Recovery of a Temperate Reef Assemblage in a Marine Protected Area following the Exclusion of Towed Demersal Fishing

Abstract

Marine Protected Areas MPA have been widely used over the last 2 decades to address human impacts on marine habitats within an ecosystem management context. Few studies have quantified recovery of temperate rocky reef communities following the cessation of scallop dredging or demersal trawling. This is critical information for the future management of these habitats to contribute towards conservation and fisheries targets.The Lyme Bay MPA, in south west UK, has excluded towed demersal fishing gear from 206 km2 of sensitive reef habitat using a Statutory Instrument since July 2008.To assess benthic recovery in this MPA we used a flying video array to survey macro epi-benthos annually from 2008 to 2011. 4 treatments (the New Closure, previously voluntarily Closed Controls and Near or Far Open to fishing Controls) were sampled to test a recovery hypothesis that was defined as ‘the New Closure becoming more similar to the Closed Controls and less similar to the Open Controls’.Following the cessation of towed demersal fishing, within three years positive responses were observed for species richness, total abundance, assemblage composition and seven of 13 indicator taxa. Definitive evidence of recovery was noted for species richness and three of the indicator taxa (Pentapora fascialis, Phallusia mammillata and Pecten maximus).While it is hoped that MPAs, which exclude anthropogenic disturbance, will allow functional restoration of goods and services provided by benthic communities, it is an unknown for temperate reef systems. Establishing the likely timescales for restoration is key to future marine management. We demonstrate the early stages of successful recruitment and link these to the potential wider ecosystem benefits including those to commercial fisheries.

The Ecological and Evolutionary Consequences of Marine Reserves

“…Reserves can reduce mortality of nontarget species if they are caught as bycatch (Murawski et al 2000). In addition, in areas fished with habitat-destructive fishing gear, reserves can lead to increases in habitat-forming organisms that benefit the entire community (Lindholm et al 2004), which can lead to particularly strong responses in diversity (Sheehan et al 2013). More generally, however, lack of exploitation can explain why some species do not respond to reserve establishment (Molloy et al 2009).…”

What is the impact on fish recruitment of anthropogenic physical and structural habitat change in shallow nearshore areas in temperate systems? A systematic review protocol

“…Today, controversies remain as to what the primary causes of larval and juvenile fish declines are; whether anthropogenic alteration or loss of nursery coastal habitats are responsible for the declines; to what extent various habitat restoration approaches are effective; and what, if anything, can be done to reverse the declines of fish stocks [5,12]. However, recently, researchers have focused their attention on the links between anthropogenic pressures and fish recruitment success, and the accumulation of new data (see for example: [31][32][33][34][35]) suggests that a systematic review on the topic could find relevant evidence to support management actions directed towards maintaining the function of shallow nearshore and coastal areas and the conservation or restoration of fish populations.…”

Patterns of benthic mega-invertebrate habitat associations in the Pacific Northwest continental shelf waters

“…Repeated contacts of bottom-trawls on the reefs have damaged or even eradicated slow-growing structure-forming sessile invertebrates and the motile species they attract (Watling and Norse 1998;Kaiser et al 2006;Sheehan et al 2013). Nevertheless, because of the decline in rockfish stocks along the PNW coast at the end of the twentieth century (see review in NRC 2002), the Pacific Fishery Management Council established in the early 2000's new regulations leading to a drastic decrease of the fishing pressure on part of the rocky reefs particularly on the outer continental shelf (Hannah 2003;Bellman et al 2005;Bellman and Heppell 2007).…”

“…Other human uses of the oceans like aquaculture, mining or tourism activities threaten continental shelf ecosystems (Rossi 2013) and their effects, both direct and indirect, can be synergistic (Jackson et al 2001;Kaplan et al 2013). Human use changes such as marine protected areas (MPAs) and marine renewable energy developments (MREs), like wave energy or offshore wind farms, both may have some benefits for ecosystems by closing some areas to fisheries (Sheehan et al 2013). However, potential negative effects of MREs arise from introducing hard structure to sedimentary seafloor habitats as well as changing current and sediment flow patterns.…”

“…One of the major threats of seafloor exploitation to continental shelf ecosystems is a reduction of habitat complexity and heterogeneity by damage to or smothering of slowgrowing structure-building organisms like sponges or gorgonians, which may create biogenic habitat (Watling and Norse 1998;Kaiser et al 2006;Sheehan et al 2013) as well as damage to or sedimentation of rocky outcrop or reefs themselves. Habitat heterogeneity can be a major driver of variability in the abundance and diversity of marine species (Benedetti-Cecchi and Cinelli 1995;García-Charton et al 2004), supporting global species diversity by increasing niche availability and community complexity and facilitating the formation of distinct species assemblages (Cerame-Vivas and Gray 1966;García-Charton et al 2004;McClain and Barry 2010).…”