scholarly journals Feeding Ecology of Canada Geese (Branta Canadensis Interior) in Sub-Arctic Inland Tundra During Brood-Rearing

The Auk ◽  
2005 ◽  
Vol 122 (1) ◽  
pp. 144-157 ◽  
Author(s):  
Marie-Christine Cadieux ◽  
Gilles Gauthier ◽  
R. John Hughes

AbstractThe diet of adult Canada Geese (Branta canadensis interior) and their goslings was determined during the brood-rearing season in a freshwater tundra habitat using esophageal contents from 25 adult females, 27 adult males, and 59 goslings. Habitat use by geese and the availability and quality of aboveground biomass in wet sedge meadows and around ponds in lichen-heath tundra were also evaluated throughout the summer. During the first four weeks of brood-rearing, adult Canada Geese ate primarily graminoids (>65%), especially leaves of the short form of Carex aquatilis and Eriophorum spp., which had the highest nitrogen concentration (2.5–3.5%). Although graminoids were also important for goslings, they consumed a greater variety of other plant species (68%) than adults, especially in the first two weeks, possibly because of their inexperience. Late in the brood-rearing period, as the nitrogen concentration of graminoid plants declined, adults shifted to a diet composed mainly of berries (>40%, mostly Empetrum nigrum). At that time, goslings consumed fewer berries (24%) and maintained a higher proportion of nitrogen-rich plants in their diet (53% leaves, mostly graminoids) than adults, presumably to complete their growth. Plant species consumed by geese over the summer indicated a preference for high-quality plants (i.e. those with a high nitrogen concentration). Consequently, wet sedge meadow, the habitat that offered plant species of highest quality, was the habitat most heavily used throughout the summer, particularly around peak hatch. Goose grazing had no effect on seasonal production of aboveground biomass of graminoids, probably because of the relatively low density of the goose population.Écologie alimentaire de Branta canadensis interior pendant la période d’élevage des jeunes dans un milieu d’eau douce sub-arctique

2015 ◽  
Vol 129 (3) ◽  
pp. 229
Author(s):  
Richard C. Cotter

The Atlantic population of Canada Geese (Branta canadensis) nests in the coastal lowlands of eastern Hudson Bay and southwestern Ungava Bay in Nunavik, Quebec. Although many aspects of the nesting ecology of this and other northern populations of Canada Geese have been studied and published, there is a paucity of information on the use of brood-rearing and moulting sites. Based on 18 years of band and recapture data from an ongoing banding program, this paper presents the distribution of brood-rearing and moulting sites and the use of these sites over time. Along Hudson Bay and Ungava Bay, the most important brood-rearing and moulting areas are the stretch of coastal lowlands between the Mariet River and Shallow Bay and between Rivière aux Feuilles and Virgin Lake, respectively. Of all adult geese captured during the banding program (n = 41 924), 7.5% (standard error [SE] 0.13%) were recaptures, that is, birds that had previously been caught and banded; annual recapture rates ranged from 5.1% to 11.4%. The mean and median distances between the site of first recapture and the original site of capture were 4.3 km (SE 0.22 km) and 1.5 km, respectively. Juveniles moved, on average, 5.4 km farther than adults and males moved 1.4 km farther than females. Among geese banded as juveniles, males moved twice as far as females: 11.5 km versus 5.7 km.


1976 ◽  
Vol 54 (5) ◽  
pp. 634-643 ◽  
Author(s):  
Sherwin S. Desser ◽  
Andrée K. Ryckman

