Winter distribution and pre-breeding survival of the thick-billed murre, Uria lomvia, from the northwestern Atlantic. Implications for management of the Newfoundland turr hunt.

• Main Author: Donaldson, Gary Michael.
• Other Authors: Gaston, A. J.
• Format: Thesis
• Language: unknown
• Published: University of Ottawa (Canada) 1995
• Subjects: Biology; Ecology; Coats Island; Coburg Island; Digges; Greenland; Coburg island; Newfoundland; thick-billed murre; Uria lomvia; uria
• Online Access: http://hdl.handle.net/10393/10082; https://doi.org/10.20381/ruor-8119

New legislation which entrenches regulation of the turr hunt in Newfoundland into the Migratory Birds Convention Act, will require good knowledge of thick-billed murre (Uria lomvia) population biology for proper implementation. The impact of hunting on the population is determined by factors such as total bag, season length and timing, and the age of birds killed. These in turn depend on the temporal and spatial distribution of murres of different ages and from different colonies. Birds in their first winter were recovered in greater numbers than birds from older age categories and were usually recovered earlier in the season. Recovery rates of first winter and second winter birds from Digges Island were significantly lower than those for birds of the same age from the adjacent colony on Coats Island suggesting different spatial distributions of the young birds from the two colonies. Differences in the overwintering areas for adults from Coburg Island and Cape Hay, again located closely together, differed significantly with Coburg adults recovered in greater numbers in Newfoundland while Cape Hay adults were recovered most often in Western Greenland. Using recoveries of birds banded on Coats Island, annual survival from fledging to first year was estimated at 0.53 using the program SURVIV. Survival from second to third year was estimated at 0.83, from third to fourth year was 0.74, from fourth to fifth year was 0.86. The estimate from third to fourth year was considered to be an underestimate as a result of the high mobility of third year birds at the colony. Based on these survival probabilities, survival to breeding age, using the best estimates from band recoveries and resightings was estimated at 0.27. (Abstract shortened by UMI.)