The Impact of Disused Whaling Stations in Peri Antarctic Islands

South Georgia was the first land to be sighted south of the Antarctic Convergence when, in 1675, a London merchant rounding Cape Horn was blown off course during a storm. Later, the abundance of fur and elephant seals described in the account of Cook's voyage spurred the 1785 "gold rush" of sealers. Intense exploitation led to the virtual extermination of South Georgia fur seals by about 1810. Subsequent recovery of seal populations yielded lesser fur-sealing peaks in about 1820 and 1870. Elephant seals also were exploited for oil. Within the framework of the International Polar Year, a German scientific expedition operated a station at South Georgia in 1882 and 1883. The Norwegian whaling industry began to permanently settle the island in 1904, and six shore-based stations and eight floating factories operated up to 1917. Although sealing ceased in 1913, more than 175,000 whales were killed in this period. At this time, South Georgia also became "a Gateway to Antarctica"; two of Shackleton's expeditions, for instance, visited the island, where the explorer died and was buried. In 1925 the British Government established a scientific station on the island, but Norwegian and then Japanese whaling at South Georgia stopped only in 1965. On 3 April 1982 South Georgia become the only part of Antarctica ever directly involved in warfare (cf. the Argentinean attack of the UK scientific station at King Edward Point, which was recaptured by the Royal Navy on 25 April). For over a century South Georgia was the site of many events, as documented by the presence of a military base, sunken whalers along the seashore, derelict whaling stations, and newly introduced mammals such as reindeers, brown rats and mice.

Platt and Mackie (1979, 1980) analysed hydrocarbons in a sediment core from King Edward Cove (South Georgia), extending from the present-day to the early 1800s. They identified the temporal trend of hydrocarbon pollution associated with whaling activity. Cripps (1989) found that quantities of fuel oil, lubricant and whale oil were still present in South Georgia whaling stations, and that these contaminants leaked into terrestrial and marine environments. He collected samples of seawater from both control and more impacted sites, and found different n-alkane distribution patterns. Three sites were clearly contaminated (total concentrations of n-alkanes in seawater ranged from 7.5 to 10.1 |g l-1) by weathered and degraded fuel oil or by tar. Several PAHs were detected, and phenanthrene, anthracene, fluoranthene and pyrene occurred in all seawater samples. The maximum total PAH concentration (1.2 |g l-1) was measured in a sample from a cove adjacent to the Strom-ness abandoned whaling station.

Whaling at Signy Island (South Orkney Islands) commenced in 1907. Although a shore whaling station was built in 1921, it only operated for a few years; for about 20 years, most whaling activity was performed on floating factory ships anchored in Factory Cove. Since 1947 the British Antarctic Survey has maintained a research station at the site previously occupied by the whaling station. To evaluate the extent of contamination from the station, Cripps (1992a) measured concentrations of n-alkanes and PAHs in seawater and sediments. He found that total n-alkane concentrations in seawater decreased from 7.6-2.6 |g l-1 within 500 m of the station. In contrast, although total PAH concentrations (from 110-216 ng l-1) were slightly higher than in open-ocean waters (about 70 ng l-1), they did not vary with distance from the station. Concentrations of n-alkanes and PAHs in surface sediments (top 2.5 cm) declined within 375 m of the station (from 1,731 and 280 |g kg-1 dry wt. to 64 and 14 |g kg-1 dry wt. respectively). Sediment core profiles revealed no consistent patterns of n-alkanes concentrations. The total PAH content near the station did not change with depth, while at a distance of 250 m it increased with depth. The latter trend was probably due to a small accidental spill in 1965.

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