Designate a Marine Protected Area and prohibit commercial fishing
Overall effectiveness category Unknown effectiveness (limited evidence)
Number of studies: 2
Background information and definitions
Commercial fishing can impact subtidal benthic invertebrates through species removal or habitat damage from fishing gear entering in contact with the seabed (Collie et al. 2000). Specific areas can be designated as protected, and specific management measures taken to control for impactful activities, such as commercial fishing (Villamor & Becerro 2012). Inside protected areas where commercial fishing is prohibited, the threat from commercial fishing to subtidal benthic invertebrates is removed, and previously impacted populations are, in theory, able to recover over time (Ley‐Cooper et al. 2014). However, species and populations are still subjected to the effects of other fishing activities that are allowed (for instance recreational fishing).
When this intervention occurred outside of a marine protected area, evidence has been summarised under “Threat: Biological resource use – Cease or prohibit commercial fishing”. Evidence for interventions related to recreational fishing is summarised under “Threat: Human intrusions and disturbances”. Evidence for other interventions related to fisheries restrictions within marine protected areas is summarised under “Habitat protection”.
Collie J.S., Hall S.J., Kaiser M.J. & Poiner I.R. (2000) A quantitative analysis of fishing impacts on shelf‐sea benthos. Journal of Animal Ecology, 69, 785–798.
Ley‐Cooper K., De Lestang S., Phillips B.F. & Lozano‐Álvarez E. (2014) An unfished area enhances a spiny lobster, Panulirus argus, fishery: implications for management and conservation within a Biosphere Reserve in the Mexican Caribbean. Fisheries Management and Ecology, 21, 264–274.
Villamor A. & Becerro M.A. (2012) Species, trophic, and functional diversity in marine protected and non-protected areas. Journal of Sea Research, 73, 109–116.
Supporting evidence from individual studies
A replicated, before-and-after study in 1977–2005 of nine rocky seabed sites in the South Pacific Ocean, north-eastern New Zealand (Shears et al. 2006a) found that over the 12 years after implementing a marine park prohibiting commercial fishing but allowing the recreational harvest of spiny lobsters Jasus edwardsii, abundance and biomass of lobsters inside the park did not increase. Average lobster abundance was statistically similar before (7–47 lobsters/transect) and 12 years after implementation (4–9). Average biomass of legal-size lobsters (>95 mm carapace length) was similar before (1–3 kg/transect) and after implementation (0–1). Mimiwhangata Marine Park was established in 1984 (implemented 1993). Between 1977 and 2005, nine sites inside the park were surveyed annually. Divers counted all lobsters and visually estimated the size and weight of legal-size lobsters along one 50 x 10 m transect/site.
A replicated, site comparison study in 2003 of 17 rocky seabed sites in the South Pacific Ocean, north-eastern New Zealand (Shears et al. 2006b) found that 10 years after implementing a marine park prohibiting commercial fishing but allowing the recreational harvest of spiny lobsters Jasus edwardsii, abundance and size of lobsters were not higher inside the park compared to outside where fishing occurred. Lobster abundance was not different inside (24 lobsters/transect, of which 8 were legal-sized) and outside the park (28 lobsters/transect, of which 6 were legal-sized). The carapace length of lobsters was not different inside (82 mm) and outside (88 mm) the park. Mimiwhangata Marine Park was established in 1984 (implemented 1993). In 2003, nine sites inside the park and eight fully-fished sites outside were surveyed. Divers counted and visually estimated the size of lobsters along three 50 x 10 m transects/site.Study and other actions tested
A site comparison study in 2011–2012 of two areas in the Caribbean Sea, Mexico (Ley‐Cooper et al. 2014) found that Carribbean spiny lobsters Panulirus argus grew larger in an area where commercial fishing was banned compared to a fished area, and that a high proportion of the lobster population in the unfished area stayed there over the duration of the study and thus remained protected. Lobster sizes were greater in the unfished area (94 mm) compared to the fished area (73 mm). In the unfished area, this corresponded to 99% of lobsters being bigger than the minimum legal catch size (74.5 mm), while in the fished area it corresponded to only 25%. In addition, an estimated 20% of the lobster population occurring in the unfished area moved to the fished area over the duration of the study, thus 80% remained protected inside the unfished area. The study was carried out in a Biosphere Reserve (year of designation unspecified) which restricted commercial fishing to shallow depths (<20 m) and banned it where depths exceed 20 m (see paper for details). In August–September 2011, lobsters were hand-caught from the unfished area, tagged, sized (carapace length) and released in the unfished area (379 in total). During the 2011/2012 fishing season in the fished area, all lobsters caught by fishermen were sized, and tagged lobsters recorded. A tag-recapture model based on the number of recaptured tagged lobsters (20 in total) was used to estimate the percentage of the lobster population moving from the protected to the fished area.Study and other actions tested