736 Abstract—Aerial surveys to estimate Numbers and distribution of beluga whales, the numbers of beluga whales, Delphi- napterus leucas, were fl own in James Delphinapterus leucas, in James Bay, Bay, eastern Hudson Bay, and Ungava Bay in Canada in the summer of 1993 eastern Hudson Bay, and Ungava Bay on transects systematically spaced 5 or in Canada during the summer of 1993 10 nmi apart. In James Bay and east- ern Hudson Bay line-transect methods were used. In Ungava Bay strip tran- Michael C. S. Kingsley sects were used, and off-transect sight- Canadian Department of Fisheries and Oceans ings were also recorded. Beluga whales Maurice Lamontagne Institute were also counted on coastal fl ights in 850, Route de la mer eastern Hudson Bay and Ungava Bay. Mont-Joli, P.Q. G5H 3Z4 James Bay and eastern Hudson Bay Present address: Pinngortitaleriffi k—Greenland Institute of Natural Resources were surveyed in August; Ungava Bay P.O. Box 570 in July and again in August. Watches DK-3900 Nuuk were kept from land at estuaries in Greenland eastern Hudson Bay in 1993 and in E-mail address:[email protected] Ungava Bay in 1992 and 1993. The estimates of detectable beluga whales (uncorrected for diving and observer errors) were 3141 (SE=787) in James Bay and 1014 (SE=421) in eastern Hudson Bay. A further 115–148 beluga whales were seen near the coast James, Hudson and Ungava bays are a means of procuring food, as a tra- of eastern Hudson Bay during the summering areas for stocks of beluga dition helping to defi ne their culture, coastal survey, but mostly away from whales (Delphinapterus leucas) (Ser- and as a recreation. Maintaining beluga traditionally used estuaries. The esti- geant and Brodie, 1975; Finley et al., whale hunting, and stocks adequate to mate for James Bay was nearly three 1982; Smith and Hammill, 1986; Rich- support it, are important objectives for times the previous estimate, made in 1985, possibly because ice cover in ard et al., 1990). There are several appar- the Inuits. Commercial hunting in the James Bay was much lower in 1993 ently separate summer groups, which 19th century severely reduced numbers than in the 1985 survey. The 1993 esti- include a summer group of ~23,000 of beluga whales on the eastern coast mate for eastern Hudson Bay was close individuals in western Hudson Bay, a of Hudson Bay and in Ungava Bay and to that for 1985. No beluga whales were group of 1500 individuals in the eastern they have not yet recovered (Reeves and seen during aerial transects in Ungava Hudson Bay arc, and a few individuals Mitchell, 1987a; 1987b; 1989). These Bay, but they were seen off-transect in Ungava Bay (Smith and Hammill, stocks were listed as “threatened” and and on coastal fl ights, mostly in or near 1986; Richard et al., 1990). Beluga “endangered,” respectively, by the Com- the Whale River estuary in southern whales, probably composing other sepa- mittee on the Status of Endangered Ungava Bay. The largest group sighted rate groups, also summer in southern Wildlife in Canada (Campbell, 1993), and the greatest number seen in any day consisted of 20 individuals, a mini- Hudson Bay (Richard, 1993) and James and exploitation still occurs (DFO, mum size for the summer population in Bay (Smith and Hammill, 1986). 1996; NAMMCO, 1999) A low reproduc- Ungava Bay. An upper 90% confi dence A land claim agreement was signed tive rate limits the species’s potential limit for summer numbers is impre- between the Inuit of the central and for increase (Sergeant, 1981; Kingsley, cisely estimated at 150. eastern Canadian Arctic and the Gov- 1989); therefore careful monitoring and Neither the coastal surveys nor the ernment of Canada in 1990 (Anony- management of stocks are appropriate. land-based observations in Hudson Bay mous, 1993). In eastern Hudson Bay, Population management requires per- and Ungava Bay indicated the presence this land agreement defi ned a marine iodic evaluations of stock size, as a of large, dense herds that might have area around the Belcher Islands (the basis for setting harvest levels and been ineffi ciently sampled by transect “Nunavut Settlement Area”) for the use for estimating the effect of harvest survey. of the benefi ciaries of that agreement on the population trend. Beluga whale (Figs. 1 and 2). It also defi ned an area stocks are evaluated by aerial survey in north and east of the settlement area their summering areas. The previous, (the “Equal Use and Occupancy Area”) and fi rst, offshore aerial survey of to be shared by the Inuit of Nunavut James Bay, eastern Hudson Bay, and and those of northern Quebec. Other Ungava Bay was fl own in summer 1985 provisions