The last colony of great auks lived on Geirfuglasker (the "Great Auk Rock") off Iceland. This islet was a volcanic rock surrounded by cliffs that made it inaccessible to humans, but in 1830, the islet submerged after a volcanic eruption, and the birds moved to the nearby island of Eldey, which was accessible from a single side. When the colony initially was discovered in 1835, nearly fifty birds were present. Museums, desiring the skins of the great auk for preservation and display, quickly began collecting birds from the colony. The last pair, found incubating an egg, was killed there on 3 July 1844, on request from a merchant who wanted specimens, with Jón Brandsson and Sigurður Ísleifsson strangling the adults and Ketill Ketilsson smashing the egg with his boot.
Great Auk specialist John Wolley interviewed the two men who killed the last birds, and Sigurður described the act as follows:
The rocks were covered with blackbirds [referring to Guillemots] and there were the Geirfugles ... They walked slowly. Jón Brandsson crept up with his arms open. The bird that Jón got went into a corner but [mine] was going to the edge of the cliff. It walked like a man ... but moved its feet quickly. [I] caught it close to the edge – a precipice many fathoms deep. Its wings lay close to the sides - not hanging out. I took him by the neck and he flapped his wings. He made no cry. I strangled him.