Cease or prohibit customary fishing (indigenous fishing for cultural and community needs)

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

Study locations

Key messages

  • One study examined the effects of ceasing or prohibiting customary fishing in an area, on marine fish populations. The study was in the Bismark Sea (Papua New Guinea).



  • Abundance (1 study): One site comparison study in the Bismark Sea found a higher abundance of only one of seven fish species in an area closed to customary fishing for eight years, compared to an area open to customary fishing.


  • Behaviour change (1 study): One site comparison study in the Bismark Sea found that in an area closed to customary fishing for eight years, six of seven fish species had a lower flight response distance compared to an area open to customary fishing, making them more vulnerable to capture with spear guns.

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 site comparison study in 2008 at two reefs in the Bismark Sea, Papua New Guinea (Feary et al. 2010) found that permanent closure of areas regulated by traditional fishing rights (customary fishing) resulted in greater abundance of only one of seven species compared to fished areas after eight years, and the flight response of six species decreased. Striated surgeonfish Ctenochaetus striatus were more abundant inside closed areas compared to fished areas (closed: 47, open: 25 fish/1,000 m2), but abundances of the other six species (orange-lined triggerfish Balistapus undulatus, Bleeker’s parrotfish Chlorurus bleekeri, daisy parrotfish Chlorurus sordidus, yellowbarred parrotfish Scarus dimidiatus, dusky parrotfish Scarus niger, and humpback red snapper Lutjanus gibbus) were similar (inside: 1–31, outside: 1–14 fish/1,000 m2). In addition, flight response of all but one species (humpback red snapper) inside the closure area was shorter (closed: 131–365 cm, open: 207–551 cm) making them more vulnerable to capture by spear guns (range 1.3 to 3.1 m). Fish were surveyed on reefs off Karkar Island inside and outside one site (0.5 km2) that at the time of the study had been closed to customary fishing (using spear guns and hand lines as primary gear types) for 8 years, with the exception of a 2-week period during which it was opened to fishing for a ceremonial feast (details of when sampling took place were not reported). The community maintains a customary system of reef management where a portion of the reefs is closed for several years when the clan chiefs decide fish are staying out of the range of spear guns. Sampled reefs outside the closure area had not been closed to fishing. At five locations at each site, two, 50 × 5 m belt transects at 2–4 and 6–8 m depths were surveyed by underwater visual census. Fish flight distance was measured by placing weighted markers on a measuring tape at the start position of the fish and the final position after disturbance.

    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

All the journals searched for all synopses

Marine Fish Conservation

This Action forms part of the Action Synopsis:

Marine Fish Conservation
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