Ecosystem Effects Of Fishing

Most of the major impacts of fishing on the ecosystems recorded around the world occur in the Mediterranean. This variety of interactions is due to four main interrelated factors: the wide range of fishing gear and practices; very intensive fishing; a high diversity of exploited habitats, ranging from shallow water to the deep-sea and oceanic domain; and high biological diversity.

Fluctuations and declines in marine fish populations have caused growing concern among marine scientists, fisheries managers, commercial and recreational fishers, and the public. Sustaining Marine Fisheries explores the nature of marine ecosystems and the complex interacting factors that shape their productivity. The book documents the condition of marine fisheries today, highlighting species and geographic areas that are under particular stress. Challenges to achieving sustainability are discussed, and shortcomings of existing fisheries management and regulation are examined. The volume calls for fisheries management to adopt a broader ecosystem perspective that encompasses all relevant environmental and human influences. Sustaining Marine Fisheries offers new approaches to building workable fisheries management institutions, improving scientific data, and developing management tools. The book recommends ways to change current practices that encourage overexploitation of fish resources. It will be of special interest to marine policymakers and ecologists, fisheries regulators and managers, fisheries scientists and marine ecologists, fishers, and concerned individuals.

Reef ecosystems extend throughout the tropics. Exploited by small-scale fishers, reefs supply food for millions of people, but, worldwide, there are growing worries about the productivity and current state of these ecosystems. Reef fish stocks display many features of fisheries elsewhere. However, habitat spatial complexity, biological diversity within and among species, ecosystem intricacy and variable means of exploitation make it hard to predict sustainable modes and levels of fishing.

Recent scientific literature has raised many concerns about whether fisheries have caused more extensive changes to marine populations and ecosystems than previously realized or predicted. In many cases, stocks have been exploited far beyond management targets, and new analyses indicate that fishing has harmed other species—including marine mammals, seabirds, sea turtles, and sea grasses—either directly through catch or habitat damage, or indirectly through changes in food-web interactions. At the request of the National Oceanic and Atmospheric Administration, the National Research Council conducted an independent study to weigh the collective evidence for fishery-induced changes to marine ecosystems and the implications of the findings for U.S. fisheries management. Dynamic Changes in Marine Ecosystems provides comprehensive information in regard to these findings.

"By examining a suite of over 90 indicators for nine major U.S. fishery ecosystem jurisdictions, Link and Marshak systematically track the progress the U.S. has made toward advancing ecosystem-based fisheries management (EBFM) and making it an operational reality. Covering a range of socioeconomic, governance, environmental forcing, major pressures, systems ecology, and fisheries criteria, they evaluate progress toward EBFM in the U.S., covering a wide range of longitude, latitude, and parts of major ocean basins, representing over 10% of the world’s ocean surface area. They view progress toward the implementation of EBFM as synonymous with improved management of living marine resources in general, and highlight lessons learned from a national perspective. Although US-centric, the lessons learned are applicable for all parts of the global ocean. Though much work remains, significant progress has been made to better address many of the challenges facing the sustainable management of our living marine resources"--Publisher's description.

Over-exploitation of the world's fish resources receives considerable attention and is a source of justifiable concern. However, fishing does much more than simply remove the species of interest. What are the other problems that fishing might cause? Are there knock-on effects caused by removal of the target species for other parts of the system? What incidental damage does fishing cause and how much do we really know and understand about the consequences of our actions? The Effects of Fishing on Marine Ecosystems and Communitites draws together, within one volume, an expert and comprehensive assessment of the problem.

Concerns over the potential ecological effects of fishing have increased with the expansion of fisheries throughout the marine waters of the United States. Effects of Trawling and Dredging on Seafloor Habitat describes how assessment of fishing impacts depends on gear type, number and location of bottom tows, and the physical and biological characteristics of seafloor habitats. Many experimental studies have documented acute, gear-specific effects of trawling and dredging on various types of habitat. These studies indicate that low mobility, long-lived species are more vulnerable to towed fishing gear than short-lived species in areas where the seabed is often disturbed by natural phenomena. Trawling and dredging may also change the composition and productivity of fish communities dependent on seafloor habitats for food and refuge. The scale of these impacts depends on the level of fishing effort. This volume presents color maps of fishing effort for all regions with significant bottom trawl or dredge fisheries-the first time that such data has been assembled and analyzed for the entire nation.