Analyses of CPUE from the four islands of the Tristan da Cunha group to examine effects of trip length and period of rest between trips on CPUE performance

Cursory examination of CPUE data as well as anecdotal evidence from skippers and fishermen have suggested that two important mechanisms may be at play concerning the behavior of CPUE values over time. Firstly, it has been suggested that CPUE falls off fairly rapidly during a single fishing trip. Secondly, by leaving the fishing ground to “rest” for a period improves the catch rates on return. The analysis presented here explores these two possibilities.