The most productive part of the South Atlantic lies south of latitude 50° S., where active operations extend to and even beyond the Antarctic circle. It appears to be the general rule in Antarctic waters that whales are more numerous the closer the association with ice conditions, and there seems to be reasonable grounds for supposing that this may explain the comparatively few whales sighted by Expeditions which have explored the more northerly and more open seas, while the whalers themselves have even asserted that their poor seasons have nearly always coincided with the absence of ice, or with poor ice conditions. At all events, those Expeditions which have penetrated far south and well into the pack-ice have, without exception, reported the presence of whales in large numbers, even in the farthest south latitudes, so that our knowledge of the occurrence of whales in the Antarctic has been largely derived from these Expeditions, whose main object was either the discovery of new land or the Pole itself. The largest number of Antarctic Expeditions has concentrated on the two areas of the South Atlantic and the Ross Sea, and the records of the occurrences of whales have, in consequence, been concentrated in these two localities. In the intervening areas, however, Expeditions, notably the Belgica on the western side and the Gauss on the eastern side of the Antarctic continent, have reported whales in moderately large numbers, so that the stock is by no means confined to the two areas above mentioned.
The effective fishing area may be assumed to lie within a radius of a hundred miles from each shore station and floating-factory anchorage, and a rough estimate of all the Falkland stations works out at 160,000 square miles. The total for the whole Falkland area is about 2,000,000 square miles, which is roughly less than a sixth of the total Antarctic sea area. The question then arises as to how far the “catch percentage” during the short fishing season affects the total stock, but so far one can only conjecture as to the actual results from a comparison of the numbers seen, chiefly by scientific and other Expeditions, in areas outside the intensive fishing area with the numbers and percentage of each species captured in the intensive fishing area. Sufficient evidence, however, seems to point quite definitely to one species—the humpback—being in danger of extermination, but the blue and fin whales—the other two species of rorquals which form the bulk of the captures—appear to be as frequent now as they have ever been.
The whales captured at the various whaling-stations of the Falkland area are confined largely to three species—blue whale (Balaenoptera musculus), fin whale (Balaenoptera physalis), and humpback (Megaptera nodosa); sperm whales (Physeter catodon) and right whales (Balaena glacialis) being only occasional and rare captures, while the sei whale (Balaenoptera borealis) appeared in the captures at South Georgia in , and now forms a large percentage of the captures at the Falkland Islands. During the earlier years of whaling at South Georgia, and up to the fishing season –, humpbacks formed practically the total catch. In – the following were the percentages for the three rorquals in the captures at South Georgia and South Shetlands:
Humpback 38 percent, fin whale 36 percent, blue whale 20 percent. Of late years the percentages have altered considerably, blue whales and fin whales predominating, humpbacks decreasing rapidly. In , the South Georgia Whaling Company (Messrs. Salvesen, Leith) captured 1085 whales, consisting of 15 percent humpback, 25 percent fin whales, 58 percent blue whales, and 2 right whales. In the same year the captures of three companies at the South Shetlands gave 1512 whales, and the percentages worked out at 12 percent humpbacks, 42 percent fin whales, and 45 percent blue whales. In , the Southern Whaling and Sealing Company captured (at Stromness, South Georgia) 529 whales, of which 2 percent were humpbacks, 51 percent fin whales, and 45 percent blue whales. These captures do not represent the total catch, but are sufficiently reliable to show how the species are affected. The reduction in numbers of the humpback is very noticeable, and even allowing for the possible increase in size of gear for the capture of the larger and more lucrative blue and fin whales, there is sufficient evidence to warrant the fears that the humpback stock is threatened with extinction.
In the immediate northern areas—in the region from latitude 50° S. northward to the equator, which is regarded as next in importance quantitatively to the sub-Antarctic, though nothing like being so productive, the captures are useful for a comparative study in distribution. At Saldanha Bay, Cape Colony, in , 131 whales were captured and the percentages were as follows: 35 percent humpback, 13 percent fin whale, 4 percent blue whale, 46 percent sei whale, while nearer the equator, at Port Alexander, the total capture was 322 whales, and the percentages gave 98 percent humpback, and only 2 captures each of fin and sei whales. In , at South Africa (chiefly Saldanha Bay and Durban), out of a total of 839 whales 60 percent were humpback, 25 percent fin whales, and 13 percent blue whales. In , out of a total of 853 whales 10 percent were humpback, 13 percent fin whales, 6 percent blue whales, 68 percent sperm whales, and 1 percent sei whales. In Chilian waters, in , a total of 327 whales gave 31 percent humpbacks, 24 percent fin whales, 26 percent blue whales, 12 percent sperm whales, and 5 right whales. There seems then to be a definite interrelation between the two areas.
