Sawfish captures in the Queensland Shark Control Program, 1962 to 2016

Abstract

Within the Great Barrier Reef World Heritage Area in Queensland, Australia, lack of information on the distribution of sawfishes presents difficulty for informed management of their habitats and populations. This study aims to provide insights into the historical and current distributions through analysis of sawfish by-catch records from the Queensland Shark Control Program (QSCP), which has protected bathers since 1963 by targeting large sharks. Sawfishes have been caught in 8 of the 10 areas where the QSCP has been active. A total of 1450 captures of sawfishes (all 4 species known from Australia) were reported from 1963 to August 2016, with most (>99%) in the 4 most northern areas; Cairns, Townsville, Mackay, and Rockhampton. Sawfishes were mainly captured in gillnets. Most (95.4%) animals were alive when the gear was checked. In Townsville and Rockhampton, standardised sawfish captures have declined over the years. No sawfish captures in QSCP gear have been recorded in 3 areas (Cairns, Townsville, Rockhampton) since gillnets were banned there, but in Mackay, where gillnets are still used, only 4 animals have been caught since 1999. It is recommended that QSCP contractors take more detailed data of future sawfish captures, and that contractors and fishers receive training on releasing sawfishes swiftly and with minimal damage. Moreover, as the use of gillnets in the QSCP has been decreasing over the years, fisheries-independent studies of current sawfish distributions are required.