Review of an acoustic alarm strategy to minimise bycatch of humpback whales in Queensland coastal gill net fisheries

Abstract

Humpback whales, Mega pi era novaeangliae, in Queensland coastal waters arc at risk of entanglement in a range of fishing gears and obstacles. Since 1991 the Queensland Shark Control Programme of the Queensland Department of Primary Industries has developed an acoustic alarm bvcatch reduction strategy. Four acoustic alarm types attached to gillnets have been utilised in an attempt to ‘warn’ humpback whales of the presence of these man-made obstacles. Another alarm type, under development, has been distributed to commercial fisheries operating in Queensland waters to reduce the risk of humpback Whale entanglement in commercial gear. A standard acoustic warning protocol is tinder development for humpback whales, integrating specific alarm source levels, acoustic propagation and ambient noise levels. How relevant to humpback whales this standard will be is not dear, however U should provide a benchmark against which whale entanglement, or lack of it, may he compared.