Impact of conservation areas on trophic interactions between apex predators and herbivores on coral reefs

Published source details Rizzari J.R., Bergseth B.J. & Frisch A.J. (2015) Impact of conservation areas on trophic interactions between apex predators and herbivores on coral reefs. Conservation Biology, 29, 418-429.
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This study is summarised as evidence for the following.

	Action	Category
	Control human activity in a marine protected area with a zonation system of restrictions Action Link
	Cease or prohibit all types of fishing in a marine protected area Action Link

Control human activity in a marine protected area with a zonation system of restrictions

A site comparison study in 2011–2013 of 18 coral reef sites in the Great Barrier Reef, Coral Sea, Australia (Rizzari et al. 2015) found that in a marine protected area where human activity has been controlled by zones for 10-20 years, two of six different groups of fish were more abundant and two had a larger size and biomass in no-entry zones than no-take and fished zones. Densities of apex predators and browser herbivores were higher in the no-take zone compared to both the no-take and fished zones but there were no differences between areas for targeted and non-targeted medium-sized predators and two other groups of herbivorous fish (data reported graphically and as statistical results). Fish size and biomass differed between areas only for the targeted and non-targeted predator groups and were higher in the no-entry zone than the other zones (data reported as statistical results). In addition, the differences in the predator groups due to protection level were not found to influence the density, size or biomass of the herbivorous fish groups. Reefs in three management zones within the Great Barrier Reef Marine Park were surveyed from October-April 2011–2013: no-entry (protection >20 years), no-take (protected 10–20 years where fishing is prohibited but non-extractive activities like diving are allowed), and fished areas. Fish were categorized into six groups according to food chain position and exploitation status (see original paper for details). At each reef (six/zone), apex predators were surveyed 2-6 times using 45-minute timed swims (20 m wide transect) and medium-sized predators and herbivores >10 cm total length using 10-16 transects (10 × 50 m).

(Summarised by: Khatija Alliji)
Cease or prohibit all types of fishing in a marine protected area

A site comparison study in 2011–2013 of 18 coral reef sites on the Great Barrier Reef in the Coral Sea, Australia (Rizzari et al. 2015) found that in a marine protected area where human activity was controlled by zones, of six different fish trophic groups, two were more abundant and two had a larger size and biomass in no-entry zones than no-take and fished zones, after 10 to >20 years of protection. Densities of apex predators and browser herbivores were higher in the no-take zone compared to both the no-take and fished zones but there were no differences between areas for targeted and non-targeted medium-sized predators and two other groups of herbivorous fish (data reported graphically and as statistical results). Fish size and biomass differed between areas only for the targeted and non-targeted predator groups and were higher in the no-entry zone than the other zones (data reported as statistical results). In addition, the differences in the predator groups due to protection level were not found to influence the density, size or biomass of the herbivorous fish groups. Reefs in three management zones within the Great Barrier Reef Marine Park were surveyed from October-April 2011–2013: no-entry (protection >20 years), no-take (protected 10–20 years where fishing is prohibited but non-extractive activities like diving are allowed), and fished areas. Fish were categorized into six groups according to food chain position and exploitation status (see original paper for details). At each reef (six per zone), apex predators were surveyed two to six times using 45-minute timed swims (20 m wide transect) and medium-sized predators and herbivores >10 cm total length using 10 to 16 transects (10 × 50 m).

(Summarised by: Khatija Alliji)