The civil War did a lot to decrease the size of the whaling fleet
The decline in the available population did a lot more to decrease the size of the whaling fleet. The London whalers were down after 1813, but not out. With several nations' whaling fleets in operation in large numbers from 1815 onward, and with each ship hoping to take from 30 to 40 "old bulls" in a three year voyage, 100,000 or more whales, most of them large males, were taken each decade. By the time the Civil War in the United States began, more than a half-million whales had been taken in the South Sea "fishery," and once again, most of those were the identifiable large males. This had an obviously drastic effect on breeding viability of the sperm whale. Keep in mind that when USS Essex
devastated the London whalers, she did so by taking 15 prizes in six months time, and not all of those were whalers. From the perspective of a frigate taking prizes, that was wonderful work (and doubtless made the captain and crew a considerable amount of money, including Midshipman David Farragut, the future hero of the U.S. Navy in the Civil War); from the perspective of the size of the South Seas whaling fleet, it shows just how small that fleet was in 1813. At the point at which there were 750 whalers out there, the "resource harvesting" area of the trade was saturated--it was a case of far too many would be profiteers chasing a dwindling resource. Sperm whales were first taken in the North Atlantic (where they were in relatively small numbers) in the 18th century, and the relatively small population was followed into the South Atlantic. By the end of the 18th century, the commercial whale fisheries of the North Atlantic were just about played out, and the American, English and French fleets had transferred almost completely to the South Atlantic.
By that time, the size of the whaling fleets was increasing, both because of the more wide-spread use of whale products by consumers and industry, and because of the success of the American revolution had lead to a burgeoning and vigorous competition with the English on the part of Americans. In 1786, James Colnett, who had sailed as a midshipman with James Cook on the second voyage, was fitted out for an expedition to the Pacific Northwest of North America, because of the value of the sea otter pelts (highly valued in China) which had been obtained during Cook's third voyage. The expedition was intended to pay its own costs, and even to make a profit, by taking whales along the way, and especially by taking or trading for sea otter pelts on the northwest coast.
Colnett's voyage, although attempted on the cheap, was nonetheless outfitted according to Royal Navy standards, and Colnett was seconded by competent officers and petty officers, and Captain Colnett himself kept the kind of meticulous records for which James Cook had been justfiably famous. The most important effect (an unintended consequence) of Colnett's voyage was to develop the South Seas whale fishery. After the War of 1812, New England whalers went out in numbers sufficient to dwarf the entire number of English and French whalers combined.
The Civil War did not so much decrease the size of the whaling fleet as it reduced it to reasonable levels. The frenzy to profit from the Pacific sperm whale fishery had already died away. As FM points out, it was an expensive undertaking--a sharp case of being obliged to spend money in order to make money, and the money needed to be spent up front. Whaling crews did not need to be paid, they took shares of the catch, so the high costs were entailed in outfitting the vessel and provisioning the ship before it sailed. Once at sea, no further costs were necessarily entailed, although storm damage might require the master to draw on letters of credit to get materials for repair in Valparaiso. That port, however, was notorious for not having what was needed, and for charging astronomical prices for what was available. Most whalers operated on military principles, and took as much sail cloth, cordage and spars as could reasonably be packed into the hold along with the barrels for the whale oil. The chase for the wild profits of the sperm whale fisheries was already in decline when Drake started drilling in Titusville.
At all events, FM's information confirms what i pointed out, which is that initially
, primitive petroleum distillates did not provide the lubricants necessary to replace the use of whale oil in industry. But as for the size of the whaling fleet, as is the case in so many commercial frenzies, by the time it had increased to over 500 ships, and by the time whalers were chasing after whales as far west as the coasts of New Zealand and Australia, and as far north as the coasts of Japan and Alaska, the enterprise was already being overworked. By 1850, the whaling fleets of the world had already begun to rapidly decline, because it had become a matter of luck whether or not a ship could find enough whales to fill its hold before the hundreds of other whalers showed up to exploit the whales that ship had found. Like the "dot-com" boom or the sub-prime mortgage scam, whaling became such a hot commercial venture that people rushed to capitalize whaling operations and outfit ships at the very time when the sheer numbers of whalers at sea were making it unprofitable.