Recent analyses of anthropogenic impacts to marine systems have shown the Ross Sea to be the least affected stretch of ocean on Earth, although historical effects were not included in the study. Herein the literature is reviewed to quantify the extent of extraction of biological resources from the Ross Sea continental shelf and slope beginning at the start of the 20th century; none preceded that. An intense extraction of Weddell seals Leptonychotes weddellii by the heroic expeditions and then by New Zealand to feed sled dogs in the 1950-80s caused the McMurdo Sound population to permanently decrease; otherwise no other sealing occurred. Blue whales Balaenoptera musculus intermedia were extirpated from waters of the Shelf Break Front during the 1920s, and have not reappeared. Minke whales B. bonaerensis likely expanded into their vacated habitat, but were then hunted during the 1970-80s; their population has since recovered. Some minke whales are now taken in “scientific whaling”, twice more from the slope compared to the shelf. Other hunted cetaceans never occurred over the shelf and very few ever occurred in slope waters, and therefore their demise from whaling does not apply to the Ross Sea. No industrial fishing occurred in the Ross Sea until the 1996-97 austral summer, when a fishery for Antarctic toothfish Dissostichus mawsoni was initiated, especially along the slope. This fishery has grown since then with effects on the ecosystem recently becoming evident. There is probably no other ocean area where the details of biological exploitation can be so elucidated. It does appear that the Ross Sea continental shelf remains the least affected of any on the globe; the same can not be said of the slope.
A history of the exploitation of the Ross Sea, Antarctica
Numéro du document:
WG-EMM-09/P03
Point(s) de l'ordre du jour
Publication:
(Polar Rec., in press)
Résumé