Gill net mesh selectivities for gummy shark, Mustelus antarcticus Günther, taken in south-eastern Australian Waters

摘要: Experiments designed to estimate length-specific selectivities for gill nets used catch gummy shark, M. antarcticus, were carried out in south-eastern Australian waters between 1973 and 1976. Eight used, with mesh sizes ranging from 5.08 22.78 cm (2-9 in.) steps of 2.54 (1 in.). Existing methods estimating are reviewed, an alternative method, which overcomes some problems the existing methods, is described. In this assumed selectivity function fitted directly data a number different sizes, parameters being estimated simultaneously across length-classes. The new method shark data, on assumption that takes shape gamma distribution. Data 2- 3-in. did not satisfy assumptions procedure, but estimates successfully obtained 4-9-in. nets.