of large scale spatial variation in adult survival of black brant Branta Bernicla nigricans
    The Auk, 2002
    Co-Authors: James S Sedinger, Mark S Lindberg, Nathan D Chelgren, Tim Obritchkewitch, Morgan T Kirk, Philip Martin, Betty A Anderson, David H Ward
    Abstract:

    Abstract We used capture–recapture methods to estimate adult survival rates for adult female Black Brant (Branta Bernicla nigricans; hereafter “brant”) from three colonies in Alaska, two on the Yukon-Kuskokwim Delta, and one on Alaska's Arctic coast. Costs of migration and reproductive effort varied among those colonies, enabling us to examine variation in survival in relation to variation in these other variables. We used the Barker model in program MARK to estimate true annual survival for brant from the three colonies. Models allowing for spatial variation in survival were among the most parsimonious models but were indistinguishable from a model with no spatial variation. Point estimates of annual survival were slightly higher for brant from the Arctic (0.90 ± 0.036) than for brant from either Tutakoke River (0.85 ± 0.004) or Kokechik Bay (0.86 ± 0.011). Thus, our survival estimates do not support a hypothesis that the cost of longer migrations or harvest experienced by brant from the Arctic reduced t...

  • Life-History Implications of Large-Scale Spatial Variation in Adult Survival of Black Brant (Branta Bernicla Nigricans)
    The Auk, 2002
    Co-Authors: James S Sedinger, Mark S Lindberg, Nathan D Chelgren, Tim Obritchkewitch, Morgan T Kirk, Philip Martin, Betty A Anderson, David H Ward
    Abstract:

    Abstract We used capture–recapture methods to estimate adult survival rates for adult female Black Brant (Branta Bernicla nigricans; hereafter “brant”) from three colonies in Alaska, two on the Yukon-Kuskokwim Delta, and one on Alaska's Arctic coast. Costs of migration and reproductive effort varied among those colonies, enabling us to examine variation in survival in relation to variation in these other variables. We used the Barker model in program MARK to estimate true annual survival for brant from the three colonies. Models allowing for spatial variation in survival were among the most parsimonious models but were indistinguishable from a model with no spatial variation. Point estimates of annual survival were slightly higher for brant from the Arctic (0.90 ± 0.036) than for brant from either Tutakoke River (0.85 ± 0.004) or Kokechik Bay (0.86 ± 0.011). Thus, our survival estimates do not support a hypothesis that the cost of longer migrations or harvest experienced by brant from the Arctic reduced their annual survival relative to brant from the Yukon-Kuskokwim Delta. Spatial variation in survival provides weak support for life-history theory because brant from the region with lower reproductive investment had slightly higher survival.

  • natal and breeding philopatry in a black brant Branta Bernicla nigricans metapopulation
    Ecology, 1998
    Co-Authors: Mark S Lindberg, James S Sedinger, Dirk V Derksen, Robert F Rockwell
    Abstract:

    We estimated natal and breeding philopatry and dispersal probabilities for a metapopulation of Black Brant (Branta Bernicla nigricans) based on observations of marked birds at six breeding colonies in Alaska, 1986–1994. Both adult females and males exhibited high (>0.90) probability of philopatry to breeding colonies. Probability of natal philopatry was significantly higher for females than males. Natal dispersal of males was recorded between every pair of colonies, whereas natal dispersal of females was observed between only half of the colony pairs. We suggest that female-biased philopatry was the result of timing of pair formation and characteristics of the mating system of brant, rather than factors related to inbreeding avoidance or optimal discrepancy. Probability of natal philopatry of females increased with age but declined with year of banding. Age-related increase in natal philopatry was positively related to higher breeding probability of older females. Declines in natal philopatry with year of banding corresponded negatively to a period of increasing population density; therefore, local population density may influence the probability of nonbreeding and gene flow among colonies.

  • environmental influence on life history traits growth survival and fecundity in black brant Branta Bernicla
    Ecology, 1995
    Co-Authors: James S Sedinger, Paul L Flint, Mark S Lindberg
    Abstract:

    We studied relationships between body size of female Black Brant goslings (Branta Bernicla nigricans) late in their growth period and first year survival, eventual adult body size, breeding propensity, and size and volume of clutches they eventually produced to examine the relationship between growth and fitness in this population. We indexed body size by calculating PC1 scores based on either culmen and tarsus, or culmen, tarsus, and mass. Gosling (PC scores based on culmen and tarsus) size was positively correlated with resighting rate (P = 0.005), indicating that larger goslings survived at a higher rate than did smaller goslings. Gosling size was correlated with adult size of the same individuals (P = 0.0004). Larger goslings were more likely to breed as 2- or 3-yr-olds than were medium or small goslings (P = 0.008). Larger adult brant laid more eggs (P = 0.03) and produced clutches with greater total volume (P = 0.03) than did smaller brant. Given the important role of foraging environment in growth of goslings, these data suggest an important role of early environment in determining life-history traits.