In an article published in the May 26 issue of Science, scientists describe the first study to compare the top-down versus bottom-up human influences on the food chain of the kelp forest ecosystems.
The study was conducted by scientists at UCSB's National Center for Ecological Analysis and Synthesis, known as NCEAS, which is funded by the National Science Foundation.
"This study shows that California is on the right track by limiting fishing in certain areas in an effort to comply with the Marine Life Protection Act," said first author Ben Halpern, project director at NCEAS.
Kelp are giant algae that reach up to 120 feet in height and support diverse ecosytems. They provide beautiful settings for scuba diving and are rich areas for commercial and recreational fishing.
The research team took data from four years of marine life surveys by the National Park Service. The park service regularly checks 16 different kelp forest sites around the Channel Islands off the coast of Central California. They maintain data on 46 different species.
Next, the scientists matched the park service data to data provided by SeaWiFs, a satellite monitoring project that photographs and analyzes ocean color for information about ocean life. This information can then be used to estimate nutrient levels in the ocean.
Organic coastal run-off from fertilizers and sewage overflow increases the amount of organic material in the near shore ocean. According to the study, differences in the amount of organic material do not have much effect on the delicate foo
Contact: Gail Gallessich
University of California - Santa Barbara