WWF Cover photo - Soufriere Marine Management Association ...

Lobster densities inside reserves increased by nearly 4% per year in shallow sites (less than 10m) and by 9.5% insites deeper than 10m. Mean carapace length of lobsters increased by 1.14mm per year of protection, and lobsterbiomass was estimated to have expanded by 5.4% per year of protection in shallow sites and by 10.9% per yearin deep sites. Estimated egg production increased by 4.8% (shallow) and 9.1% (deep) per year of protection.In 1985/6 lobster fishers began setting their pots around the boundary of the Leigh reserve. Fishers reported verylarge catches with large male lobsters filling pots (Kelly et al. 1997, in Walls 1998). More recently, Kelly et al.(2002) looked at the value of the spillover fishery around the Leigh Marine Reserve. They compared catch perunit effort at the reserve boundary with a fishing site 0.3-2km from the reserve and another site 22-30km fromthe reserve. They found no significant difference in CPUE (in kg per trap haul) among the sites. However,catches from the reserve boundary could only be made in the deeper offshore habitat as fishers could not use theinshore reefs favoured by lobsters at certain times. Catches from the reserve boundary contained fewer but largerlobsters, and were more variable than those from the other two sites. However, the amount of money made pertrap haul was similar at each site because the occurrence of empty pots was offset by pots containing largenumbers of lobsters. For instance, in 1995 nearly 21.6% of revenue earned by the study fishers came from just4.4% of trap hauls. High variability in catches is not something that is usually predicted for reserves and in thiscase is a consequence of the aggregation behaviour of lobsters near the reserve. Because of the seasonal natureof offshore aggregation, high catch rates were only possible during 7-8 months of the year and outside thesemonths catches were likely to be low.Jasus edwardsii supports one of New Zealand’s most valuable inshore fisheries and is managed though a quotascheme that is perceived by fishers to work fairly well. The lobster fishing industry therefore opposes marinereserves, arguing that the quota system is a conservation tool and that marine reserves are not an effectivemanagement tool (S. Kelly pers. comm.). No detailed information was available on how the fishing communityin general responded to the presence of reserves. However, the study fishers from whom Kelly et al. (2002)collected the CPUE data, responded to the loss of inshore reef sites and reduction of fishing area at the marinereserve by increasing the density of traps set around the reserve boundary. Evidence from New Zealand’sreserves suggest that while they are presently small and acting principally as conservation tools, they could playa useful role in supporting other lobster fishery management measures.Effects on commercial and recreational fishCole et al. (1990) studied densities of a variety of fish species in the Leigh Marine Reserve using underwatervisual census in 1982 and found that only one species, the red moki (Cheilodactylus spectabilis) increased inabundance over the initial 6 years of management. Abundance of five other species, the snapper (Pagrusauratus), goatfish (Upeneichthys lineatus), spotty (Notolabrus celidotus), blue cod (Parapercis colias) andleatherjacket (Parika scaber) did not change significantly in these initial years. A subsequent survey in 1988showed increasing abundance of snapper, blue cod, red moki and rock lobsters, but no trend in the abundance ofsea urchin (Evechinus chloroticus).Babcock et al. (1999) studied the most common demersal predatory fish, the snapper (Pagrus auratus), in theLeigh Marine Reserve and Tawharanui Marine Park and found that adults were 5.8 and 8.7 times more abundantinside the reserves than in adjacent fished areas. Individuals were also significantly larger with mean lengths of316mm inside protected areas compared to 186mm in fished areas.Babcock et al. (1999) found significant differences in abundance of non-target species such as sea urchins(Evechinus chloroticus) which declined to less than a third of their former abundance in one of the marinereserves over 20 years of protection. They also found that kelp beds were more extensive in one of the reserves.This suggests fishing pressure has changed not only the mean size and abundance of target species, but also thewider ecosystem. Snappers and lobster prey on urchins which in turn graze on kelp. In a study using tetheringexperiments, Shears and Babcock (2002) found that predation of sea urchins was 7 times higher inside the LeighMarine Reserve and the Tawharanui Marine Park than in unprotected areas. Growing snapper and lobsterpopulations in reserves have helped reduce urchin densities and facilitated an increase in algal cover. Urchinbarrens covered 40% of available reef in unprotected areas but only 14% in reserves. Babcock et al. (1999)estimate that primary productivity from macroalgae like kelp has increased by 58% from what is was before theLeigh Marine Reserve was established. Benthic primary productivity was also found to be much lower outsidethe reserves than before intensive fishing began. Overall this study reveals some of the complex interactions thatinfluence recovery of protected ecosystems from previously high levels of fishing.Willis et al. (in review) studied density and size of snapper inside and outside three marine reserves in northernNew Zealand: Leigh Marine Reserve, Hahai Marine Reserve and Tawharanui Marine Park. Snapper is the most43