Assessing the effectiveness of a long‐standing rocky intertidal protected area and its contribution to the regional conservation of species, habitats and assemblages

Abstract

1. The acceptance of reserves as a useful management strategy relies on evidence of their effectiveness in preserving stocks of harvested species and conserving biodiversity. A history of ad hoc decisions in terrestrial and marine protected area planning has meant that many of these areas are contributing inefficiently to conservation goals. The conservation value of existing protected areas should be assessed when planning the placement of additional areas in a reserve network.2. This study tested (1) the effectiveness of protection for intertidal molluscs of a marine reserve (Bouddi Marine Extension, NSW, Australia) established in 1971, and (2) the contribution of the protected area to the conservation of regional species, assemblages, and habitats.3. The shell length and population density of one harvested (Cellana tramoserica), and three non-harvested species (Bembicium nanum, Morula marginalba, Nerita atramentosa) of intertidal molluscs were examined in the protected area and two reference locations over two seasons.4. The heavily collected limpet C. tramoserica was significantly larger in the protected area and was the only species to exhibit a significant difference. No species significantly differed in population density between the protected area and reference locations. 5. Temporally replicated surveys of macro-molluscs at 21 locations over 75 km of coastline identified that the existing protected area included 50% of species, two of five assemblage types and 19 of 20 intertidal rocky shore habitats surveyed in the study region. Reservation of a further three rocky reefs would protect a large proportion of species (71%), a representative of each assemblage and all habitat types.6. Despite originally being selected in the absence of information on regional biodiversity, the protected area is today an effective starting point for expansion to a regional network of intertidal protected areas.

Assessing the effects of no-take zones in a marine protected area spanning two ecoregions and rock substrate types

“…The selection of larger individuals of C. granatina by shellfish gatherers upholds our first hypothesis to this effect and supports other findings that shellfish gatherers target large individuals (Durań et al, 1987;Lasiak, 1991a;Lasiak, 1992;Jimenez et al, 2011;Alexander and Gladstone, 2012). This usually leads to reductions in the mean sizes of the individuals in the natural populations (Eekhout et al, 1992;Jimenez et al, 2011), with profound effects on reproductive output (Branch, 1975;Branch and Odendaal, 2003).…”

“…Exclusion of shellfish gatherers from MPAs often leads to greater densities of commonly harvested species inside no-take areas relative to harvested areas (Moreno et al, 1984;Hockey and Bosman, 1986;Moreno et al, 1986;Hockey et al, 1988;Edgar and Barrett, 1999;Alexander and Gladstone, 2012;Bednar and Trulio, 2017). For example, higher densities of the limpet Cellana tramoserica were found in the Bouddi National Park Marine Extension relative to unprotected shores (Alexander and…”

New opportunities for conservation of a threatened biogenic habitat: a worldwide assessment of knowledge on bivalve-reef representation in marine and coastal Ramsar Sites

“…Although recognition of their sensitivity and the need for exploitation to be sustainable has led to the protection of bivalves and other molluscs in some places (e.g. Bertocci et al 2012;Alexander and Gladstone 2013), globally they remain at a significant risk (Beck et al 2011).…”

Endemic fish species structuring oceanic intertidal reef assemblages

“…The structural complexity, partial isolation and species richness of tidepools can be used as proxies to assess a variety of ecological and anthropic impacts scenarios to gain a better understanding of marine systems changes over time 10 , 23 , 24 . Intertidal environments are particularly good models because of the possibility to measure community metrics (i.e., density, number of taxa or biomass) using actual tridimensional data (volume).…”