Randomization allowed calculation of confidence intervals for the population estimate, which previous censuses did not. CBC totals also show a slight but statistically significant increase over the past two decades of about one bird per count per decade, though this trend might have levelled off in the past decade (Figure 3). COSEWIC Secretariatc/o Canadian Wildlife ServiceEnvironment CanadaOttawa, ONK1A 0H3, Tel. Construction of any structures on Sable Island could potentially destroy sparrow habitat, both directly and by increasing the chance of erosion well beyond project footprints, but such activities are under rigorous permitting regulations. Nonetheless, the methods used (analysis of the mtDNA control region) were based on a small portion of the genome and are an indirect and perhaps weak test of reproductive isolation (Remsen 2005), especially considering the distinctiveness of Ipswich sparrows in other respects (Zink 2006). Raptors are presumably the main predators during migration and in winter (Stobo and McLaren 1975). The Committee on the Status of Endangered Wildlife in Canada (COSEWIC) assesses the national status of wild species, subspecies, varieties, or other designatable units that are considered to be at risk in Canada. 2005). Similarly, in San Diego in March 2009 I found that the quickest and easiest way to distinguish the endangered local resident Belding’s Savannah Sparrows from wintering Savannah Sparrows of northern populations was by behavior. Historically, the population survived numerous cats and foxes on the island for many years (Elliot 1968). © Her Majesty the Queen in Right of Canada, represented by the Minister of the Environment, 2006. ** Formerly described as “Not In Any Category”, or “No Designation Required.”*** Formerly described as “Indeterminate” from 1994 to 1999 or “ISIBD” (insufficient scientific information on which to base a designation) prior to 1994. McCann, S.B. The island is also a globally Important Bird Area, which again does not offer additional protection, but does formally recognize the island’s significance, in part because it holds the entire breeding range of the sparrow. Intensive studies in the late 1960s and 1970s (Stobo and McLaren 1975; Ross 1979, 1980a,b, 1981) yielded a thorough understanding of the bird’s biology, especially its ecology and demographics. Ph.D. dissertation, Dalhousie University, Halifax, Nova Scotia. Growth of nestling Ipswich Sparrows in relation to season, habitat, brood size, and parental age. Moreover, because Sable Island is a low–lying sand island, the entire island is vulnerable to the rises in sea–level that are projected to occur as a result of climate change. The fluctuation is thought to have been caused by particularly harsh winters (McLaren 1979). Également disponible en français sous le titre, « Plan de gestion du Bruant des prés de la sous-espèce princeps (Passerculus sandwichensis princeps) au Canada ». This management plan will clearly benefit the environment by promoting the conservation of the Ipswich Sparrows. Population, behavioural and grazing ecology of the horses of Sable Island. Rising, S. Mockford, A.G. Horn, J.M. Thus in the analyses below, search effort is taken into account by dividing the total number of birds by the number of count circles in which Ipswich sparrows were reported for each year (dividing by the number of participants in those counts yielded similar results, but in less readily interpretable units). November 2008. Hence, based upon summer counts, the breeding population nearly doubled during the 10–year period from 1995 to 2006. Temple, M. 1996. Rising. Mean number of Ipswich sparrows seen on the wintering grounds, based on Christmas Bird Count count circles that reported them, NatureServe Explorer: An online encyclopedia of life [web application]. 1975. 1979. The plan sets goals and objectives, identifies threats, and indicates the main areas of activities to be undertaken to address those threats. Environment Canada has reviewed and accepts this document as its management plan for the Savannah Sparrow, princeps subspecies, as required under the Species at Risk Act. Further evidence of the rarity of interbreeding comes from the Maritime Breeding Bird Atlas (Erskine 1992; MBBA 2008). McLaren, Ian. The author especially thanks Andrew Boyne of the Canadian Wildlife Service for the opportunity to prepare this report and for guidance throughout its preparation.