a small number of slaves. Although by the turn of the 19th century they were turning some profit through the sale of ivory, the Portuguese' main purpose for maintaining the fort was to prevent the Austrians or the British from reasserting themselves in the bay. If it were not for the Portuguese Crown's insistence on maintaining the fort, the colonial government on Mozambique Island would likely have abandoned the struggling settlement. The Portuguese briefly abandoned Lourenço Marques after a French attack in 1796, returning in 1799. In 1801, the small Portuguese garrison was unable to prevent an English ship from trading in Delagoa Bay. Though there is limited documentation of this period, it is thought that very little trade was carried out in the bay during the first two decades of the 19th century. The next British ship to enter the bay was 14 years later in 1815, by which point the Portuguese were able to successfully turn them away. Much of the economic activity that remained in this period consisted of visits by whaling ships stopping for provisions. French and British whaling ships had been stopping at the port since 1789, and while French ships were no longer welcome after having attacked the fort, British and American whaling vessels continued to resupply at the bay through the early 19th century. By 1817, the Portuguese planned to use the port to enter the whaling industry. That year, their first attempt to establish a whaling company in Delagoa Bay failed when their representative alienated a local Tembe chief by neglected to ask permission to use the tribe's land. The chief ended up killing the Portuguese men involved. With the second attempt in 1818, the whaling company was established, with black harpooners and specialized equipment brought in from North America. By this period, the slave trade in Mozambique was found up north, and in Delagoa Bay it was nearly nonexistent, perhaps being a factor in the Portuguese search for other ventures like whaling. By the 1820s, the slave trade had grown in Delagoa Bay, but was still small compared to the north. Portuguese colonization and territorial disputes, 1820–1900 British claims and African upheaval, 1820s Beginning in 1821, Captain William Fitzwilliam Owen was sent by the British to survey the East African coast. Upon visiting Delagoa Bay, Owen wrote to his superiors that the Portuguese fort there was still so isolated as to