Featured Research

from universities, journals, and other organizations

Overfishing Puts Southern California Kelp Forest Ecosystems At Risk, Report Scientists

Date:
May 26, 2006
Source:
University of California - Santa Barbara
Summary:
Kelp forest ecosystems that span the West Coast -- from Alaska to Mexico's Baja Peninsula -- are at greater risk from overfishing than from the effects of run-off from fertilizers or sewage on the shore, say scientists at the University of California, Santa Barbara. The findings have important implications for the design of California's Marine Protected Areas. In an article published in Science, scientists describe the first study to compare the top-down versus bottom-up human influences on kelp forest ecosystems.

A California kelp forest creates a cathedral effect as the sun shines through the blades of the kelp.
Credit: NOAA

Kelp forest ecosystems that span the West Coast -- from Alaska to Mexico's Baja Peninsula -- are at greater risk from overfishing than from the effects of run-off from fertilizers or sewage on the shore, say scientists at the University of California, Santa Barbara. The findings have important implications for the design of California's Marine Protected Areas.

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 food chain of the kelp forest ecosystem. However removal of the fish at the top of the food chain has a profound effect.

When the predator species, such as rockfish, at the top of the food chain are removed, then the species that they normally eat, such as snails and barnacles, begin to increase in number. Many of these are herbivores that eat kelp. When their numbers increase, they decrease the amount of kelp, in turn changing how kelp forests look and the type of species that are associated with the kelp forest.

"Kelp forests are so sensitive," said Halpern. "If you remove some of the predators, then you can have an effect on the entire kelp forest ecosystem."

He explained that until now studies of kelp forests looked at either overfishing or increased nutrients. This is the first study to put both variables together to see which is more important.


Story Source:

The above story is based on materials provided by University of California - Santa Barbara. Note: Materials may be edited for content and length.


Cite This Page:

University of California - Santa Barbara. "Overfishing Puts Southern California Kelp Forest Ecosystems At Risk, Report Scientists." ScienceDaily. ScienceDaily, 26 May 2006. <www.sciencedaily.com/releases/2006/05/060525193843.htm>.
University of California - Santa Barbara. (2006, May 26). Overfishing Puts Southern California Kelp Forest Ecosystems At Risk, Report Scientists. ScienceDaily. Retrieved August 28, 2014 from www.sciencedaily.com/releases/2006/05/060525193843.htm
University of California - Santa Barbara. "Overfishing Puts Southern California Kelp Forest Ecosystems At Risk, Report Scientists." ScienceDaily. www.sciencedaily.com/releases/2006/05/060525193843.htm (accessed August 28, 2014).

Share This




More Earth & Climate News

Thursday, August 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Big Waves, Minor Flooding from Hurricane

Big Waves, Minor Flooding from Hurricane

AP (Aug. 27, 2014) Thundering surf spawned by Hurricane Marie pounded the Southern California coast Wednesday, causing minor flooding in a low-lying beach town. High surf warnings were posted for Los Angeles County south through Orange County. (Aug. 27) Video provided by AP
Powered by NewsLook.com
Calif. Quake Underscores Need for Early Warning

Calif. Quake Underscores Need for Early Warning

AP (Aug. 26, 2014) Researchers at UC Berkeley are testing a prototype of an earthquake early warning system that California is pursuing years after places like Mexico and Japan already have them up and running. (August 26) Video provided by AP
Powered by NewsLook.com
Hurricane Marie Brings Big Waves to California Coast

Hurricane Marie Brings Big Waves to California Coast

Reuters - US Online Video (Aug. 26, 2014) Huge waves generated by Hurricane Marie hit the Southern California coast. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Brazil Tries Genetically Modified Mosquitoes to Fight Dengue

Brazil Tries Genetically Modified Mosquitoes to Fight Dengue

AFP (Aug. 25, 2014) A factory in the industrial state of Sao Paulo produces genetically modified mosquitoes to fight dengue, a deadly tropical disease more prevalent in Brazil than anywhere else in the world. Duration: 00:57 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins