Alleviating impacts of anthropogenic activities by traditional conservation measures: can a small reef reserve be sustainedly managed? N. Epstein a,b , M.J.A. Vermeij b,c,d , R.P.M. Bak b,c , B. Rinkevich a, * a Israel Oceanographic and Limnological Research, National Institute of Oceanography, Marine Biology, Tel Shikmona, P.O.B. 8030, Haifa 31080, Israel b Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, P.O.B 94766, 1090 GT, Amsterdam, The Netherlands c Netherlands Institute for Sea Research (NIOZ), P.O.B 59, 1790 AB, Den Burg, Texel, The Netherlands d Caribbean Institute for management and research of Biodiversity, Piscaderabaai z/n, P.O. Box 2090, Willemstad, Curacao, Netherlands Antilles Received 2 March 2004; received in revised form 5 May 2004; accepted 5 May 2004 Abstract Zoning schemes that are becoming an important management tool in large marine reserves, are difficult to implement in small reef areas. At the 3.4 km long reef of Eilat (Red Sea), a small (ca. 350 m of coastline) enclosure strategy has been enforced since 1992, while the remaining reef was left open to intense human activities. Here we have investigated for 2.5 y three populations of the branching coral Stylophora pistillata (3605 colonies) in a locality within the enclosed area (site NR) and in two areas open to the public, by tossing random quadrats at the shallow lagoonar zone (0.5–1.5 m depth). In the two open sites we found significantly higher levels of colony breakage (14–34% vs. 4–9% in the enclosed site), lower partial mortality levels of colonies (in the first 1.5 y; 7– 9% vs. 23–30% at NR), higher recruitment (up to 3.0 vs. up to 0.9 colonies/m 2), 50% reduction in coral life span (10 vs. 20 y) and an estimated extinction period of 9–10 y for new cohorts as compared to >20 y in the enclosed site. Average colony size and maximal colony size were about half in the open sites. Live coverage fluctuated widely in all sites but was 3 times higher in the enclosed area (1.0–3.0% vs. 0.3–1.1%). Log-transformed size frequency distributions revealed, at the open sites, a shift from small towards me- dium-size classes and at the enclosed site, a shift from larger to medium size classes. We conclude that the enclosure of a limited core zone, although improved some ecological parameters, was not sufficient to compensate for stress imposed by anthropogenic ac- tivities. It is suggested to employ active restoration approaches, such as the ‘‘gardening concept’’, as supplementary management tools. Ó 2004 Elsevier Ltd. All rights reserved. Keywords: Corals; Eilat; Gardening; Human impact; Marine protected areas; Restoration; Stylophora pistillata 1. Introduction The practice of proclaiming marine ecosystems as marine protected areas (MPAs) and marine reserves are fundamental legislative steps in the conservation of marine habitats (Kelleher and Kenchington, 1992; Gubbay, 1995; Kelleher, 1996; Barr and Thornton, 1998; Tuya et al., 2000).Many of the model MPAs consist of large ecosystems, encompassing a variety of coastal and oceanic habitats. Best known example is the Great Barrier Reef Marine Park in Australia (GBRMP). In the GBRMP, the world’s largest MPA, a zoning scheme has been successfully applied, with three major zones of management: conservation areas (core zones), permitted use areas (National Park zones), and general use zones. In other MPAs, highly sensitive grounds, e.g., nurseries and spawning sites, receive additional special protection measures such as the adaptation of no-use legislation (Christensen et al., 1996) or consideration of connectivity and larval capabilities to migrate geo- graphic distances far greater than the protected area size (Ogden, 1997; Roberts, 1997; Allison et al., 1998). In * Corresponding author. Tel.: +972-4-8565275/+972-4-8515202; fax: +972-4-8511911. E-mail address: buki@ocean.org.il (B. Rinkevich). 0006-3207/$ - see front matter Ó 2004 Elsevier Ltd. All rights reserved. doi:10.1016/j.biocon.2004.05.001 Biological Conservation 121 (2005) 243–255 www.elsevier.com/locate/biocon BIOLOGICAL CONSERVATION