The Canadian field-naturalist. Ottawa,Ottawa Field-Naturalists' Club.

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1 The Canadian field-naturalist. Ottawa,Ottawa Field-Naturalists' Club. v.114 (2000): Page(s): Page 692, Page 693 Contributed by: Harvard University, Museum of Comparative Zoology, Ernst Mayr Library Sponsored by: Harvard University, Museum of Comparative Zoology, Ernst Mayr Library Generated 24 May :54 PM

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5 The following text is generated from uncorrected OCR. [Begin Page: Page 692] 692 The Canadian Field-Naturalist Vol. 114 Recent Reports of Grizzly Bears, Ursus arctos, in Northern Manitoba Douglas Clark Kluane National Park, P.O. Box 5495, Haines Junction, Yukon, YOB ILO, Canada Present address: Wapusk National Park, P.O. Box 127, Churchill, Manitoba, ROB OEO Canada Clark, Douglas Recent reports of Grizzly Bears, Ursus arctos, in northern Manitoba. Canadian Field- Naturalist 114(4): I evaluate three reports of sightings of Grizzly Bears (Ursus arctos) from 1990 to 1998 in northeastern Manitoba. These observations indicate that Grizzly Bears may be extending their range to the southeast into Manitoba, a province from which they were thought to have been extirpated. Key Words: Grizzly Bear, Ursus arctos, Wapusk National Park, Hudson Bay Lowlands, Manitoba. The Grizzly Bear {Ursus arctos) has been consid-

6 ered extirpated from Manitoba, though they formerly ranged throughout the prairies in the southwest quarter of the province (Banci 1991*). The last unconfirmed sighting was made in the Duck Mountains in 1923 (Sutton 1967). I summarize and evaluate recent sightings of Grizzly Bears in northeastern Manitoba. On 27 July 1990, A. Didiuk, Canadian Wildlife Service, observed and photographed a Grizzly Bear from a fixed-wing aircraft approximately 1 km inland from the Hudson Bay coast between Hubbart Point and Nunalla (Figure 1), at 59 34' N, 94 52' W (Roberts 1997*). Didiuk was familiar with the diagnostic features of bears, and confirmed the presence of the shoulder hump and a concave facial profile typical of Grizzly Bears. A Grizzly Bear was apparently seen in that area that year by local hunters, and an experienced local trapper saw its tracks (J. Batstone, personal communication). On 15 June 1996, D. Humburg, Missouri Department of Conservation, reported sighting and photographing a Grizzly Bear from a fixed-wing aircraft 6.5 km from the coast, near Thompson Point, in Wapusk National Park (Figure 1) at 58 14' N, 93 04' W (Roberts 1997*). The photographs show a shoulder hump and concave facial profile. Humburg was also familiar with Grizzly Bears, having seen

7 them before in other areas. On 5 June 1998, I observed a Grizzly Bear from a helicopter moving along a coastal beach ridge near Thompson Point in Wapusk National Park (Figure 1 ) at 58 20' N, 93 02' W. The diagnostic features of the shoulder hump and concave facial profile were clearly visible. The bear appeared to be mature and in Hudson Bay Figure 1. Map of northeastern Manitoba showing locations of Grizzly Bear observations: (a) 27 July 1990, (b) 15 June 1996, (c) 5 June Shaded area indicates Wapusk National Park. Inset map shows the location of the park within Manitoba. [Begin Page: Page 693] 2000 Notes 693 good condition. Tracks found in mud in the vicinity the next day were examined and imprints of the characteristically long claws were cleariy visible; much longer than the claw imprints of a Polar Bear {Ursus maritimus) or Black Bear {Ursus americanus), which

