Top-down trophic shifts in Florida Keys patch reef marine protected areas

  • Published source details Kramer K.L. & Heck Jr. K.L. (2007) Top-down trophic shifts in Florida Keys patch reef marine protected areas. Marine Ecology Progress Series, 349, 111-123.


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

    A replicated, site comparison study in 2004 of five coral reef sites in the Florida Keys, Atlantic Ocean, USA (Kramer & Heck 2007) found that prohibiting all fishing within marine protected areas (no-take) for 6 years resulted in higher biomass, body length and abundance of some reef fish species and sizes, but not others, compared to unprotected fished reefs. The average biomass of one of two species of groupers Serranidae spp. and one of three snappers Lutjanidae spp. was higher inside (grouper: 1,190; snapper: 910 g/125 m2) than outside no-take areas (grouper: 130; snapper: 30 g/125 m2), but was similar for the others (inside: 590–2,400, outside: 100–2,500 g/125 m2; see paper for individual data). Average body lengths of two of the three snappers were greater in no-take areas, while no differences were found for the other snapper and the only grouper for which there was sufficient data (data reported as statistical results). For three groups of herbivorous fish (see original paper for species), adult sizes of two were more abundant in no-take areas (inside: 0.30–0.98, outside: 0.13–0.74 m2) and abundances of immature sizes were lower (inside: 0.04–0.60; outside: 0.12–1.50 fish/m2), while abundance of the other species was similar for both adults and immature fish (inside: 0.05–0.30, outside: 0.03–0.10 fish/m2). Patch reefs were sampled in three Special Protected Areas (average 0.5 km2, established 1997, no resource extraction) and at two fished reefs (1 to 3 km apart). Predatory and herbivorous fish were recorded along three 25 × 5 m and 20 × 1 m belt transects, respectively. Predatory fish were surveyed on 5-6 days in June-September 2004 and herbivorous fish on 7–9 days in June-September 2003 and 2004.

    (Summarised by: Leo Clarke)

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