Eelgrass provides a refuge from predators for some fish species

The meadows of eelgrass found in lagoons along the Atlantic seacoast have a long history of providing a habitat for fish and invertebrates of many species. Despite this long history, it has proven difficult to document and quantify the relationships between eelgrass cover and the abundance of fish and crabs on a larger scale.

An article in the current issue of the journal Marine Ecology Progress Series describes experiments by URI Graduate School of Oceanography (GSO) biological oceanographers Lora Harris, Betty Buckley, Scott Nixon, and Ben Allen to investigate how different habitats affect predator-prey relationships. The three habitats in the study included eelgrass Zostera marina, macroalgae, and bare sediment.

The study was supported by Rhode Island Sea Grant and carried out in the Lagoon Mesocosm Facility, located at the GSO’s Narragansett Bay Campus.

Mesocosms containing marine sediments, coastal water, and varying densities of eelgrass or macroalgae were used to simulate conditions found in shallow coastal lagoons of Rhode Island. Bluefish, commonly found in Narragansett Bay and Rhode Island salt ponds, were used as predators in each experiment after appropriate acclimation in each habitat type. Prey fish were provided in equally weighted rations and included silversides, tautog, cunner, and menhaden, all species found in local eelgrass meadows and all part of the bluefish diet.

The scientists found that the presence of eelgrass significantly increased survival of silversides, tautog, and cunner even at very low shoot densities. Experiments using macroalgae did not result in significantly different survival rates between bare sand and macroalgae habitat for silversides or cunner, the two species tested for this vegetation type.

“These findings confirm the hypothesis that eelgrass habitats serve a functional role as refuges from predation for some prey fish,” said Harris. “Studies have shown that the more structurally complex a habitat is, the more significant the decline in predation.

“Our results provide better insight into the different habitat value of eelgrass meadows. The findings support a continuation of efforts to protect and manage eelgrass meadows effectively.”

Media Contact

Lisa Cugini EurekAlert!

More Information:

http://www.uri.edu

All latest news from the category: Ecology, The Environment and Conservation

This complex theme deals primarily with interactions between organisms and the environmental factors that impact them, but to a greater extent between individual inanimate environmental factors.

innovations-report offers informative reports and articles on topics such as climate protection, landscape conservation, ecological systems, wildlife and nature parks and ecosystem efficiency and balance.

Back to home

Comments (0)

Write a comment

Newest articles

Lighting up the future

New multidisciplinary research from the University of St Andrews could lead to more efficient televisions, computer screens and lighting. Researchers at the Organic Semiconductor Centre in the School of Physics and…

Researchers crack sugarcane’s complex genetic code

Sweet success: Scientists created a highly accurate reference genome for one of the most important modern crops and found a rare example of how genes confer disease resistance in plants….

Evolution of the most powerful ocean current on Earth

The Antarctic Circumpolar Current plays an important part in global overturning circulation, the exchange of heat and CO2 between the ocean and atmosphere, and the stability of Antarctica’s ice sheets….

Partners & Sponsors