سابقه زیست محیطی بهره برداری

In Puget Sound, WA (USA), rockfish (Sebastes spp.) have significantly declined in abundance, with multiple petitions to list individual species under the Endangered Species Act. In order to better understand the ecological legacy of rockfish fishing to the Puget Sound ecosystem, the local history of rockfish exploitation was reviewed, focusing on the socioeconomic forces and management decisions which influenced the trajectory of landings. Rockfish have always been harvested for human consumption in the region, but over time exploitation patterns have changed from an opportunistic subsistence activity by indigenous peoples, to a year-round target of commercial and recreational interests. Annual commercial and recreational harvests together peaked (almost 400 mt) in the early 1980s as anglers’ attitudes changed, gear technology improved, rockfish became more familiar to the market, human population increased, and agency programs promoted fisheries to sustain employment. Rockfishes were generally not managed intensely or with conservation goals in mind until the late 1980s, in part due to scientific shortcomings and a lack of resources. By the time management actions were deemed necessary, the greatest harvest had already occurred. However, the low intrinsic productivity of most rockfish species suggests that the legacy of fishing will remain for years to come. As managers strive to restore the integrity and resilience of Puget Sound, they must realize the significance of historical fishery removals to the ecosystem and use the proper social and economic incentives to drive individual behavior toward these ecosystem goals.

In recent years both fisheries scientists and marine conservation biologists have looked to the past to uncover how historical impacts shaped current ecosystems and to use historical conditions as reference points for the recovery of degraded ecosystems [1], [2], [3] and [4]. In the case of fisheries, there is clear recognition that the history of exploitation has influenced the structure and function of present-day marine ecosystems, and understanding the ecological legacy of fisheries can increase the effectiveness of management aimed at recovering degraded ecosystems. Importantly, historical perspectives on fisheries management may also highlight constraints to management efforts since the historical legacy of decades of fishing may limit policy and management options. Understanding the history of management is particularly important in long-lived, low-productivity species [5]. For such species, effects of humans may not be evident for many years, thus introducing a response lag from population impact to management need. For instance, the demise of juvenile and subadult sea turtles lost through harvest or bycatch may have remained unseen and unrealized because human monitoring focused on adult nesting females, who delay maturity for 10–60 years [6]. Similarly, the feedback lag between management action and population response may be protracted in long-lived fish populations with long generation times, delayed maturity, and sporadic recruitment. Rockfishes (Sebastes spp.) are a diverse group of marine fishes (about 102 species worldwide and at least 72 species in the northeastern Pacific) [7], and as a group, are among the most common groups of bottom and mid-water dwelling fish on the Pacific coast of North America [8]. Adult rockfish can be the most abundant fish in various coastal benthic habitats, from shallow coastal habitats, such as kelp forests, to deep submarine canyons. Despite their ubiquity, rockfishes tend to have a number of life history traits that make them susceptible to fishing or other anthropogenic perturbations. In general, rockfish have long life spans, often exceeding 50 years, are slow to mature, and have very low first-year survival, resulting in long generation times [8]. Successful recruitment from a pelagic larval to juvenile stage is highly variable [9], [10] and [11], thus making recovery of depleted rockfish populations slower than might be expected given their high fecundity. Moreover, adults typically show limited movement [12], and thus rockfish often exist as metapopulations with local subpopulations connected by the dispersal of pelagic juveniles [13]. Along the west coast of the US, a number of rockfishes have undergone substantial declines over the last three decades [14], [15], [16] and [17], with several species now considered overfished [18]. Likewise, a number of rockfishes have showed significant reductions in abundance over the last 30 years in Puget Sound, which has a unique but considerably less diverse rockfish assemblage (28 spp) than the outer coast (40 spp) [8] and [19]. These declines led to petitions to list 14 Puget Sound rockfish species under the US Endangered Species Act (ESA) in 1999. The National Marine Fisheries Service (NMFS) declined to review 11 of the 14 species citing a lack of information necessary to conduct a formal status review [20], and after conducting a status review of the remaining three species (copper rockfish Sebastes caurinus, quillback rockfish S. maliger, and brown rockfish S. auriculatus), NMFS concluded that ESA listing was not warranted [21]. However, in 2007 NMFS received another petition to list five of the 11 rockfishes that were previously denied. These were bocaccio S. paucispinis, canary rockfish S. pinniger, yelloweye rockfish S. ruberrimus, greenstriped rockfish S.elongatus and redstripe rockfish S. proriger. After conducting a status review in 2009 [22], canary rockfish and yelloweye rockfish were proposed to be listed as threatened and bocaccio as endangered [23]. The history of fisheries exploitation of rockfish in Puget Sound is reviewed in this paper, with a focus on those species recently considered by NMFS for ESA listing. The review spans fisheries from pre-Euroamerican colonization to the present and details the timeline of exploitation. It also examines how socioeconomic forces and management decisions, coupled with scientific shortcomings of the time and the inherent ecology of rockfishes, paralleled the trajectory of landings in Puget Sound.

