International Convention for the Regulation of Whaling

The International Convention for the Regulation of Whaling (ICRW) is an international environmental agreement aimed at the "proper conservation of whale stocks and thus make possible the orderly development of the whaling industry". It governs the commercial, scientific, and aboriginal subsistence whaling practices of 88 member nations.
The convention is a successor to the 1931 Geneva Convention for Regulation of Whaling and the 1937 International Agreement for the Regulation of Whaling, established in response to the overexploitation of whales in the post-World War I period. Neither instrument was effective, but each provided the framework for the ICRW, which was spearheaded by the United States and signed by 15 nations in Washington, D.C. on 2 December 1946; the convention took effect on 10 November 1948. A protocol broadening the scope of the convention's enforcement was signed on 19 November 1956. 
The objectives of the ICRW are to protect all whale species from overhunting; establish a system of international regulation for whale fisheries to ensure proper conservation and development of whale stocks; and safeguard for future generations the important natural resources represented by whale stocks. The primary instrument implementing these aims is the International Whaling Commission, established by the convention as its main decision-making body. The IWC meets annually and adopts a binding "schedule" that regulates catch limits, whaling methods, protected areas, and the right to carry out scientific research involving the killing of whales.
Members.
As of January 2021, there are 88 parties to the convention. The initial signatories were Argentina, Australia, Brazil, Canada, Chile, Denmark, France, the Netherlands, New Zealand, Norway, Peru, South Africa, the Soviet Union, the United Kingdom and the United States.
Although Norway is party to the convention, it maintains an objection to the 1986 IWC global moratorium does not apply to it.
Withdrawals.
Eight states withdrawn from the convention since its ratification: Canada, Egypt, Greece, Jamaica, Mauritius, Philippines, the Seychelles and Venezuela. 
Belize, Brazil, Dominica, Ecuador, Iceland, Japan, New Zealand, and Panama have all withdrawn from the convention temporarily but ratified it second time; the Netherlands, Norway, and Sweden have each withdrawn from the convention twice, only to have accepted it a third time.
Japan is the most recent member to depart, in January 2019, so as to resume commercial whaling.
Effectiveness.
There have been consistent disagreement over the scope of the convention. The 1946 Convention does not define a 'whale', and some members IWC has the legal competence to regulate catches of only these named great whales (the baleen whales and the sperm whale). Others believe that all cetaceans, including the smaller dolphins and porpoises, also fall within IWC jurisdiction.
An analysis by the Carnegie Council determined that while the ICRW has had "ambiguous success" owing to its internal divisions, it has nonetheless "successfully managed the historical transition from open whale hunting to highly restricted hunting. It has stopped all but the most highly motivated whale-hunting countries. This success has made its life more difficult, since it has left the hardest part of the problem for last." 