Sealing at Heard Island lasted from 1855 to 1910, during which time 67 sealing vessels are recorded visiting, nine of which were wrecked off the coast. Relics that survive from that time include trypots, casks, hut ruins, graves and inscriptions. This caused the seal populations there to either become locally extinct or reduced to levels too low to exploit economically. Modern sealers visited from Cape Town in the 1920s. Since then the populations have generally increased and are protected. Seals breeding on Heard include the southern elephant seal, the Antarctic fur seal and the subantarctic fur seal. Leopard seals visit regularly in winter to haul-out though they do not breed on the islands. Crabeater, Ross and Weddell seals are occasional visitors.