Foreword by W.A. Montévecchi
It is widely accepted that wisdom is nurtured by experience and age. Yet as our knowledge increases, so does our appreciation of the uncertainties in which that knowledge is embedded. This is especially evident in our growing understanding of the environment and of the nonhuman creatures that share it with us. In this respect, environmental wisdom is tempered with an appreciation of the interplay between our knowledge and our ignorance. The more we learn, the less simple and the less certain the answers become. Through immersion in long-term studies of Thickbilled Murres in the Canadian Arctic as the major part of his life's work, Tony Gaston has learned these lessons well. The investigations published here exemplify the type of research that is needed to improve our understanding of marine ecosystems and of their truly incredible inhabitants. As Leslie Tuck (1961) foretold a couple of decades before Tony began his Arctic studies with David Nettleship (Gaston and Nettleship 1981), Thick-billed Murres are vital manifestations of the Arctic ecosystems in which they live, mate, rear offspring, and die, as generational waves wash over one another through the evolutionary tides of environmental change.
The hunt of Thick-billed Murres in Newfoundland and Labrador is considered to represent a major source of adult mortality. The first contribution in this publication details an investigation to assess whether seasonal and bag limits imposed in 1993 to reduce winter hunt harvests in Newfoundland by 50% had measurable effects on the breeding population of Thick-billed Murres on Coats Island, Nunavut. No effect was detected in the survival of breeding adults, which remained relatively steady at about 90% per annum. Band recoveries by hunters of first-winter birds in Newfoundland exhibited no significant trends through the 1980s and 1990s, whereas band recoveries from murres 2 years of age and older, especially breeding-age birds, declined sharply after 1990. These findings suggested that breeding-age Thick-billed Murres changed their wintering distributions in Newfoundland waters, making them less vulnerable to hunters. This timing interestingly coincided with a major regime shift (Steele 1998) in the Northwest Atlantic. During the 1990s, primary forage and pelagic fishes exhibited significant distributional changes, some of the initial indications of which came from studies of the feeding ecology of seabirds that breed in Newfoundland (Montevecchi and Myers 1992, 1996) and Labrador (Bryant et al. 1999). Thick-billed Murres, it appears, integrate a dynamic interplay among High and Low Arctic ecosystems and the interactive influences of human hunters.
The second contribution in this publication reports on the results of 25 years of effort in monitoring populations of Thick-billed Murres in the eastern Canadian Arctic. The number of colonies consistently monitored is not as extensive as one (including Tony Gaston) might hope. However, very considerable effort has been involved, and Gaston compiles all of the systematic information that is available. These archival data and especially the photographic information provided in Appendix 1 will undoubtedly be invaluable to researchers in the future who, like Tuck and Gaston before them, will revisit questions of long-term population dynamics and environmental change. Murre populations at Coats and Prince Leopold islands appear to have decreased between 1989 and 1991, whereas those at Digges Island likely declined between 1985 and 1990. All colonies appear relatively stable at present, and the counts go on. Consistent population trends among distant Arctic colonies again suggest that circumstances on wintering grounds in the Low Arctic waters of the Labrador Sea have major influences on breeding populations in the High Arctic. Clearly, to understand the population dynamics of Thick-billed Murres, it is essential to unravel the environmental influences occurring in their habitats in High and Low Arctic ocean regimes.
From a professional perspective, it is encouraging to see this research continuing. It is also encouraging to see it published in the Canadian Wildlife Service Occasional Papers as the fifth contribution of the "Studies of highlatitude seabirds" series that Tony and I initiated at an international seabird workshop at Memorial University of Newfoundland in 1989 (Montevecchi and Gaston 1991). From both a professional and a personal view, it's good to see Tony Gaston doing what he does best.
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