. "1 Ecological Extinction and Evolution in the Brave New Ocean--JEREMY B. C. JACKSON." In the Light of Evolution, Volume II: Biodiversity and Extinction. Washington, DC: The National Academies Press, 2008.
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In the Light of Evolution: Volume II—Biodiversity and Extinction
tion of 10,000–15,000 in the northwest Atlantic to a mere 300 individuals. Among the 83 species of birds from the region, 40% have declined severely, including 3 species that were locally extirpated and another 3 hunted to extinction. Salmon were heavily exploited before records began, but even the stocks remaining in 1890–1900 were reduced by a further 99.5% by the end of the 20th century. The big three marine groundfish—cod, pollock, and haddock—were severely reduced before 1900, as elsewhere (Lötze and Milewski, 2004; Rosenberg et al., 2005), and catches were further reduced to just 3–37% of 1900 values by 2000. At the same time, several noncommercial species increased greatly in abundance. By the time scientific surveys began in 1970, groundfish were being rapidly replaced by shellfish and seaweeds as the major fisheries that are now also in decline (Lötze and Milewski, 2004).
Global Patterns of Exploitation
Suggestions that we had somehow focused on only the worst-case scenarios in our article on overfishing (Jackson et al., 2001) were addressed by an exhaustive review of 12 coastal seas and estuaries worldwide for which extensive archeological, historical, and early scientific data were available (Lötze et al., 2006). We examined ≈80 species or species groups that were assigned to six major taxonomic groups and seven ecological guilds. Average global degradation ranged from a low of 39% for crustaceans to 91% for oysters (Table 1.1). Levels of overall degradation for all major taxo-
TABLE 1.1 Percent Decline (Biomass, Catch, Percent Cover) for Fauna and Flora from Various Marine Environments