CBC data show roughly cyclical fluctuations (Figure 3), which might correlate with the North Atlantic Oscillation, with higher counts following milder summers on Sable Island (I.A. As well, there is no evidence that grazing or trampling by horses destroys sparrow habitat on Sable Island. Freedman, B. In the only genetic study of differentiation between Ipswich sparrows and other Savannah Sparrows, Ipswich sparrows were not reciprocally monophyletic from “typical” Savannah Sparrows collected from sites scattered widely across North America, from Newfoundland to Alaska (Zink et al. In particular, a temporary population crash of about 50% appears to have occurred in the late 1970s, probably because of harsh weather during migration and wintering. Interestingly, all five Ipswich sparrows that have been found on the mainland during the breeding season were female (based on lack of singing and other territorial behaviours), which weakly suggests a reproductive isolating mechanism related to mate choice (Stobo and McLaren 1975) or perhaps sex differences in dispersal patterns. These Savannah Sparrows were obviously not tied to a territory, and it seemed safe to assume that they were migrants bound for breeding areas farther north. In The Birds of North America, No. McLaren, I.A. A stratified random, rather than random, selection of transects was used because the island’s habitats change across its length, roughly from sparse marram to dense marram to heath as one moves towards the island’s centre (Smith et al. Invaluable unpublished information was provided by Marty Leonard, Zoe Lucas, Ian McLaren, Steve Mockford, Dave Patriquin, Jim Rising, and Bob Zink. Thanks also to Canadian Wildlife Service, Habitat Conservation Section for their advice and Canadian Wildlife Service, Recovery Section for their advice and efforts in preparing this document for posting. The next census, in 1995, yielded 3400 individuals (Horn 1999). State Coastal Program Effectiveness in Protecting Natural Beaches, Dunes, Bluffs, and Rocky Shores. Wheelwright, N.T. Once I was able to sort the birds by behavior, the differences in coloration stood out. On June 5, 2003, the Species at Risk Act (SARA) was proclaimed. Ph.D. candidate, Department of Biology, Queens University, Kingston, Ontario. New documents will be added regularly as species get listed and as plans are updated. For many species, the ultimate aim of the management plan will be to alleviate human threats and remove the species from the List of Wildlife Species at Risk. The potential for the plan to inadvertently lead to adverse effects on other species was considered. and A.G. Horn. Unpublished report prepared for the Canadian Wildlife Service, Atlantic Region, Dartmouth, NS. During post–doctoral work at University of Cambridge, Queens University, and Agriculture Canada, he studied various aspects of parent–offspring interactions and acoustic communication in birds, work he continues as a Research Adjunct at Dalhousie University. SARA establishes COSEWIC as an advisory body ensuring that species will continue to be assessed under a rigorous and independent scientific process. In early March, the Belding’s were territorial, while wintering Savannah Sparrows in the same area were in roving flocks, acting like wintering birds. Predation was mentioned in earlier status reports as a potential threat, but, while predation rates of Ipswich sparrows vary across years, they are typically low for a ground–nesting passerine. vi + 21 pp. Également disponible en français sous le titre, « Plan de gestion du Bruant des prés de la sous-espèce princeps (Passerculus sandwichensis princeps) au Canada ». NatureServe. Since then, an analysis of CBC data suggests that the centre of abundance of wintering birds appears to have shifted about 160 km south, but changes in neither the northern limit, southern limit, nor centre of occurrence were statistically significant (Dale 2007). Temple, M. 2000. and I.A. Overwinter survival appears to be the most important limiting factor on the population. Overall, both summer censuses and CBC data suggest that the population increased in the 1990s, but may have levelled off in the past decade. Until 1973, the American Ornithologists’ Union (AOU) considered the Ipswich sparrow to be a distinct species, based on its morphology, plumage, and restricted, isolated breeding range. thesis, Dalhousie University, Halifax, Nova Scotia. This management plan has been prepared in cooperation with the jurisdictions responsible for Savannah Sparrow, princeps subspecies. 2008. Committee on the Status of Endangered Wildlife in Canada. Thus, trends in wintering habitat can only be inferred from more general data on overall trends in dune beach habitat, much of which has been destroyed historically by dense human settlement along the eastern seaboard of the US. Ottawa. 1992. 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. About 200–350 horses roam freely on Sable Island, undoubtedly affecting sparrow habitat. 1979. Pattern, process, and rigor meet classification. Thanks to Ian McLaren for permission to use the cover photograph of an Ipswich sparrow. Status re–examined and confirmed in May 2000 and in November 2009. Ipswich sparrows eat a wide range of seeds and insects, primarily the seeds of Marram Grass in the summer and Sea Oats (Uniola paniculata) in the winter (Stobo and McLaren 1971, 1975). Though not a true Canadian endemic species because it winters in the U.S., the Ipswich sparrow is perhaps Canada’s best–known, range–restricted breeding songbird. Mean number of Ipswich sparrows seen on the wintering grounds, based on Christmas Bird Count count circles that reported them. The Committee meets to consider status reports on candidate species.


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