Whaling commenced in New Zealand waters only 22 years after Captain Cook's first voyage to New Zealand. The first recorded whale ship was the William and Ann under the command of Captain William Bunker, who called at Doubtless Bay in 1791 during a sperm-whaling voyage in the Pacific Ocean. His was the forerunner of a large number of ships of different nationalities which either whaled in New Zealand waters or called at the ports for provisioning as part of sperm-whaling operations during the following hundred years.

During 1801 there were reports of three sperm whalers which returned from the New Zealand grounds as full ships, while six others were still operating off northern New Zealand as pelagic whalers, that is, catching off shore in the open ocean. By 1805 vessels were calling regularly at the Bay of Islands primarily for taking on water and any fresh food which could be bartered from the local Maoris, but, at the same time, some Maoris were occasionally taken on as members of the crew and the development of the Bay of Islands as a provisioning, refitting, and recruiting centre had commenced.

Despite the great predominance of American whalers (from New England ports) in the Pacific Ocean throughout the nineteenth century, it was British and Australian whalers who dominated whaling in New Zealand waters until 1835. American whalers had been excluded from Australian ports until 1831, and for a considerable time they operated mainly in the eastern, mid, and north Pacific closer to other bases. Meanwhile, British and colonial spermwhaling vessels in New Zealand waters increased steadily. During one month, March 1833, 27 British and colonial vessels, mainly whalers, were recorded at the Bay of Islands. Substantial numbers of whalers from France and a few from Bremen and Portugal added to the above. Occasional American whalers had called during the early nineteenth century, but from 1835 American whalers arrived in rapidly increasing numbers to join in the right whale fishery established shortly before in bays. They also hunted right whales off shore as well as sperm whales on the high seas.

In the peak year, 1839, Clendon, the American Consul at the Bay of Islands, entered 62 American ships and, although this included a few repeat visits in the year, many American whale ships used other New Zealand ports. Some vessels caught whales off shore from New Zealand but did not enter any New Zealand ports. It is impossible to give a precise figure for the total number of vessels which whaled off New Zealand during 1839, but it was probably of the order of 150 American and up to 50 or more vessels of other nationalities. This is much less than the clearly inaccurate figure of 600 American vessels off New Zealand, sometimes quoted (the peak fleet for the entire Pacific Ocean was 760), but it nevertheless shows that whaling was being carried out on a very substantial scale. Annual catches for individual vessels ranged from nil to 10 or more, but returns were usually recorded in barrels of oil instead of numbers of whales. It is a hazardous exercise to attempt to estimate the total number of whales caught per year, but in a few peak years this probably exceeded 1,000 whales (both sperm and right) in New Zealand waters.

Pelagic whaling dropped sharply in 1841, the year following the Treaty of Waitangi which established British sovereignty, with the accompaniment of port dues and excise duties. But it rose to a second and lower peak in 1846 and then declined to a relatively small scale as right whales had become depleted around New Zealand and new whaling grounds for sperm and other whales had been opened up elsewhere.