. "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.
The following HTML text is provided to enhance online
readability. Many aspects of typography translate only awkwardly to HTML.
Please use the page image
as the authoritative form to ensure accuracy.
In the Light of Evolution: Volume II—Biodiversity and Extinction
TABLE 1.3 Status and Trends of Major Ocean Ecosystems Defined by Principal Symptoms and Drivers of Degradation in the >99% of the Global Ocean That Is Unprotected from Exploitation
Coral reefs: Critically endangered
Symptoms: Live coral reduced 50–93%; fish populations reduced 90%; apex predators virtually absent; other megafauna reduced by 90–100%; population explosions of seaweeds; loss of complex habitat; mass mortality of corals from disease and coral bleaching
Drivers: Overfishing, warming and acidification due to increasing CO2, runoff of nutrients and toxins, invasive species
Estuaries and coastal seas: Critically endangered
Symptoms: Marshlands, mangroves, seagrasses, and oyster reefs reduced 67–91%; fish and other shellfish populations reduced 50–80%; eutrophication and hypoxia, sometimes of entire estuaries, with mass mortality of fishes and invertebrates; loss of native species; toxic algal blooms; outbreaks of disease; contamination and infection of fish and shellfish; human disease
Drivers: Overfishing; runoff of nutrients and toxins; warming due to rise of CO2; invasive species; coastal land use
Continental shelves: Endangered
Symptoms: Loss of complex benthic habitat; fishes and sharks reduced 50–99%; eutrophication and hypoxia in “dead zones” near river mouths; toxic algal blooms; contamination and infection of fish and shellfish; decreased upwelling of nutrients; changes in plankton communities
Drivers: Overfishing; trophic cascades; trawling; runoff of nutrients and toxins; warming and acidification due to rise of CO2; introduced species; escape of aquaculture species
Open ocean pelagic: Threatened
Symptoms: Targeted fishes reduced 50–90%; increase in nontargeted fish; increased stratification; changes in plankton communities
Drivers: Overfishing; trophic cascades; warming and acidification due to rise of CO2
Coastal ecosystems are endangered to critically endangered on a global scale. The lesser endangerment of pelagic ecosystems reflects their remoteness from all factors except fishing and climate change, although there are no real baselines for comparison to critically evaluate changes in plankton communities. This grim assessment begs the question, What are the projected long-term consequences for the ecological condition of the ocean if we continue with business as usual?
Predicting the future is, at best, a highly uncertain enterprise. Nevertheless, I believe we have a sufficient basic understanding of the ecological