Conclusions from a five-year study by scientists show that Marine Protected Areas (MPAs) in the Channel Islands National Park and Channel Islands National Marine Sanctuary to be effective in helping marine habitats to recover from overfishing.
“The findings of these first five years of monitoring shows consistent differences in abundance and size of species found within the MPAs versus the surrounding waters,” said John Ugoretz, manager of the Marine Habitat Conservation Program for the California Department of Fish and Game (DFG). “These data will help to inform future management of the region, aid in the implementation of the California Marine Life Protection Act in southern California, and contribute to our understanding of MPAs worldwide.”
“The Channel Islands reserves were designed to protect key ocean habitats, like kelp forests,” said Steve Gaines, director of the Marine Science Institute at the University of California, Santa Barbara. “Although we do not expect dramatic changes this quickly, some parts of the ecosystem have already benefited from protection.”
In 2002, the California Fish and Game Commission adopted a network of 10 marine reserves and two conservation areas within state waters that surround Channel Islands National Park and Channel Islands National Marine Sanctuary. After the MPA network went into effect in April of 2003, DFG assembled a cadre of marine experts to develop monitoring objectives for the MPAs.
During the past five years, scientists have monitored changes in marine animals and habitats as well as human activities in and around the MPAs. “We observed higher densities and bigger fish in marine reserves than in surrounding waters, including species that are targeted by fishing, such as kelp bass and California sheephead,” Jenn Caselle, research scientist with UC Santa Barbara, said regarding the scuba survey work conducted by the Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO) and the Channel Islands National Park. “This increase in the average size can have important ecological effects because larger fish produce exponentially more young than smaller fish.”
Preliminary research also indicates that the California spiny lobsters found within the MPAs are larger in size and in greater abundance than outside these protected areas. Mature large sized lobsters are essential to successful reproduction of this valuable fishery.
Scientists point out that the increase in California spiny lobster inhabiting the network is an indicator that MPAs can be an effective tool in ecosystem health. “All these MPA monitoring studies advance a broad understanding of how coastal ocean ecosystems respond to changes in management,” said Ugoretz.
Other species found off the California coast are expected to take longer to show change such as slow-growing rockfishes, which researchers say will need another 10 to 15 years to see major change. Research using a remotely operated vehicle found 8 to 12 of the finfish species monitored had greater densities within the MPAs than those outside.
One research project showed that nearly 96 percent of the vessels contacted by enforcement officers are in compliance with the state’s MPA rules and regulations. This is a positive sign that the MPAs are, for the most part, being respected.