Cease or prohibit all fishing activity in a marine protected area with limited exceptions

How is the evidence assessed?
  • Effectiveness
    not assessed
  • Certainty
    not assessed
  • Harms
    not assessed

Study locations

Key messages

  • Four studies examined the effects of ceasing or prohibiting all fishing activity in a marine protected area with limited exceptions on marine fish populations. One study was in each of the Pacific Ocean (USA), the Caribbean Sea (US Virgin Islands), the Great Barrier Reef (Australia) and the Skagerrak (Norway).


  • Richness/diversity (1 study): One site comparison study in the Caribbean Sea found that in marine protected areas closed to all fishing with limited exceptions for up to seven years, there was lower total fish species richness compared to unprotected areas.


  • Abundance (2 studies): One replicated, site comparison study in the Pacific Ocean found that abundance of copper rockfish, quillback rockfish, china rockfish and lingcod was similar between non-voluntary and voluntary ‘no-take’ reserve sites where all fishing with limited exceptions had been prohibited for one to eight years, and sites open to fishing. One site comparison study in the Caribbean Sea found that restricting all fishing activity except for bait fishing in marine protected areas for seven years resulted in similar total fish biomass and lower total fish density, compared to unprotected areas.
  • Survival (1 study): One replicated, controlled, before-and-after study in the Skagerrak found that cod survival increased inside a marine protected area in the eight years after almost all fishing was prohibited, compared to outside areas fished with a wider range of gear types.


  • Use (1 study): One replicated study in the Great Barrier Reef found that immature pigeye sharks and adult spottail sharks were detected frequently and over long time periods inside marine protected areas five years after prohibiting almost all fishing except restricted line fishing and bait netting, thus reducing the overall likelihood of fishing mortality.

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A replicated, site comparison study in 1998 of eight rocky and sandy sites in the San Juan Archipelago, northwest Pacific Ocean, USA (Tuya et al. 2000) found no differences in the abundances of copper rockfish Sebastes caurinus, quillback rockfish Sebastes maliger, China rockfish Sebastes nebulosus and lingcod Ophiodon elongatus between voluntary no-take sites (no collection of finfish except for salmon) protected for one year, no-take sites (all collection of marine organisms prohibited except for approved scientific research) protected for eight years, and nearby sites open to fishing. Results were reported only as statistical results (ordination analyses). The authors suggested the lack of increase in fish abundance inside protected compared to non-protected areas was likely due to a lack of compliance and enforcement of the restrictions. In July 1998, two marine protected areas (designated 1997 as voluntary no-take zones where no finfish except salmon could be collected – no gears specified), three research marine reserves (established 1990, extractive activities prohibited except for research, sea urchin fishery closed since late 1970s), and three unprotected openly fished areas were surveyed. Two divers identified and counted fish along 300 m2 transects on reef slopes up to 20 m deep (4 transects/site).

    Study and other actions tested
  2. A site comparison study in 2003–2008 of two reef areas in the Caribbean Sea, US Virgin Islands (Monaco et al. 2009) found that prohibiting almost all fishing except for bait within a marine protected area resulted in lower fish species richness and density and similar fish biomass compared to adjacent unprotected areas in the seven years after protection. Species richness and fish density was lower inside the protected area than outside (species richness: 24 vs 27 species/100 m2; density 229 vs 294 fish/100 m2) and biomass was similar (inside: 7,900, outside: 8,800 g/100 m2). The Virgin Islands Coral Reef National Monument was established in 2001 to extend the existing Virgin Islands National Park. In the study area, all extractive uses and boat anchoring were prohibited, except for a small area where bait fishing was permitted (no species or gears specified). Annually, in July 2003–2008, protected areas (18–20 sites/year) and fished areas (15–18 sites/year) were surveyed. Divers recorded fish number, length and species along 25 × 4 m belt transects. Biomass was estimated using average length for each size class.

    Study and other actions tested
  3. A replicated study in 2009–2010 of two shallow coastal areas in the Great Barrier Reef, Coral Sea, Australia (Knip et al. 2012) found that individuals of two shark species displayed frequent and long-term use of marine protected areas prohibiting all fishing (except restricted line fishing and bait netting) for five years, and thus were protected from fishing for a proportion of time. Immature pigeye Carcharhinus amboinensis and adult spottail Carcharhinus sorrah were detected inside protected areas an average of 23% (range 2–67%) and 32% (range 0–67%) of time respectively, and for 4–676 days (average 190 days) and 28–566 days (average 281 days). In addition, the amount of time spent inside protected areas was significantly different between sexes for spottail, but not pigeye, with female spottail spending more time (38%) than males (21%). All the tracked sharks left the protected areas during monitoring, on average 0.9 times/day for pigeye and 1.7 times/day for spottail. Sharks were monitored in two marine protected areas in Cleveland Bay (140 km2) off the wider Great Barrier Reef Marine Park (rezoned in 2003) in which trawling and netting (bait netting excluded) are prohibited and line fishing is limited to one line per person and one hook per line. Sharks are not targeted by the permitted fisheries and 95% are released alive if captured. From 2009 to 2010, tracking data was collected from 37 sub-adult pigeye and 20 adult spottail fitted with acoustic transmitters by 55 underwater receivers deployed inside the two protected areas.

    Study and other actions tested
  4. A replicated, controlled, before-and-after study in 2005–2013 of three seabed areas in the Skagerrak, Norway (Fernández-Chacón et al. 2015) found that in a marine protected area prohibiting almost all fishing, except for commercial hook and line fishing of cod Gadus morhua and research sampling, cod survival increased over eight years, compared to outside areas where a wider range of fishing gear types were allowed. Overall average survival probability of cod inside the protected area increased after implementation (after: 0.2–0.4, before: 0.1–0.2) and in comparison with areas outside the protected area (after: 0.2, before: 0.2). Sampling was done in April–July 2005–2013. Cod were captured inside the protected area and at two unprotected sites with fyke nets and tagged and released at the capture location. Data on 10,764 recaptures of tagged fish were used: 1,454 tagged within the protected area and 9,310 tagged in other areas along the Skagerrak coast. Survival was estimated using a model, described in the original paper. The protected area (Flødevigen, 1 km2) was implemented in September 2006 and allowed a hook and line fishery and research sampling. At unprotected areas, hook and line, gillnets, fyke nets and other fishing gear types were allowed, but not bottom trawling within 12 nautical miles from the coast, with an exception for small scale coastal trawling for shrimp Pandalus borealis.

    Study and other actions tested
Please cite as:

Taylor, N., Clarke, L.J., Alliji, K., Barrett, C., McIntyre, R., Smith, R.K., and Sutherland, W.J. (2021) Marine Fish Conservation: Global Evidence for the Effects of Selected Interventions. Synopses of Conservation Evidence Series. University of Cambridge, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

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Marine Fish Conservation

This Action forms part of the Action Synopsis:

Marine Fish Conservation
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