. The Canadian field-naturalist. 132 The Canadian Field-Naturalist Vol. 101 (Eberhardt 1978), and sailed from the coast as far out as the 200 m depth contour (Figure 1). We made such transects along the coast (and back) between St. Anthony, Newfoundland (51°30'N, 55°28'W) and Nain, Labrador. The vessel left St. Anthony on 12 August 1982, and returned on 28 August 1982. One observer of a crew of four was on deck to keep watch at all times. With the onset of darkness, the boat was hove to or anchored in nearby coves. The survey was made under sail unless the ship's speed dropped below 2 knots, i
. The Canadian field-naturalist. 132 The Canadian Field-Naturalist Vol. 101 (Eberhardt 1978), and sailed from the coast as far out as the 200 m depth contour (Figure 1). We made such transects along the coast (and back) between St. Anthony, Newfoundland (51°30'N, 55°28'W) and Nain, Labrador. The vessel left St. Anthony on 12 August 1982, and returned on 28 August 1982. One observer of a crew of four was on deck to keep watch at all times. With the onset of darkness, the boat was hove to or anchored in nearby coves. The survey was made under sail unless the ship's speed dropped below 2 knots, in which case the engine was used. Results Strip census data Findrinny covered a total distance of 2517 km (1) off Labrador during the dolphin census. When we looked at the distribution of right angle distances between the transect line and sighting positions, it seemed that few dolphins were missed within km (d) of the transect line and this, therefore, was chosen as the effective strip width. We saw 130 dolphins (n) within km of the transect line. The area of the continental shelf off Labrador between 51°30'N, 55°28'W and 56°00'N, 61°45'W, which is less than 200 m deep (excluding Lake Melville) is 54 000 km^ (A). Thus the population estimate for the number of dolphins inside the 200 m depth contour of the aea surveyed was given by A X 2dl = 3486 animals Based on 22 (N) individual sightings, a 95% confi- dence interval for this estimate was 2001 to 4971 animals. The confidence interval was calculated from: A X (-i) A X Since adequate field methods for estimating popu- lations of oceanic dolphins have not yet been perfected, we stress that this population estimate must be viewed with caution. Methods for estimating the number of cetaceans from vessels have primarily focused on tagging or mark-recapture techniques (Jolly 1965; Jones 1977; Seber 1965), both of which were inappropriate given our resources. We had, of necessity, to limit our approach to a population es
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