Marine reserves - simple solutions to managing complex fisheries

  • Published source details Roberts C.M. & Polunin N.V.C. (1993) Marine reserves - simple solutions to managing complex fisheries. Ambio, 22, 363-368.


This study is summarised as evidence for the following.

Action Category

Cease or prohibit all types of fishing in a marine protected area

Action Link
Marine Fish Conservation

Cease or prohibit spearfishing

Action Link
Marine Fish Conservation
  1. Cease or prohibit all types of fishing in a marine protected area

    A review in 1993 of 11 case studies of reef marine reserves across the world prohibiting all types of fishing (Roberts & Polunin 1993) reported that most had increased abundance and size of fish between one and 15 years after protection compared to adjacent fished areas, but there were differences between species or family groups and level of exploitation, and with depth and fishing intensity outside the reserves. Three of four no-take reserves in the Philippines had higher overall fish abundances than fished areas after only one year and in one it had doubled after eight years closure (data not reported). For two reserves in the Caribbean Sea (Belize and Netherland Antilles) established for four years, higher fish densities and average sizes were found for a small number of species, but the biomass of four of five commercially targeted family groups was greater (unfished: 0.1–6.0 kg/count, fished: 0.1–2.0 kg/count), however the effect differed with depth and level of fishing intensity in adjacent fished areas. In a reserve in the Red Sea (Egypt), the effect of prohibiting fishing for 15 years on the abundance and biomass of commercial species was variable and for seven species where they were higher in reserves, average fish weights increased with decreasing fishing intensity (unfished: 42–1,333 g, lightly fished: 41–678 g, fished: 19–447 g). Field studies of reserves were reviewed (search methods not described) and results from sites throughout the tropics discussed.

    (Summarised by: Natasha Taylor)

  2. Cease or prohibit spearfishing

    A review in 1993 of studies of reef marine reserves (Roberts & Polunin 1993) reported that prohibiting spearfishing in two areas in the north Atlantic Ocean/Gulf of Mexico, off the Florida Keys, USA, resulted in increased abundance of targeted snappers and grunts (species not given) two years after closure, and higher densities and larger lengths of several reef fish, including snappers and grunts after 20 years, compared to nearby fished reefs. Two years after spear fishing was prohibited, abundance of snappers and grunts at Looe Key Reef marine sanctuary increased by 93% and 439% respectively, and in addition, several previously absent species also appeared in the prohibited area which were rare in fished areas. Data for the densities and lengths of reef fish in the Key Largo National Marine Sanctuary 20 years after spearfishing was prohibited were not provided. Eleven case studies of reef marine reserves across the world were reviewed (search/selection method not reported); two had evidence for the effects of prohibiting spearfishing.

    (Summarised by: Natasha Taylor)

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