Cover Image


View/Hide Left Panel

the infancy of the emerging theoretical framework required to interpret the results (Knowlton, 1992; Scheffer et al., 2001; Hsieh et al., 2005).

Much new data and analyses have appeared in the last 5 years, sometimes with sharply conflicting interpretations, about the magnitude and rates of change in abundance of particular species. Regardless of these uncertainties, however, it is increasingly apparent that all of the different kinds of data and methods of analysis point in the same direction of drastic and increasingly rapid degradation of marine ecosystems. Here, I examine some of the most important of these new results since the publication of my previous synthesis (Jackson et al., 2001), with emphasis on coastal seas and estuaries, continental shelves, the open ocean pelagic realm, and coral reefs, about which I am most familiar. The biology and substantial threats to the ecology of the deep sea have been recently reviewed by Koslow (2007) and are not considered here. I then discuss what I believe will be the future of marine ecosystems if the drivers of change continue unabated, and address the kinds of changes in patterns of consumption and energy use that will be required to turn the situation around.


People have congregated along the coast from the beginnings of humanity, and the cumulative effects of exploitation, habitat destruction, and pollution are more severe in estuaries and coastal seas than anywhere else in the ocean except for coral reefs.

Bay of Fundy

New detailed studies of the Quoddy region of the Bay of Fundy (Lötze and Milewski, 2004) and the Wadden Sea (Lötze, 2005; Lötze et al., 2005) confirm and refine conclusions developed earlier based primarily on studies of Chesapeake Bay and Pamlico Sound (Jackson, 2001; Jackson et al., 2001). The Bay of Fundy is particularly interesting because ecological degradation is so great despite comparatively good water quality compared with most other estuaries (Lötze, 2005; Lötze et al., 2006). Exploitation began with whaling and hunting and fishing of other marine mammals, birds, and cod. The 16 original mammal species present before European contact were hunted to very low levels by 1900, with 3 extinct species including the sea mink Mustela macrodon, Atlantic walrus Odobenus rosmarus rosmarus, and possibly the coastal northwest Atlantic gray whale Eschrichtius robustus, as well as 7 more species that were severely reduced (Lötze and Milewski, 2004). Subsequent protection resulted in strong recovery of pinnepeds, but whales have not recovered, including the northern right whale, which has declined from an estimated popula-

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement