STUDIES OF WATERFOWL IN BRITISH COLUMBIA GREEN-WINGED TEAL

• Published in: Canadian Journal of Research
• Main Author: Munro, J. A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1949
• Subjects: Pharmacology (medical); Complementary and alternative medicine; Pharmaceutical Science; Pacific; Anas acuta; Alaska
• Online Access: http://dx.doi.org/10.1139/cjr49d-013; http://www.nrcresearchpress.com/doi/pdf/10.1139/cjr49d-013

The migrations of the Pacific Coast population of Anas carolinensis parallel in time and space those of Anas acuta. Both use the same migration routes along the coast and along the main north and south river systems of the interior. So also both nest more commonly in Alaska than elsewhere. The peak of the spring migration usually is reached in late March or early April; the peak of the autumn migration usually is in late October and early November. A relatively large number normally winter on the Coastal Plain. Very few winter in the interior. Study of banding data reveals that (1) autumn transients through the Coastal Plain follow the coast route south to the mouth of the Columbia River and beyond through Oregon and California, rarely passing east of the High Sierras, (2) few individuals among the population following interior routes reach the coast, the tendency being to swing eastward to the Great Basin. The two main flyways through British Columbia, one on the coast the other through the interior, differ in at least one important respect, viz., along the interior route are many more or less isolated areas of suitable nesting grounds whereas on the coast there are none. A small nesting population, fluctuating annually in numbers, is widely distributed through the interior, the center of abundance being the Cariboo Parklands—the term abundance being used in a relative sense. Actually the population is small and dispersed. In the year 1938 a total of only 17 broods was counted on a study area of 60 sq. mi. containing a high average of highly productive waterfowl territory. Smaller counts were made here in each of the years following 1938. Egg-laying begins in May; there is some loss of early clutches through crow predation compensated for by later, and usually more successful, nesting. It is not unusual for females to be incubating a second clutch of eggs in early July. Nest sites are in dry places nearly always adjacent to a small pond or marsh in the grasslands. The earliest and latest dates for records of ...