The Science

Marine Protected Areas

Marine protected areas (MPAs) are protected spaces set aside in the ocean, or "underwater parks," similar to parks on land. MPAs come in all shapes and sizes, but are most effective when protecting areas rich in habitat. 

Why marine protected areas are needed

Real problems lurk below the ocean's sparkling surface along California's coast. For example:

• White abalone are on the verge of extinction
• Federal regulators issued emergency Rockfish closures in 2002
• Fish size declined 45% along the West Coast in the last 21 years
• 75% of California?s kelp forests have disappeared since the 1960s
• 90% of the big fish that existed in the 1950s are gone

California's ocean is in trouble - and MPAs can help solve current problems; and safeguard against future problems like global warming and ocean acidification.

The science is clear: marine protected areas work! 

MPAs protect entire ecosystems. From sharks to seastars, every creature living in that space is protected. 

Extensive scientific research demonstrates that MPAs, and especially fully-protected marine reserves, can help bring back big fish and restore habitats. 

In PISCO's scientific survey of more than 100 reserves worldwide, scientists found:

• A 446% average increase in biomass of animals and plants
• A 166% average increase in number of plants or animals
• A 28% average increase in body size of animals
• A 21% average increase in animal and plant diversity
• A 1000% increase in of biomass and density of heavily fished species

Marine reserves allow fish, mammals, and other marine life to breed, feed, and succeed without human interference. Animals living inside marine reserves also help replenish fish populations outside their borders because the babies disperse in ocean currents, spilling over into unprotected areas. It's no coincidence that the majority of record-breaking game fish in Florida are caught just outside the marine reserve at Merritt Island.

The PISCO survey also looked to see how specific animals were doing in marine reserves and found:
• A 120% increase in the number of black grouper
• A 38% increase in the number of red grouper
• A 303% increase in the number of mutton snapper
• 6 times more lobster inside marine reserves than outside

Marine Reserves not only harbor more fish - they harbor bigger fish.  These bigger fish are important because they produce substantially more young.

Take for example the vermillion rockfish (pictured right). A vermillion rockfish that weighs close to two pounds produces about 150,000 baby fishes while a vermillion rockfish weighing 7.5 pounds produces 1.7 MILLION baby fishes. That?s a huge difference!

Big fish are key to making sure marine life populations remain healthy and stable and marine reserves are key to making sure enough bigger fish live long enough to repopulate the species.