The model of the krill fishery presented in 1993 (wg-Krill-93/14) refined and applied to both Japanese and Chilean krill fishing fleets in Subarea 48.1. A stochastic element is introduced to account for variability in catch rates. The most successful management regime is found to be one which restricts fishing within 75 km of breeding penguins during January and February. For this regime the model predicts a 90% reduction in overlap with foraging predators, and a 15 to 20% reduction in catch. Closure of Livingston Island for the breeding period resulted in a 60% reduction in overlap with predators and 0 to 15% reduction in catches.
There is no abstract available for this document.
There is no abstract available for this document.
There is no abstract available for this document.
Abstract:
We present data on sexual dimorphism in some morphological measurements (wing length, head length, bill depth and bill length) in the Antarctic Petrel Thalassoica antarctica. Males were on average larger than females for all measurements. Sexual dimorphism was on average largest for bill depths whereas wing lengths discriminated least between the sexes. A discriminant function including bill depth, head length and wing length correctly sexed 92% of the sample. Due to between-measurer variation it is recommended that morphometric measurements obtained by others on sexed birds are compared with ours before proceeding with the use of the discriminant function on unsexed individuals.