General introduction to the marine flora and fauna of the Albany area

Abstract

The state of Western Australia occupies an area of 2.5 million square kilometres, one-third of the total size of the continent, and has a coastline of 12,500 km. Western Australia ranges from latitude 14ºS to 35ºS, a latitudinal range of 21º (Figure 1). Three major marine biogeographic zones occur in the state. The north coast, from North West Cape northeastward to the Northern Territory border, has a tropical fauna that is part of the vast Indo-West Pacific biogeographic region. Many of the species extend across the north of the continent from Western Australia to Queensland. The south coast of Western Australia, from Cape Leeuwin east to the South Australian border, has a temperate fauna that is continuous with that of the remainder of southern Australia. Southern Australian temperate species may extend as far eastwards as New South Wales or even southern Queensland. The west coast of Western Australia, between Cape Leeuwin and North West Cape, is a biogeographic overlap zone, with a transition between tropical species in the north and temperate species in the south. In addition to tropical and temperate species, the shallow waters of the Western Australian coastline also have a number of species endemic to the state. Most of the endemic species have at least part of their distribution on the west coast of the state, but they may extend onto either the south or the north coast; a few occur from the south coast, over the entire west coast, to the north coast. The proportion of endemic species varies between taxa (Wilson and Gillett, 1971; Marsh, 1976; Wilson and Stevenson, 1977; Wells, 1980).