B. S. Halpern, S. Walbridge, K. A. Selkoe, C. V. Kappel, F. Micheli, C. D’Agrosa, J. Bruno, K. Casey, C. Ebert, H. Fox, Fujita.R., D. Heinemann, H. S. Lenihan, E. M. P. Madin, M. Perry, E. Selig, M. Spalding, R. Steneck, R. Watson, (2008). Science 319, 948-952.
Conservation prioritization and management of the oceans require spatially explicit information on how all types of human activities impact marine ecosystems, but methods for globally assessing such impacts and mapping their distribution have not previously existed. Using a novel ecosystem-specific and scale-independent model, we synthesized 17 global datasets on anthropogenic threats to 20 marine ecosystems. Results show that every part of the oceans is affected by humans and that a large fraction (34%) is heavily impacted, including both nearshore and offshore ecosystems in nearly every corner of the world. Although human impact on marine ecosystems is pervasive, areas of little impact remain, particularly near the poles. Our quantitative approach provides important guidelines for where conservation action and threat mitigation are most needed for achieving global management and conservation goals.