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controlled seal harvesting, the British government began issuing quotas in 1910 for the exploitation of elephant seals on South Georgia. Only bull males were to be taken, and then only to the extent that sufficient numbers remained on the beaches to reproduce with their harems. These regulations, which were implemented as the first Antarctic resource conservation strategy, included a limit of 6000 bulls per year as well as specified sealing zones and seasons (Fig. 10.2). This elephant sealing industry continued until 1964, when it collapsed along with the Antarctic whaling industry.

None of the other four Antarctic seal species have been the focus of commercial harvesting. In view of harvesting the most abundant resources first, this absence of commercial interest is particularly interesting with respect to the crab-eater seal (Lobodon carcinophaga), which alone accounts for more than half of the seals on Earth. The Weddell seal (Leptonychotes weddelli) is the next most abundant Antarctic seal, with an estimated population size of 730,000 (Plate 7). Localized impacts on Weddell seal populations around Antarctica had occurred in relation to their utilization as food for dog teams until the late 1980s. The leopard (Hydrurga leptonyx) and Ross (Ommatophoca rossii) seals constitute slightly more than 2% of the Antarctic seal population and never have been harvested.

The presence of large rookeries in the vicinity of sealing and whaling enterprises, on subantarctic islands near the Antarctic Convergence (Fig. 8.3), also made penguins easily accessible targets. Penguins were killed to make clothing from their skins and fuel oil from their blubber, while their eggs were collected for food.

The king penguin (Aptenodytes patagonicus), because of its large size and thick layer of blubber, was harvested in great quantities. More than 400,000 king penguins were reported to have been killed in the Falkland Islands in 1867 alone. Similar levels of harvesting for the combined populations of king, macaroni (Eu-dyptes chrysolophus), and gentoo (Pygoscelis papua) penguins also have been reported for South Georgia.

However, the most extreme episode of penguin harvesting began on Macquarie Island in 1891 under a lease from the government of New Zealand. This industry initially focused on the king penguin and eventually shifted to the royal penguin (Eudyptes schlegeli). More than 150,000 penguins were killed per year on Mac-quarie Island until public outrage forced the New Zealand government to withdraw the lease in 1916.

Egg collecting also had an impact on penguin populations around Antarctica. On the Falkland Islands, for example, more than 13,000 rockhopper penguin (Eu-dyptes chrysocome) eggs were removed in a single day from a 2-kilometer stretch of cliff. Until recently, more than 10,000 gentoo penguin eggs have been collected each year by the people living on the Falkland Islands during the annual ''egging picnic'' on November 9th. As a consequence of harvesting the adults and collecting their eggs, penguin populations have been reduced or eliminated around Antarctica. These impacts are reflected in the populations of king penguins, which have greatly decreased on Macquarie Island, South Georgia, and the Kerguelen Islands and have completely vanished from the Falkland Islands.

Whaling in Antarctica began in 1904 with the establishment of a station at Stromness, South Georgia, by the Norwegian C. A. Larson. During the first year a single ship captured 195 whales (Fig. 10.3) from among more the million estimated in the Antarctic region (Table 10.1). The Antarctic whaling industry grew rapidly, and by 1912-1913 there were six land stations with 21 factory ships that captured 10,760 whales. All of the early Antarctic whaling was conducted in the Falkland Island Dependencies, which belonged to the United Kingdom (Chapter 3: Terra Australis Incognita).

To avoid government regulations, such as the licenses for elephant seals, a new type of whaling vessel was created in 1925. Whales could be brought onto ships by a slipway at the stern and then processed without returning to the land stations. This technological advance further increased whaling activity such that in 193031 more than 37,500 whales were taken by 205 catchers—yielding more than 570,000 tons of whale oil and causing the collapse of the world market for whale oil in 1931.

Initially, the humpback whale (Megaptera novaeangliae) was taken because of its abundance near islands—for much the same reason that the seals and penguins were first exploited. As the humpback populations declined, fishing for the blue (Balaenoptera musculus) and fin (Balaenoptera physalus) whales increased. The fishery for fin whales continued beyond the collapse of the blue whale populations until it also was replaced by fisheries for the sei (Balaenoptera borealis) and sperm (Physeter macrocephalus) whales. During the 1990s, Japan and Norway began harvesting the small minke whale (Balaenoptera acutorostrata) in opposition to the international moratorium on all commercial whaling activities that began in 1986.

FIGURE 10.3 Annual catches of the great whales in the Antarctic marine ecosystem, showing the progressive depletion (diagonal line) of the different species during the 20th century. The whaling hiatus between 1940 and 1945 was due to World War II. These whaling activities have reduced the overall biomass among all whale species by more than 80% and among the humpback (Megaptera novaeangliae) and blue (Balaenoptera musculus) whales by more than 95% (Tables 10.1 and 10.2). The dashed line from the minke whale (Balaenoptera acutorostrata), among the smallest baleen whales, represents ongoing discussions about its future exploitation since the larger species no longer are commercially viable. Modified from Gambell (1985) and Berkman (1992).

Year

FIGURE 10.3 Annual catches of the great whales in the Antarctic marine ecosystem, showing the progressive depletion (diagonal line) of the different species during the 20th century. The whaling hiatus between 1940 and 1945 was due to World War II. These whaling activities have reduced the overall biomass among all whale species by more than 80% and among the humpback (Megaptera novaeangliae) and blue (Balaenoptera musculus) whales by more than 95% (Tables 10.1 and 10.2). The dashed line from the minke whale (Balaenoptera acutorostrata), among the smallest baleen whales, represents ongoing discussions about its future exploitation since the larger species no longer are commercially viable. Modified from Gambell (1985) and Berkman (1992).

TABLE 10.1 Estimates of Whale Populations before 1904ab

Whale characteristics Whale food consumption

TABLE 10.1 Estimates of Whale Populations before 1904ab

Whale characteristics Whale food consumption

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