London Whaling Convention of 1937

The London Whaling Convention of 1937 was an international attempt to restrain a rapidly expanding industry before its largest targets were exhausted. It set seasonal limits and protections for particular whales, but its reach was compromised by uneven participation and by the continued scale of commercial killing.

Background and Conference

The convention emerged from successive efforts to control whaling as the depletion of whale populations became harder to ignore. An international agreement drafted in 1935 under the auspices of the League of Nations had been ratified by Britain and Norway, the major whaling nations, but its provisions soon appeared insufficient. Britain and Norway sought a wider agreement, and in May 1937 an expanded conference met in London, bringing together representatives from South Africa, the United States, Argentina, Australia, Germany, Ireland, New Zealand, and Norway.

The political setting was uneasy. Britain presented itself as a leading advocate for regulation while acknowledging its own interests, even as diplomacy sought to stabilize a world moving towards war. The Minister of Agriculture and Fisheries, W. S. Morrison, warned the delegates that continued hunting would exterminate the blue whale and soon bring the Antarctic whaling industry to an end. The convention translated that warning into restrictions on seasons, locations, and categories of whale.

Restrictions and Protections

The convention prohibited pelagic whaling for nine months of the year. It also made whaling entirely prohibited in some areas and absolutely protected certain species, whale calves, and females accompanied by calves. Whales below a specified size were protected as well, although the account does not state the threshold. Whaling from land stations, including those in the Southern Hemisphere, was subject to a six-month closed season.

These provisions addressed several points at which industrial hunting could be constrained: the time and place of a hunt, the size of the animal, and its relationship to dependent young. The restrictions were more specific than a general appeal to moderation, but they did not amount to a universal prohibition. The convention’s design depended on governments accepting the terms and applying them within a trade still driven by large-scale extraction.

Reach and Limitations

The conference hoped that other countries, particularly Japan, would join the convention. Japan’s modern whaling industry was expanding rapidly: after adopting techniques learned from Norway, it had begun Southern Ocean voyages by 1934. Japan did not join the international agreements, and its industry prospered; within five years, six Japanese factory ships were operating in Antarctic waters. The convention therefore confronted a central weakness of international controls: important participants could remain outside them while continuing to exploit the same waters.

Even among countries that accepted controls, regulation coexisted with heavy catches. In 1939, a Norwegian captain was prosecuted for killing a fifty-nine-foot female blue whale, below the stated seventy-foot limit. Yet Britain and Norway together remained responsible for ninety-five per cent of an annual toll of thirty thousand whales. Catcher boats could fire from the elevated prows of their ships, leaving the whale little chance to fight back. The contrast between formal limits and continuing mass killing makes the convention’s achievement difficult to separate from its insufficiency.

Conservation Significance

The convention belongs to a larger shift from treating whales principally as industrial resources toward recognizing the need to preserve populations. Its protections for calves, mothers, and undersized animals anticipated the importance of reproduction to survival, but the later evidence in the account shows how severe the conservation problem remained. The North Atlantic right whale, already protected from hunting in 1935, numbered fewer than four hundred; despite legislation and instructions requiring vessels to remain five hundred yards away, its population remained static and its restricted gene pool threatened its future.

That later crisis does not establish that the 1937 convention caused or resolved the right whale’s condition. Rather, it illustrates the distance between declaring protection and securing a species’ survival amid continued human pressures. The convention marked a consequential attempt to make whaling subject to shared limits, while the persistence of depleted populations and the expansion of fleets showed that rules alone could not reverse the consequences of industrial hunting.