Mother Jones has a section devoted to marine conservation that includes a number of excellent articles and FAQs on critical issues such as:

* Not Enough Fish in the Sea: The causes and consequences of overfishing
* How to Catch a Fish: Modern methods are more efficient than ever–and more destructive
* Catch as Catch Can: Millions of marine animals are killed “incidentally” every year
* Aquaculture: Fish farming offers a solution to overfishing; but is the environmental cost too high?
* Who’s In Charge Here? Government and the ocean
* Marine Pollution: How the ocean became a toxic waste dump
* Development: Are we loving our coasts to death?
* Coral Reefs: There’s still time to save some reefs, but just barely

For these articles and more see:
http://motherjones.com/special-reports/2006/03/last-days-ocean