Assessing coral reef fish population and community changes in response to marine reserves in the Dry Tortugas, Florida, USA

Published source details Ault J.S., Smith S.G., Bohnsack J.A., Luo J., Zurcher N., McClellan D.B., Ziegler T.A., Hallac D.E., Patterson M., Feeley M.W., Ruttenberg B.I., Hunt J., Kimball D. & Causey B. (2013) Assessing coral reef fish population and community changes in response to marine reserves in the Dry Tortugas, Florida, USA. Fisheries Research, 144, 28-37.
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This study is summarised as evidence for the following.

	Action	Category
	Cease or prohibit all commercial fishing Action Link
	Cease or prohibit all types of fishing in a marine protected area Action Link

Cease or prohibit all commercial fishing

A before-and-after, site comparison study in 1999–2011 of a large managed reef area in the Gulf of Mexico, Florida, USA (5) found that fish densities in an area of a marine reserve where commercial fishing had been prohibited for over 30 years, varied with level of commercial exploitation over a ten-year period and immediately following conversion of half of the area to no-take (no fishing), and abundances of five of five commercially exploited species were greater compared to adjacent openly fished areas. For five of five commercially targeted fish, increases in density were detected in 2–7 surveys (out of 7) in the non-commercially fished area and there were no decreases, while in the fished areas an increase in density was detected in one of four surveys and density decreased in two to three. For 11 non-target fish species, five species collected for the aquaria trade and two protected groupers Epinephelus spp., changes in density fluctuated between years in both areas (see paper for species individual data). In addition, adult percentage abundances of the five commercial species increased overall in the non-commercially fished area from baseline levels (1999–2000) of 49–71% to 54–87% in 2008–2010 (a year after half of the area was made no-take), while abundances in openly fished areas showed overall decreases (1999–2000: 9–27%, 2008–2010: 1–23%). Fish were monitored in two areas of the Dry Tortugas region with different levels of management protection: Dry Tortugas National Park (~320 km², fishing prohibited except hook and line angling since the 1960s; half of the area designated as no-take in 2007) and an area with open access to commercial and recreational fishing. Both areas were adjacent to other no-take reserves. Baseline fish surveys were done in 1999–2000 (two surveys) and monitoring surveys every one or two years from 2002–2011 (seven surveys in non-commercially fished and four in fished areas). A total of 8,106 diver visual counts were done in a two-stage stratified random sampling design. Numbers of reef fish were recorded in randomly selected circular plots 15 m in diameter.

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

A replicated, before-and-after, site comparison study in 1999–2011 at four coral reef sites in the Gulf of Mexico, off Florida Keys, USA (Ault et al. 2013) found that in marine reserve areas where all fishing was prohibited for up to 10 years, and in areas where only recreational fishing is permitted, there were increases in the density of commercial fish species in the 10 years following implementation and compared to openly fished areas, and changes in fish densities of non-target and other exploited fish species varied. For five fishery exploited species, the total number of increases in density detected in surveys was higher overall in no-take and recreationally fished areas compared to openly fished areas (no-take: 3, recreational: 16, fished: 1), and decreases were only detected in the openly fished areas (no-take: 0, recreational: 0, fished: 5). For non-target species (increase, no-take: 9, recreational: 20, fished: 12; decrease, no-take: 9, recreational: 12, fished: 3) and species collected for the aquaria trade (increase, no-take: 0, recreational: 7, fished: 1; decrease, no-take: 9, recreational: 7, fished: 3), changes in density fluctuated between years (see paper for species individual data). Fish were surveyed over 326 km² at four sites with three different levels of resource management protection; Tortugas North and South Ecological Reserves (no-take, since 2001), Dry Tortugas National Park (part no-take, since 2007 and part recreational angling only, since 1960s in all areas). Baseline fish surveys were done in 1999–2000 before the no-take areas were implemented and from 2002–2011. Diver visual surveys were done in a two-stage stratified random sampling design. Numbers of reef fish were recorded in randomly selected circular plots 15 m in diameter.

(Summarised by: Khatija Alliji)