of the agreement, and of (Smith and Hammill, 1986), and the the earlier James Bay and Northern development in the early 1990s of a Quebec Agreement, assured the aborig- beluga whale management plan for inal people of a right to hunt beluga northern Quebec rendered it timely to whales in these waters. update information on the population. Manuscript accepted 28 March 2000. The hunting of beluga whales is This article reports the results of Fish. Bull. 98:736–747 (2000). valued by Inuit in northern Canada as aerial surveys fl own in summer 1993. A Kingsley: Number and distribution of Delphinapterus leucas, in James, Hudson, and Ungava Bays, Canada 737 Figure 1 Map of northeastern Canada, showing the locations of the 1993 beluga whale aerial surveys in James Bay, eastern Hudson Bay, and Ungava Bay. systematic transect survey was fl own over offshore areas used in 1985 (Smith and Hammill, 1986) (Fig. 2). They were of James Bay, eastern Hudson Bay, and Ungava Bay (Figs. on exact 10′ lines of latitude (i.e. 18.52 km apart) from the 1–3). However, summering beluga whales often form dense southern end of James Bay at 51°10′N as far as 58°50′N coastal concentrations, which are ineffi ciently estimated near Inukjuak, and additional lines were interpolated at by sample survey. Therefore, coastal surveys were also 5′ (9.26-km) intervals between 55°35′N and 57°35′N, i.e. in fl own in eastern Hudson Bay and Ungava Bay to check the central part of the Hudson Bay arc. whether large numbers in concentration areas might have The survey of Ungava Bay was also based on systematic caused serious errors in the results of sample surveys. To designs (Fig. 3). South of 59°30′N, the initial design had the same end, watches were kept over known estuarine north–south transects on every 15th minute of longitude, concentration areas from vantage points on land in 1992 a spacing approximately equal to 7.5 minutes of latitude and 1993. (13.9 km). North of this line the transects lay east–west on every tenth minute of latitude, i.e. 18.52 km apart. Earlier surveys of Ungava Bay had detected few beluga Methods whales (Finley, 1982; Smith and Hammill, 1986). Inuk hunters had suggested that fl ying at different times in Beluga whales concentrate in and around the mouths of the summer might produce different results; therefore the rivers in summer, and this habit largely defi nes accepted Ungava Bay survey was fl own twice: in mid-July and in stocks (Brown Gladden et al., 1997). Therefore aerial surveys late August. In both surveys, sections of the coastline were for stock assessment are normally carried out in summer in followed and surveyed when ferrying to and from transect these areas. The survey area for this study comprised James blocks, so that the coastline, particularly near the logistic Bay, the eastern Hudson Bay arc north to 59°N and as far base at Kuujjuak, was repeatedly covered. west as 80°20′W, and Ungava Bay. This area was similar to The transect survey of James Bay and eastern Hudson that covered by the previous aerial survey of these stocks in Bay was fl own in a Cessna 337 aircraft, at 1500 feet (457 m) 1985 (Smith and Hammill, 1986). Beluga whales are uncom- above sea level at about 130 knots, (67 m/s), and navigated mon in summer along the northern part of the eastern coast by GPS. The aircraft was equipped with fl at windows. of Hudson Bay and the southern coast of Hudson Strait Observers sat in the two seats behind the pilot. Line- (Finley et al., 1982; Smith and Hammill, 1986); therefore the transect survey methods were used, in which all sightings survey did not include these areas. were recorded with their distance from the transect line, The transects in James Bay and eastern Hudson Bay and a sighting curve was subsequently calculated to correct were systematically spaced east–west lines similar to those for the decreasing detectability of targets with distance. 738 Fishery Bulletin 98(4) The angle of view from the horizontal was measured side of the chains of islands close to the coast, and the with Suunto inclinometers. Records were made with time- plane made a detour to survey Richmond Gulf. It fl ew as coding tape recorders and were transcribed daily. Ground far south as the Vauquelin River before returning to end speeds were calculated from the elapsed time on the at Kuujjuaraapik (Fig. 2). transect and sighting positions were interpolated along The Ungava Bay surveys used strip-transect methods. transects. The state of the sea was assessed and recorded A “Twin Otter” aircraft was fl own at an altitude of 1500 by using the Beaufort Scale of wind force; survey plans feet (457 m).