Marine Protected Areas (MPAs) help conserve marine natural and cultural resources. They also facilitate recovery of diminished animal populations by protecting reproductive adults. A recent study published in Royal Society Open Science shows that the protection of a commonly eaten rockfish species in MPAs off the coast of Southern California may be helping the population outside of the protected area as well.
West Coast rockfish species were in deep collapse during the 1990s due to excessive fishing. There are at least 68 species of rockfish along the West Coast of the U.S., most of which are commonly eaten. They are a long-lived species, with some living until they are 50 years old and others over 100 years. Because they grow very slowly and are late to reproduce, Rockfish Conservation Areas (RCAs) along the entire length of the U.S. West Coast were established. Until now we did not know how these large-scale areas were not only protecting rockfish but also how they produce high abundances of fish larvae that can seed surrounding areas. This is good news for fisheries because it can build populations beyond the protected areas.
This study was done by the partnership of NOAA Fisheries’ Southwest Fisheries Science Center (SWFSC), University of San Diego and the University of Massachusetts Amherst. The researchers examined trends and data of rockfish larval numbers from 1998 to 2013 and found that larvae of most rockfish species increased throughout Southern California waters but especially within the protected conservation areas. During this time there were also largely cool ocean conditions which support rockfish reproduction. This is great news for the restoration of rockfish populations, as the data supports that conservation and management actions contribute to rockfish spawning success and the recovery of the fishery.
Journal reference:
Thompson, A.R., D.C. Chen, L.W. Guo, J.R. Hyde, and W. Watson. 2017. Larval abundances of rockfishes that were historically targeted by fishing increased over 16 years in association with a large marine protected area. Royal Society Open Science, 4(9):170639. DOI: 10.1098/rsos.170639.
