Effects of simulated feeding by snow geese on Scirpus americanus rhizomes

We investigated whether repeated intensive grazing of rhizomes of three-square bulrush (Scirpus americanus) by greater snow geese (Chen caerulescens atlantica) staging in a tidal brackish marsh along the St. Lawrence River in Québec can induce changes in the nutritional value and structural characteristics of the rhizomes. We compared rhizomes growing on heavily used sites with those growing in ungrazed sites (exclosures) for 3 years. The belowground standing crop of S. americanus was greater in ungrazed than in grazed plots, but no difference was observed in the nutritional constituents (nitrogen and fiber) of rhizomes between the two types of plot. Moreover, S. americanus did not increase the deposition of phenolics (chemical defense) in its rhizomes following grazing. Our results lead us to conclude that goose grubbing decreases quantity without affecting quality of S. americanus rhizomes.

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Recovery of tall cotton-grass following real and simulated feeding by snow geese

Ecography ◽

10.1111/j.1600-0587.2000.tb00293.x ◽

2000 ◽

Vol 23 (3) ◽

pp. 367-373 ◽

Cited By ~ 3

Author(s):

J. W. Hupp ◽

D. G. Robertson ◽

J. A. Schmutz

Keyword(s):

Snow Geese ◽

Simulated Feeding

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Is there an Optimal Clutch Size in Snow Geese?

The American Naturalist ◽

10.1086/284751 ◽

1987 ◽

Vol 130 (6) ◽

pp. 839-863 ◽

Cited By ~ 32

Author(s):

R. F. Rockwell ◽

C. S. Findlay ◽

F. Cooke

Keyword(s):

Clutch Size ◽

Snow Geese ◽

Optimal Clutch Size

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Temporal Changes in Habitat Selection and Nest Spacing in a Colony of Ross' and Lesser Snow Geese

The Auk ◽

10.1093/auk/100.2.335 ◽

1983 ◽

Vol 100 (2) ◽

pp. 335-343 ◽

Cited By ~ 11

Author(s):

M. Robert McLandress

Keyword(s):

Nearest Neighbor ◽

Average Distance ◽

Habitat Preferences ◽

Nearest Neighbors ◽

Nest Density ◽

Snow Goose ◽

Snow Geese ◽

Lesser Snow Geese ◽

Average Size ◽

Island Habitats

Abstract I studied the nesting colony of Ross' Geese (Chen rossii) and Lesser Snow Geese (C. caerulescens caerulescens) at Karrak Lake in the central Arctic of Canada in the summer of 1976. Related studies indicated that this colony had grown from 18,000 birds in 1966-1968 to 54,500 birds in 1976. In 1976, geese nested on islands that were used in the late 1960's and on an island and mainland sites that were previously unoccupied. Average nest density in 1976 was three-fold greater than in the late 1960's. Consequently, the average distance to nearest neighbors of Ross' Geese in 1976 was half the average distance determined 10 yr earlier. The mean clutch size of Ross' Geese was greater in island habitats where nest densities were high than in less populated island or mainland habitats. The average size of Snow Goose clutches did not differ significantly among island habitats but was larger at island than at mainland sites. Large clutches were most likely attributable to older and/or earlier nesting females. Habitat preferences apparently differed between species. Small clutches presumably indicated that young geese nested in areas where nest densities were low. The establishment of mainland nesting at Karrak Lake probably began with young Snow Geese using peripheral areas of the colony. Young Ross' Geese nested in sparsely populated habitats on islands to a greater extent than did Snow Geese. Ross' Geese also nested on the mainland but in lower densities than Ross' Geese nesting in similar island habitats. Successful nests with the larger clutches had closer conspecific neighbors than did successful nests with smaller clutches. The species composition of nearest neighbors changed significantly with distance from Snow Goose nests but not Ross' Goose nests. Nesting success was not affected by the species of nearest neighbor, however. Because they have complementary antipredator adaptations, Ross' and Snow geese may benefit by nesting together.

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Ecological and Physiological Factors Affecting Brood Patch Area and Prolactin Levels in Arctic-Nesting Geese

The Auk ◽

10.1093/auk/123.2.405 ◽

2006 ◽

Vol 123 (2) ◽

pp. 405-418 ◽

Cited By ~ 3

Author(s):

Jón Einar Jónsson ◽

Alan D. Afton ◽

Ray T. Alisauskas ◽

Cynthia K. Bluhm ◽

Mohamed E. El Halawani

Keyword(s):

Body Condition ◽

The Body ◽

Nest Size ◽

Patch Area ◽

Physiological Factors ◽

Factors Affecting ◽

Chen Caerulescens ◽

Brood Patch ◽

Snow Geese ◽

Ross's Geese

AbstractWe investigated effects of ecological and physiological factors on brood patch area and prolactin levels in free-ranging Lesser Snow Geese (Chen caerulescens caerulescens; hereafter “Snow Geese”) and Ross's Geese (C. rossii). On the basis of the body-size hypothesis, we predicted that the relationships between prolactin levels, brood patch area, and body condition would be stronger in Ross's Geese than in the larger Snow Geese. We found that brood patch area was positively related to clutch volume and inversely related to prolactin levels in Ross's Geese, but not in Snow Geese. Nest size, nest habitat, and first egg date did not affect brood patch area in either species. Prolactin levels increased as incubation progressed in female Snow Geese, but this relationship was not significant in Ross's Geese. Prolactin levels and body condition (as indexed by size-adjusted body mass) were inversely related in Ross's Geese, but not in Snow Geese. Our findings are consistent with the prediction that relationships between prolactin levels, brood patch area, and body condition are relatively stronger in Ross's Geese, because they mobilize endogenous reserves at faster rates than Snow Geese.Factores Ecológicos y Fisiológicos que Afectan el Área del Parche de Incubación y los Niveles de Prolactina en Gansos Nidificantes del Ártico

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