Chaser (or Chacer) first appeared under that name in British records in 1786. She had been launched in 1771 at Philadelphia under another name, probably Lord North. Lord North became Cotton Planter, and then Planter, before she became Chaser. Between 1786 and 1790 Chaser made four voyages as a whaler in the British southern whale fishery. She then became a merchantman. In 1794 a privateer captured her but the Spanish recaptured her. She became a Liverpool-based slaver. In 1796 she was condemned in West Africa on her first voyage in the triangular trade before she could embark any enslaved people.