. The Canadian field-naturalist. 1994 Dickson: Nesting Habitat of the Red-Throated Loon 11. Figure 1. Location of study area at Toker Point, Northwest Territories. Goose Grass, Puccinellia phryganodes, and Mare's Tail, Hippuris tetraphylla. The study area was searched by observers on foot throughout June and July from 1985 to 1987 to locate all Red-throated Loon nests. After hatch in July, the characteristics of 68 nesting ponds were described: water depth, bottom type, turbidity, % cover with emergent vegetation, percentage of wet shoreline, dominant species of emergent and shore- line vegeta
. The Canadian field-naturalist. 1994 Dickson: Nesting Habitat of the Red-Throated Loon 11. Figure 1. Location of study area at Toker Point, Northwest Territories. Goose Grass, Puccinellia phryganodes, and Mare's Tail, Hippuris tetraphylla. The study area was searched by observers on foot throughout June and July from 1985 to 1987 to locate all Red-throated Loon nests. After hatch in July, the characteristics of 68 nesting ponds were described: water depth, bottom type, turbidity, % cover with emergent vegetation, percentage of wet shoreline, dominant species of emergent and shore- line vegetation, and distance to the nearest pond occupied by another pair of Red-throated Loons. A tape measure was used to determine the maximum water depth for ponds up to 1 m deep. Four cate- gories were used to describe pond depth: m. The surface area of larger ponds was determined from aerial pho- tographs and 1:50 000 scale topographical maps (Canada Map Office, Ottawa). The areas of small ponds < ha in size were determined using pho- tographs taken from a helicopter. An object of a known size was also photographed from the same height to obtain the scale of the photograph. The sur- face area was then calculated using a digitizer. The surface areas of all the other lakes and ponds in the study area (N = 541) were determined using aerial photographs and the following categories: ha. The size frequency distribution of ponds used for nesting was compared to that of lakes and ponds available using the Chi-Square Test. The lakes and ponds occupied by nesting pairs of Pacific Loons, Gavia pacifica, were noted and assigned size categories as above. After hatch, 88 Red-throated Loon nests were described as follows: length, width, height above water, nest material, and whether the nest was a built-up platform or a depression in the ground. Location of the nest on the pond was also described. Nests were classified as either on an island, in off- shore shallow water, on wet shor
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Keywords: ., bookauthorottawafi, bookcentury1900, bookdecade1910, bookyear1919
