Foreword by J. Stephen Wendt
Throughout Canada, biologists have been working to improve our understanding of the status and trends of Canada Geese (Branta canadensis). There is no part of the country that is not touched by this species. Yet, despite its apparent commonness and widespread distribution, the knowledge of some types is imperfect. Some Canada Goose populations, such as those breeding in the Arctic, are doing reasonably well (this publication: Hines et al.; Dickson), as are temperate-breeding Canada Geese (this publication: Nieman et al.; Dennis et al.; Smith). In contrast, some of those breeding in boreal or subarctic regions of Canada have experienced recent declines, for reasons that are only partly understood (this publication: Leafloor et al.; Breton et al.). The Waterfowl Committee of the Canadian Wildlife Service resolved in 1994 to produce this publication to report on the great advances in understanding Canada Goose populations that have occurred in recent years. Some forward strides resulted from concerted large-scale efforts such as a range-wide neck-banding program aiming to update our knowledge of the distributions of Canada Geese and White-fronted Geese breeding throughout the Arctic. Much new information resulted from this extensive study, supported by concerned wildlife agencies throughout Canada and the United States (this publication: Hines et al.; Dickson). Other progress was possible because of scientific studies in support of environmental assessments for developments like reservoir creation (Hughes et al., this publication) and activities of the wildlife habitat mitigation program of the Department of National Defence (Bateman, this publication). Although waterfowl managers have relied in the past on winter surveys to track population trends for these management units of Canada Geese, the distribution of different groups of birds on wintering areas is becoming less discrete and predictable. The growth explosion of "giant" (or "resident" or "temperate-breeding") Canada Geese (Dennis et al., this publication), along with changes in winter distributions of migrant geese, means that winter counts are less useful for measuring trends in each Canada Goose population. In some cases, reliance on winter counts has masked serious declines in migrant populations (e.g., Atlantic Population, Southern James Bay Population), delaying and complicating the implementation of conservation plans. Whenever possible, we must adopt a "breeding grounds approach," taking measures of status and population health from the nesting areas. This fundamental change in philosophy is reflected in every paper in this publication. To say that we wish to change perspective to enable management of geese based on breeding ground distributions reflects what we believe should be our foremost goal. That is, we should strive to conserve species throughout their ranges, in this case, by conserving the diversity of Canada Geese from Alaska to Newfoundland, and south to Mexico. We do not mean to suggest that by focusing on the breeding grounds we will eliminate all difficulties associated with estimating population status. For example, spring surveys of every population of B.C. interior (included in the Mississippi Valley, Eastern Prairie, Southern James Bay, and Atlantic populations; see Figs. 5-8 in Dickson, this publication) are confounded to a lesser or greater degree every year by the presence of other Canada Geese arriving from southern breeding areas to spend the moulting period farther north. The degree of confusion is related to the phenology of the spring: early springs in the south may lead to earlier appearances of moult-migrants in the north. If spring is average, or even later than average, on the northern breeding areas, the moult-migrants may arrive before the northern geese are well into the incubation period. In such cases surveys of breeding birds may well include nonbreeding individuals from other stocks. In 1998, however, spring arrived early throughout the breeding range of B.C. interior, and surveys could be conducted before the arrival of moult-migrants. Even so, the surveys that year were compromised by another effect of the extremely early spring: the geese nested so much earlier than usual that survey crews could not arrive at the optimal time. Such difficulties are discussed by Leafloor and Abraham, Humburg et al., Leafloor et al., and Breton et al. in later chapters. It is important that information and results from studies be made available as quickly as possible for use by management agencies. For some populations, estimates of breeding population size and production rates are used immediately to produce estimates of allowable harvests, and we must continue to evaluate survey methodologies and their predictions (Leafloor and Abraham, this publication). Not only is the information immediately useful, it also becomes more difficult to work with as time passes. An example is the exceptional job by Tony Erskine to accumulate and make sense of 40 years of information. We hope that this publication will also serve the purpose of comprehensive and timely presentation of information.
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