The effectiveness of escape gaps in beehive rock lobster pots at Cape Campbell, New Zealand.

This copy lacks figures

The objective of this study was to compare for the beehive type pot the efficiency of escape gaps on catches of legal and below legal sized rock lobsters (Jasus edwardsii Hutton) or various soak times (pot fishing period). Soak times compared were less than 12 hours, 12-24 hours, 24-36 hours, and all soak times combined. A total of 271 pots with escape gaps were compared with 336 without gaps at Cape Campbell, New Zealand, during monthly sampling (except March - May) from December 1975 to November 1976. Escape gaps did not significantly effect commercial catches nor catches of undersize rock lobsters when the soak time was less than 12 hours. Escape gaps did significantly reduce the number of undersize rock lobsters caught in pots that had a soak time of 12-24 hours and 24-36 hours. Escape gaps did significantly reduce the number of undersize rock lobsters caught in pots that had a soak time of 12-24 lours and 24-36 hours. May be during the first 12 hours the rock lobsters are entering the pots and remaining to feed on the bait. However after 12 hours the rock lobsters may finish feeding and the escape gap provides the means of escape for below legal sized animals. Catch rates of legal sized animals caught in both types of pots improved with increasing soak times. The below legal sized catches of escape gap pots that fished for 12-24 ours showed an almost fourfold reduction in numbers when compared to pots without gaps. Octopus (Octopus maorum) predation was greater in pots without escape gaps. The number of other fish caught in both was small with greater numbers being caught in escape gap pots.

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