8 also inhabit the area. The toe imprints in these tracks were joined, and did not arc, both of which characteristics are indicative of Grizzly Bear, rather than Black Bear tracks (Herrero 1985). The bear was not seen again despite an intensive search of the area on subsequent days. These three reports meet the highest rating in the criteria developed by Almack (1986*) for evaluating reports of Grizzly Bears. All sightings were made by experienced observers and photographs were taken. At least two criteria distinguishing grizzlies from Black Bears were noted in each case; a prominent shoulder hump, concave facial profile or long claws. Black Bears in Manitoba can exhibit variable coat colour, including brown and blonde, though such colour phases are generally rare in the northern part of the province (W. Roberts, personal communication), so colour cannot be considered an identifying criterion. All of these sightings were made in the Hudson Bay Lowlands Ecozone, outside any of the ecozones which Banci (1991*) identified were important to Grizzly Bears. It is unclear whether or not the habitat is of sufficiently high quality to support Grizzly Bears year-round in the Hudson Bay Lowlands. South of the Seal River, midway between the obser-

9 vation sites, there are no Arctic Ground Squirrels (Spermophilus parryii) which are generally felt to be important to Grizzly Bears in other Arctic areas (Nagy et al. 1983). Further, the Wapusk National Park area has very low berry productivity, and other plants which are considered to have high value for Grizzly Bears elsewhere in their range, such as Sweet Vetch {Hedysarum sp.) are sparse (Clark 1996). The tracks observed in 1998 proceeded in a straight line towards a Canada Goose (Branta canadensis) nest containing eggs, then veered away, possibly because of the helicopter. In spring, the area where this and the 1996 observation were made contains a high number of nesting Canada Geese and Lesser Snow Geese {Chen caerulescens). Grizzlies are known to eat goose eggs, goslings and moulting flightless geese. Also, the Cape Churchill Caribou {Rangifer tarandus) herd calves in the area, providing another potential food source. Since there is no known source population of Grizzly Bears to the south or west of these sightings, which is bordered to the east by Hudson Bay, it is most hkely that the bear or bears observed had travelled south from resident populations in the Northwest Territories. Barren-Ground Grizzly Bears have large home ranges and move long distances, particularly in the spring and summer. P. McLoughlin

10 (personal communication), found that the mean annual range of adult male Grizzly Bears in the central Northwest Territories is 6685 km^, and that they may move up to 12 km per day in the spring. Taylor (1995) observed an adult male Grizzly Bear on sea ice over 500 km from any known source population. Such ranges and movements are consistent with the distance between known Grizzly Bear populations and the location of the recent observations in Manitoba. Elders of the York Factory First Nation indicated that they had no knowledge of Grizzly Bears in the area (Flora Beardy, personal communication), which they have inhabited for over 300 years. However, both they and elders from the Fox Lake First Nation have Cree names for the Grizzly Bear and distinguish it from Black and Polar bears, suggesting an awareness of this species. Preble (1902) mentioned that Grizzly Bears were not known from the area around Churchill; only from the barren lands to the northwest, and they were, at most, rare. It is not clear if these three sightings indicate a possible trend toward an extension of their range from the Northwest Territories into northeastern Manitoba. Grizzly Bears were thought to have increased their range southeastward in the mainland Northwest Territories during the 20th century (Banfield 1959;

11 Harington et al. 1962). However since the mid-1960s there have been many surveys in the area where these sightings were made and it is likely that if significant numbers exist they would have been observed. Conclusions about the population status of Grizzly Bears in Manitoba cannot be drawn from these recent observations. However it is important to document these observations since there have been so few records of Grizzly Bears in northern Manitoba, and it is possible the population to the north may be in the process of extending its range. Acknowledgments I thank Wayde Roberts, Manitoba Department of Conservation, Churchill; Gary Ertel, Canadian Coast Guard, Thunder Bay; Phil McLoughlin, University of Saskatchewan, Saskatoon; and Wapusk National Park staff and Management Board members for thenassistance and support. Ian Stirling, Canadian Wildlife Service, Edmonton, provided constructive criticism of the manuscript. Documents Cited (marked * in text citations) Almack, J North Cascades Grizzly Bear Project, Annual Report. Washington Department of Wildlife, Olympia, Washington. 71 pages.

12 Banci, V The status of the Grizzly Bear in Canada in COSEWIC Status Report. 171 pages. Roberts, W Grizzly Bear sightings. Unpublished Report, Manitoba Department of Natural Resources, Churchill, Manitoba. 4 pages.