The development of Leucocytozoon simondi was studied in naturally and experimentally infected Branta canadensis maxima, Branta canadensis interior, and Anser domesticus. The number of mature round gametocytes in the peripheral blood of the Canada geese increased between days 9 and 15 post exposure (PE) and decreased rapidly thereafter. Mean peak parasitemias recorded on day 13 PE were (per 1000 red blood cells (RBC)): 8 gametocytes in B.c. maxima, 16 gametocytes in B.c. interior, and 17 gametocytes in A. domesticus. About 3 weeks PE, gametocytes disappeared from the peripheral circulation and were not observed again during the autumn, winter, and spring in birds kept in the laboratory.Haematocrit determinations in the Canada geese revealed a low fluctuating anemia during the primary infection which subsided by day 21 PE. A more severe anemia was recorded in A. domesticus with a mean low packed RBC value of about 18% on day 11 PE. Immature and mature hepatic schizonts were observed in the Canada and domestic geese between days 3 and 8 PE. Neither megaloschizonts nor elongate gametocytes were seen. Clinical signs, pathology, and mortality commonly associated with L. simondi infection in ducks were not observed. Hypotheses are advanced to explain reports of severe pathogenesis associated with L. simondi infections in Canada geese in other localities.


2005 ◽  
Vol 119 (4) ◽  
pp. 483
Author(s):  
Mark L. Mallory ◽  
Alain J. Fontaine ◽  
Hugh Boyd

The accepted breeding distribution of Canada Geese from the Atlantic Population (Branta canadensis interior) in the eastern Canadian Arctic is currently confined to northern Québec and the south coast of Baffin Island. Here we provide evidence based on observations from scientific studies, Inuit hunters, and territorial Wildlife Officers that B. c. interior now breeds in growing numbers 500 km farther north on northeastern Baffin Island than previously reported. Cackling Geese (B. hutchinsii), which breed more widely across eastern Arctic Canada, to about 72°N, may also be increasing there. Moreover, individuals of both species are seen occasionally as far north as Ellesmere Island in small flocks and within migrating or moulting flocks of Snow Geese (Chen caerulescens) or Brant (B. bernicla hrota), though none of these far northern stragglers are known to have bred. Whether these observations reflect a recent range expansion or improved distributional knowledge from more intensive recent survey efforts remains unknown.


1994 ◽  
Vol 72 (3) ◽  
pp. 533-540 ◽  
Author(s):  
Laura M. Seddon ◽  
Thomas D. Nudds

Competing hypotheses that have been advanced to explain the phenomenon of posthatch brood mixing by waterfowl can be distinguished by whether they assume that adults experience costs in rearing nidifugous offspring. To test this, time budget data were collected for giant Canada geese (Branta canadensis maxima) at Cambridge, Ontario, in 1990. Breeding adults with broods devoted more time to vigilance (p = 0.001) and less time to feeding (p = 0.001) than adults that hatched clutches but were without broods, suggesting a cost to rearing nidifugous young. However, as goslings matured, parents allocated less time to vigilance (p < 0.001) and more time to locomotion (p = 0.005), and time spent feeding did not change (p = 0.336). In addition, brood size did not affect the time parents allocated to vigilance (p = 0.543) or feeding (p = 0.727), suggesting that caring for additional young has negligible effects on parents. Goslings were selective about the adult with which they associated (they were positioned closer to females than to males), but neither brood size nor brood age affected the feeding time of goslings (p = 0.94 and 0.76, respectively) or time spent vigilant (p = 0.22 and 0.69, respectively), suggesting that goslings gained no obvious advantage from greater foraging opportunities or better predator detection by congregating in larger broods.


1985 ◽  
Vol 63 (8) ◽  
pp. 1765-1772 ◽  
Author(s):  
S. K. Mainguy ◽  
V. G. Thomas

Changes in proximate body composition were analyzed in nonmigratory giant Canada geese (Branta canadensis maxima) from Toronto, Ont. (43°37′N, 79°20′W), collected during early and late egg laying in 1980 and 1981, and during incubation and moult in 1981. Early nesting geese had more fat, though not more protein, than late nesting birds in both years. Geese collected in 1981 had more fat and protein than geese collected in 1980. Early and late laying females in both years lost on average 198 g (26%) of fat and 34 g (5%) of protein from the beginning to the end of laying. Fifty-eight percent of the fat reserves possessed at the beginning of laying were lost during incubation. Fat reserves of prelaying Branta canadensis interior nesting on the James Bay lowland (53°15′N, 82°09′W) in 1980 were 9% greater than those of B. c. maxima nesting in Southern Ontario. During the moult at Toronto, Canada geese lost weight from flight muscles while gaining weight in other muscles and in fat. This pattern is seen in waterfowl moulting at several latitudes, and indicates that geese moulting in both southern and northern latitudes probably rely on nutrients in food rather than in body tissues to supply growing feathers.


