Showing papers on "Beluga published in 1990"
TL;DR: The reason for higher levels of TCDD and OCDD in the Arctic than in the sub-Arctic is suggested to be trans-polar movement of aerosols with combustion-related origins in Eurasia.
126 citations
TL;DR: For example, during aerial surveys in 1986 of whales migrating in Lancaster Sound, this article observed newborn narwhals as early as 27 May and regularly thereafter, and Beluga calves were first seen on 31 May and were seen sporadically throughout the study period.
Abstract: During aerial surveys in 1986 of whales migrating in Lancaster Sound, we observed newborn narwhals as early as 27 May and regularly thereafter. Beluga calves were first seen on 31 May and were seen sporadically throughout the study period. These observations represent the earliest reported sightings to date of newborn narwhals.
6 citations
TL;DR: The hybrid beluga × sterlet is fully fertile and artificial propagation of bester and other sturgeons is possible without difficulties by means of injection of pituitary glands or releasing hormones, and in the field of sturgeon nutrition further investigation is desirable.
6 Sep 1990
TL;DR: Two Great Polar Bear Hunters on Abstract King Island involve the spirit of the arctic wilderness in a tale of polar bear hunting.
Abstract: Abstract King Island, located in the Bering Straits midway be tween Alaska and Siberia, is inhabited by a small permanent population of Inupiat Eskimos. These residents rely on marine resources, including bowhead and beluga whales, walrus, migratory birds, and seals, to sustain themselves. In this story Aloysius Pikonganna (1909-1986) evokes the mysterious spirit of the arctic wilderness in the form of an immense polar bear hunted by two King Islanders on the ice pack.
1 Jan 1990
TL;DR: In this article, a 3 stage, length-based model composed of newborns, juveniles and adults was applied to length frequency data from aerial photographic censuses to provide an alternate method of demographic analysis when harvests are small or absent.
Abstract: The vital rates of beluga, Delphinapterus leucas, harvested in northern Quebec are within the range reported by previous studies in Alaska and the Canadian and Soviet Arctic. Small sample size and inadequate estimates of survivorship rates prevent meaningful calculation of population growth rate. The pattern of changes in vital rates over the life cycle of beluga and analysis of errors associated with stage classification indicate that the demographic information in a 6 x 6 age-grouped Lefkovitch matrix is similar to that in a 38 x 38 age class Leslie matrix. A 3 stage, length-based model composed of newborns, juveniles and adults contains less demographic information than the larger matrices, but is superior to a juvenile/adult classification scheme. The 3 stage model applied to length frequency data from aerial photographic censuses should provide an alternate method of demographic analysis when harvests are small or absent. Colour is a poor criterion for stage classification.