CANBERRA, June 30 (Xinhua) -- Two Australian fisheries have been praised by the United Nations (UN) for their ecologically sustainable practices in prawn farming.

    The UN's Food and Agriculture Organization said on Tuesday Australia's Northern Prawn Fishery and Spencer Gulf Prawn Fishery are "global models for many aspects of fisheries management".

    The Northern Prawn Fishery, with an annual production value of more than 60 million Australian dollars (48.7 million U.S. dollars), harvests prawns from an ocean fishing ground that extends from Weipa in northern Queensland to Cape Londonderry in northern Western Australia.

    "To set harvest levels that maintain productive prawn stocks while maximizing fishery returns," Oceans Flagship scientist Cathy Dichmont said.

    The fishery conducts annual surveys to help monitor prawn numbers.

    Meanwhile, the Spencer Gulf Prawn Fishery in South Australia, with the world's largest known population of western king prawns, has introduced technological advances in the way the catch is handled.