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Three 4-month-old Wolf (Canis lupus) pups in the Superior National Forest of Minnesota died during August and September 1997, apparently from coccidiosis. This appears to be the first record of coccidiosis in Wolves.
Low sample size and high variation within populations reduce power of statistical tests. These aspects of statistical power appear to have affected an analysis comparing overwinter survival rates of non-orphan and orphan Caribou ( Rangifer tarandus ) calves by an earlier study for the Porcupine Caribou Herd. A re-evaluation of the data revealed that conclusions about a lack of significant difference in the overwinter survival rates between orphan and non-orphan calves were premature.
Coburg Island and neighbouring waters were recently designated a Canadian National Wildlife Area. The large seabird colony at Cambridge Point has been previously described, and is dominated by Thick-billed Murres (160 000 pairs). We found that a small offshore island, named Princess Charlotte Monument, also supported breeding populations of seven marine bird species; three of which did not breed at the main colony (i.e., Northern Fulmar, Common Eider, and Atlantic Puffin). This is the most northern confirmed breeding site for Atlantic Puffins in Canada. Puffins at both Coburg Island and northern Greenland nest in rock crevices, apparently because permafrost in soil prevents burrow nesting. We suggest that puffin populations in the high arctic may be limited by habitat, rather than prey availability.
Based on 418 radio-locations of a Minnesota Wolf pack, Wolves were found at significantly fewer locations per area in the outer 2 km of the territory than in the core. This finding supports an hypothesis that buffer zones exist between pack territories and may explain why prey survive longer there.
A significant relationship was found between Wolf (Canis lupus) breeding dates and latitudes between 12?? and 80??N, with Wolves breeding earlier at lower latitudes, probably because of differences in seasonality.
The Northern Mockingbird (Mimus polyglottos) is a common bird in the southern United States that has been expanding its breeding range into the northern United States and southern Canada. During the twentieth century, there were 128 reports of Northern Mockingbird occurrences in North Dakota, including 106 reports during the breeding season (15 April to 31 August) and 22 during the nonbreeding season (1 September to 14 April). The species has been largely absent from North Dakota from January through mid-April. Prior to the 1930s, there was only one record (1916) of the Northern Mockingbird in the state. Observations of Northern Mockingbirds in North Dakota increased markedly between the 1930s and 1990s. On average, there were 0.3 reports of mockingbirds per year in 1931-1940, 0.6 in 1941-1950, 1.1 in 1951-1960, 1.6 in 1961-1970, 2.4 in 1971-1980, 2.3 in 1981-1990, and 4.5 in 1991-2000. The species has been observed in North Dakota nearly annually since 1958. At least six reports during the twentieth century included evidence of nesting (nests or dependent young). Based on mockingbird records during the twentieth century, we designate the current status of the Northern Mockingbird in North Dakota as a rare spring migrant, rare summer visitant, casual nester, and a casual fall and winter visitant.
Based on 168 records of both verbal descriptors of White-tailed Deer (Odocoileus virginianus) femur-marrow fat and percentage of fat measured later, "gelatinous" served well to distinguish fat < 46% from higher percentages. "Waxy" distinguished fat > 56%.
We examined the spatial interactions of nine female White-tailed Deer (Odocoileus virginianus) in two deeryards (winter aggregations) in northeastern Minnesota during February-April 1999. Global positioning system (GPS) collars yielded seven pair-wise comparisons of deer that were located at the same time (???1 minute apart) and mat used overlapping areas. Deer traveled separately and did not associate with one another. Within overlapping areas, comparisons of distances between deer and distances between random locations indicated deer moved without regard to each other. Similarly, comparisons of observed and expected probabilities of deer using areas overlapping those of other deer also evinced that deer moved independently.
Dominance is one of the most pervasive and important behaviors among wolves in a pack, yet its significance in free-ranging packs has been little studied. Insights into a behavior can often be gained by examining unusual examples of it. In the High Arctic near Eureka, Nunavut, Canada, we videotaped and described an unusually prolonged and intensive behavioral bout between an adult male Gray Wolf ( Canis lupus ) and a male member of his pack, thought to be a maturing son. With tail raised, the adult approached a male pack mate about 50 m from us and pinned and straddled this packmate repeatedly over 6.5 minutes, longer than we had ever seen in over 50 years of studying wolves. We interpreted this behavior as an extreme example of an adult wolf harassing a maturing offspring, perhaps in prelude to the offspring?s dispersal.
American White Pelicans (Pelecanus erythrorhynchos) are colonial nesters, making them susceptible to site-specific mortality factors. One of the largest known breeding colonies is at Chase Lake National Wildlife Refuge in North Dakota. In 2004, this colony suffered total reproductive failure. In 2005, we collected abandoned eggs from this colony to test for environmental contaminants. Nine eggs were analyzed for 28 organochlorine pesticides, total polychlorinated biphenyls, and 26 inorganic elements. Based on concentrations in this sample of eggs and levels linked to reproductive problems in birds, adult pelicans in the Chase Lake breeding colony are not at known risk from any of the environmental contaminants we measured.
A two-year-old sibling Gray Wolf (Canis lupus) carefully captured an Arctic Hare (Lepus arcticus) leveret alive on Ellesmere Island, Nunavut, Canada, and delivered it alive to a pup 28–33 days old. This appears to be the first observation of a Gray Wolf delivering live prey to a pup.
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Histological ovarian analysis indicates summer spawning occurs in Myoxocephalus quadricornis (Fourhorn Sculpin) from Alaska. Previous studies have shown this species spawns during winter in the Baltic Sea; the data presented herein suggests that geographical variation may occur in the timing of spawning of this species.
Two Red Foxes (Vulpes fulva ) that invaded Shaiak Island before the 1976 nesting season had a marked impact on the nesting success of five of seven species of seabirds breeding on the island that year. Common Eiders ( Somateria mollissima ), Glaucous-winged Gulls ( Larus glaucescens ), and Common Murres ( Uria aalge ), that nest in areas accessible to foxes, did not raise any young to fledging. Double-crested Cormorants ( Phalacrocorax auritus ) were only slightly more successful; 13 (4.3%) of 300 pairs raised one or more young to fledging. Evidence suggested that 21 (35.6%) of 62 pairs of Tufted Puffins (Lunda cirrhata ) lost eggs or chicks to foxes, and foxes killed at least 13 (8.3%) of 156 adult puffins on ten sample plots. Conversely, Black-Legged Kittiwakes ( Rissa tridactyl a) and Pelagic Cormorants ( Phalacrocorax pelagicus ), which nested primarily on cliffs inaccessible to foxes, lost very few nests. There was no apparent change in general nest site selections by seabirds the following year, when foxes were no longer present. Any avoidance by birds of areas vulnerable to fox predation would probably be discernible only after several years of continuous predation.
The nesting biology of Pacific Loons, Gavia pacifica , was studied from 1973 to 1975 on the Yukon-Kuskokwim Delta, Alaska. Loons maintained territories on ponds throughout the pre-nesting period. Both adults incubated eggs and raised the young. Males incubated more than females during early incubation, and females more than males during late incubation. The female assumes much of the early brood rearing, with the male assisting more when food demands of young increase later in brood rearing.