The Condor ◽  
2004 ◽  
Vol 106 (2) ◽  
pp. 288-298
Author(s):  
Timothy D. Bowman ◽  
Robert A. Stehn ◽  
Kim T. Scribner

Abstract Glaucous Gulls (Larus hyperboreus) nesting on the Yukon-Kuskokwim (Y-K) Delta frequently prey on juvenile waterfowl. We collected 434 Glaucous Gulls from late June to early August 1994 to examine diet. Identification of undigested prey tissue, based on DNA microsatellite loci, showed three species of goslings in gull stomachs: Emperor Goose (Chen canagica), White-fronted Goose (Anser albifrons), and Cackling Canada Goose (Branta canadensis minima). Gulls that nested inland and were collected >1.6 km from the coast accounted for approximately 70% of the total gull predation on Emperor and Canada Geese, and 96% on White-fronted Geese. Our stratified sample of gull stomachs and aerial survey estimates of population size and distribution of gulls and juvenile geese enabled extrapolation of species-specific predation rates to the entire Y-K Delta. We estimated that a minimum of 21 000 Emperor Goose, 34 000 Canada Goose, and 16 000 White- fronted Goose goslings were consumed by 12 600 Glaucous Gulls during the brood-rearing period on the Y-K Delta in 1994. Minimum estimated take by gulls represented 33% of Cackling Canada Goose, 47% of Emperor Goose, and 39% of White-fronted Goose eggs estimated to have hatched in the same area as gull collections. Gulls selected the three species of geese approximately in proportion to their abundance. Although gull predation caused significant gosling mortality, its role in regulating goose populations on Y-K Delta remains unresolved. Depredación de Pichones de Gansos por Gaviotas Larus hyperboreus en el Delta del Yukon-Kuskokwim, Alaska Resumen. Las gaviotas Larus hyperboreus que nidifican en el delta del Yukon-Kuskokwim (Y-K) depredan aves acuáticas juveniles con frecuencia. Para examinar su dieta, colectamos 434 gaviotas de esta especie entre finales de junio y principios de agosto de 1994. Identificamos los tejidos de presas no digeridos con base en loci de ADN microsatelital y encontramos pichones de tres especies de gansos (Chen canagica, Anser albifrons y Branta canadensis minima) en los estómagos de las gaviotas. Las gaviotas que estaban nidificando tierra adentro y que fueron colectadas a más de 1.6 km de la costa representaron aproximadamente el 70% del total de las depredaciones de C. canagica y B. canadensis y el 96% de las de A. albifrons. Nuestra muestra estratificada de estómagos de gaviotas, junto con estimaciones del tamaño poblacional de las gaviotas y gansos juveniles hechas mediante censos desde el aire, permitieron hacer extrapolaciones de tasas de depredación especie- específicas para todo el delta Y-K. Los números estimados mínimos de pichones depredados por 12 600 gaviotas en el delta durante el período de cría de 1994 fueron 21 000 C. canagica, 34 000 B. canadensis y 16 000 A. albifrons. Estimamos que en lás áreas en que fueron colectadas, las gaviotas consumieron como mínimo el 33%, 47% y 39% del número estimado de huevos allí eclosionados de B. canadensis, C. canagica y A. albifrons, respectivamente. Las gaviotas seleccionaron a las tres especies de gansos aproximadamente en proporción a su abundancia. Aunque la depredación por gaviotas causó una mortalidad significativa de los pichones, aún debe determinarse su papel en la regulación de las poblaciones de gansos en el delta Y-K.


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