In 1843, Catholic missionaries chose Dunwich as the site for the first Catholic mission to Australian Aborigines. The sand islands of Quandamooka did not support pasturage suitable for sheep and cattle, and thus there did not occur conversion of large tracts of land into farms and pastoral properties and the subsequent widespread annihilation and displacement of Aboriginal people. The very existence of the quarantine station on Stradbroke Island from 1850 to the 1870s led to the official discouragement of pastoralism or wider settlement for fear of spreading disease. Another reason for discouraging settlement was to reduce the likelihood of incoming vessels to the bay evading customs duty.