Bacterial Populations in the Beaufort Sea

Spacial and seasonal variation patterns were studied for bacterial populations in Beaufort Sea ice, water and sediment. Bacterial populations in the Beaufort Sea were found in concentrations as high as are found in temperate oceans. Bacterial populations, especially viable bacteria, were lower in surface water during winter than summer, but not in sediment. Beaufort Sea bacterial populations are mainly psychrotrophic and are clearly adapted to growth at low temperatures. Ice conditions appear to be important in determining levels of bacterial populations in water. RkSUMJ?.. Des variations typiques dans l'espace et suivant les saisons, ont été étudiées, dans les sédiments, l'eau et la glace de la Mer de Beaufort, en ce qui concerne les colonies de bactérie. On a trouvé des colonies bactérielles dans la Mer de Beaufort en concentration aussi importante que dans les océans tempérés. Les populations bactérielles, surtout les bactéries, aptes à vivre, étaient moins nombreuses à la surface de l'eau pendant l'hiver qu'en été mais non dans les sédiments. Les populations bactérielles de la Mer de Beaufort sont surtout psychotrophiques et bien adaptées pout grandir avec des températures glaciales. Les conditions de glace paraissent un facteur important du niveau d'importance des populations bactérielles dans l'eau. Traduit par Alain de Vendegies, Aquitaine Co. of Canada Ltd. previously conducted. This paper describes a survey of the distribution of bacterial populations in the western Beaufort Sea. This is part of a larger study aimed at characterizing the bacterial populations in this area. Bunch and Harland (1976) reported that surface waters in the Mackenzie Delta region of the Canadian Beaufort Sea contain lo3 - 104 viable bacterialml, which they reported to be mainly psychrophilic. Viable bacterial populations in surface waters of polynias in the central Arctic Ocean have been reported to be less than 1 per ml (Kriss, 1963). Kriss (1963) also reported that viable bacterial populations in the Arctic Ocean near Greenland are less than llml in surface water. Boyd and Boyd (1963) enumerated bacteria from nearshore water samples collected during summer in the Chukchi Sea just west of the Chukchi-Beaufort Sea interface. They reported that bacterial numbers were lower in this area than in temperate region seas and postulated that most of the micro-organisms were of terrestrial origin. Horner and Alexander (1972)