The abundance of Puget Sound rockfishes as a group have declined about 70% over the last 40 years, with some larger species, such as bocaccio, canary rockfish, and yelloweye rockfish showing even greater declines [22]. Although a variety of factors (e.g., harvest, pollution, habitat alteration) share some blame for these declines, it is generally agreed that overfishing played a leading role, considering both the historical magnitude of the fishery removals and more recent comparisons of rockfish density and size in no-take marine protected areas to fished areas [19] and [22]. Indeed, such trends in Puget Sound are a microcosm of the global challenge facing stocks of fish arising from innovative and potent technology, mounting market demand, restoration of indigenous people's rights, societal need for jobs, recreation, and allocation equity [65]. Understanding and heeding the institutional, social, and economic forces that shape the use of fish populations is therefore essential as we learn to better manage marine ecosystems and the fisheries that depend on them [66]. Exploitation patterns of rockfish in Puget Sound have changed substantially over time, evolving from an opportunistic subsistence activity to a year-round focus of commercial and recreational harvest. An array of socioeconomic forces has driven these exploitation patterns, assisted by federal and state institutions that actively promoted rockfish harvests under a regulatory framework that was often slow to respond to species’ declines. The demise of Puget Sound rockfish stocks may be conveniently attributed to mismanagement and lack of scientific resources. However, sustainable management has been similarly elusive in other regions [67], including the California Current where rockfish are important fishery targets and have been regulated based on a preponderance of scientific research [17] and [68]. Emerging examples from elsewhere reinforce the view that fisheries and ecosystem management systems succeed most often when they use the proper social and economic incentives to drive individual behavior in a way that is also considered optimal for society [67] and [69]. Puget Sound may also represent a model for examining the ecosystem effects of overexploiting vulnerable species, and more importantly, understanding how the ecological legacy of exploitation may constrain ecosystem recovery efforts [2]. Rockfish catch, exploitation, and regulatory policies in Puget Sound have generally presaged US Pacific Coast trends [17]; for example, bottom trawling has been banned in southern Puget Sound for the last 20 years. Fishing has been shown to disproportionately affect rockfish and other large, slower growing species with late maturation and sporadic recruitment [15] and [70]. Therefore, historical analysis of structural changes and trends in the rest of the Puget Sound groundfish assemblage could offer some insight into the temporal scale of ecosystem recovery after the cessation of fishing, or even reveal community phase shifts which affect recovery [71]. Undoubtedly, policy actions (and inactions) that inadvertently cause more vulnerable species to be harvested can have ultimate, but unintentional, consequences not only for those species, but also entire ecosystems [69] and [72]. The most intensive exploitation of reef-associated rockfish in Puget Sound was fairly short-lived (approximately 20 years, 1970–1990), yet the low intrinsic productivity of most species means that the legacy of fishing will remain for years to come. Institutions charged with restoring Puget Sound ecosystem must begin the difficult process of balancing imperfect knowledge with the need to make resource allocation decisions within a constantly changing socioeconomic environment [66]. Furthermore, they must steadily work to resolve scientific shortcomings of the past. Whether or not the scientific and management community of Puget Sound can rise to the challenge remains to be seen. To paraphrase Norman Cousins, the history of rockfish exploitation in Puget Sound serves as a “vast early warning system”, and it is clear we would do well to heed the lessons of the past. Acknowledgments Thanks to Aaron Dufault, who ably assisted in many aspects of literature review, acquisition, and data entry. We are grateful to WDFW biologists Ray Buckley, Greg Bargmann, Debbra Bacon, and Greg Lippert for sharing literature, photographs, and insight into historic fisheries. Robert Kopperl of Northwest Archaeological Associates, Inc. and Laura Phillips from the University of Washington's Burke Museum greatly improved our understanding of the zooarchaeological literature and the study of fish bones. Thanks to Carolyn Marr and the Seattle Museum of History and Industry for access to photography archives, and specifically, Karl House of the Puget Sound Maritime Historical Society who sorted through photographs and provided his time and guidance. Craig Wilson, NWFSC librarian, somehow always produced obscure documents that we thought to be unobtainable. Discussions with and reviews by Anne Beaudreau, Chris Harvey, and Ray Buckley greatly improved the manuscript. This manuscript emerged as an outgrowth of the biological review team's (BRT) 2009 examination of historical catch data for rockfish proposed for ESA listing in Puget Sound.