%0 Journal Article %T Tempering Expectations of Recovery for Previously Exploited Populations in a Fully Protected Marine Reserve %A Jennifer K. Schultz %A Joseph M. O'Malley %A Elizabeth E. Kehn %A Jeffrey J. Polovina %A Frank A. Parrish %A Randall K. Kosaki %J Journal of Marine Biology %D 2011 %I Hindawi Publishing Corporation %R 10.1155/2011/749131 %X Centuries of resource extraction have impacted coral reef ecosystems worldwide. In response, area and fishery closures are often enacted to restore previously exploited populations and reestablish diminished ecosystem function. During the 19th and 20th centuries, monk seals, pearl oysters, and two lobster species were overharvested in the Northwestern Hawaiian Islands, now managed as the Papah¨¡naumoku¨¡kea Marine National Monument, one of the largest conservation areas in the world. Despite years of protection, these taxa have failed to recover. Here, we review each case, discussing possible factors that limit population growth, including: Allee effects, interspecific interactions, and time lags. Additionally, large-scale climate changes may have altered the overall productivity of the system. We conclude that overfishing of coral reef fauna may have broad and lasting results; once lost, valuable resources and services do not quickly rebound to pre-exploitation levels. In such instances, management options may be limited to difficult choices: waiting hundreds of years for recovery, actively restoring populations, or accepting the new, often less desirable, alternate state. 1. Introduction For centuries, coral reef ecosystems have been viewed as renewable resources, from which countless organisms have been harvested to serve dependent human communities [1, 2]. There is an underlying assumption that marine species are highly resilient to large population reductions and that abundance may be quickly restored by area or fishery closures [3¨C5]. The capacity for self-repair, however, is dependent upon the extent of human impact and system resilience [6, 7]. Excessive and prolonged anthropogenic exploitation may reduce resilience, that is, the capacity of a system to persist while maintaining key relationships and absorbing disturbances [8]. For example, 15 years after fishery closures, there has been little recovery of several marine fish stocks that were previously reduced 45%¨C99% [9, 10]. Thrush and Dayton [11] review several examples of marine ecosystem ratchets, in which recovery to pre-exploitation levels is no longer possible [12]. In such instances, managers are forced to accept the new, often less desirable, alternate ecosystem state. The Northwestern Hawaiian Islands (NWHI) span the center of the Hawaiian-Emperor seamount chain, the world¡¯s most geographically isolated archipelago (Figure 1) [13]. As of 2006, these small islands, atolls, reefs, and surrounding areas comprise the Papah¨¡naumoku¨¡kea Marine National Monument, one of the largest marine %U http://www.hindawi.com/journals/jmb/2011/749131/