Later that year Lieutenant Richard Williams, who had received his promotion on 13 December 1804, assumed command, after serving as a Master's Mate on Isis.

For his services he received the thanks of Admiral Sir Andrew Mitchel, chief of the Halifax, Nova Scotia, station.

Late in the year Lieutenant Thomas Lee assumed command and sailed her on the Newfoundland station on coast patrol and fisheries duties.

[6][7][a] As Mackerel left New York on 18 June she passed the USS United States under Captain Stephen Decatur.

[8] She was still at Portsmouth on 31 July when the British authorities seized the American ships there and at Spithead on the outbreak of the War of 1812.

[b] On 14 August Mackerel accompanied Admiral Sir John Borlase Warren, who was sailing to Halifax, Nova Scotia, on San Domingo, together with Poictiers, Sophie, and Magnet.

[1] This article includes data released under a Creative Commons Attribution-ShareAlike 3.0 Unported UK: England & Wales Licence, by the National Maritime Museum, as part of the Warship Histories project.