Aliens in the Antipodes: Non-indigenous Marine Crustaceans of New Zealand and Australia

Abstract

New Zealand and Australia have a relatively short history of European colonisation, going back little more than two centuries. Otherwise, the first human settlement in the region dates back to less than 1,000 years (New Zealand) and 40,000 years (Australia). Although alien species no doubt arrived with the first human settlers, the bulk of marine species alien to Antipodean shores have arrived in the last 200 years. The geographically isolated positions of New Zealand and Australia, relative to major population centres in the northern hemisphere, has made the region one of the last to be reached by European exploration of past centuries. Thus, Australia and New Zealand have a relatively short history of marine invasion. This study surveys the current state of knowledge of alien Crustacea in the Antipodes. To date, 112 and 41 alien or cryptogenic marine crustacean species have been recorded from New Zealand and Australia waters, respectively, of which 28 and 38 are established. In addition, three alien chelicerate species have been recorded from New Zealand. The majority of these probably arrived as stowaways amongst hull fouling and solid ship ballast (in the earliest days). Others have arrived as larvae in ballast water or have been deliberately introduced. Whereas the environmental impact of many alien Crustacea remains unknown, some species have become important pests.