Articles

• The Key to Molting: Soft-Shell Crabs
• 10 Questions on COSEE: CGOM
• Pace Joins MASGC Legal Program
• Goecker Hired as Habitat Restoration Specialist
• Scientists Study Populations of Submerged Seagrasses
• Featured Publication
• Guest Editorial

Sea Briefs is a report on the results of the Mississippi-Alabama Sea Grant Consortium.

Editor: Melissa Schneider

Masthead photo: Steven C. Zinski/bluecrab.info

This newsletter is available in PDF format from:
masgc.org/seabriefs

MASGC supports applied, interdisciplinary marine science research, education and outreach efforts to foster the sustainable development and management of the Mississippi and Alabama coasts and nearshore ecosystems of the Gulf of Mexico

Mississippi-Alabama
Sea Grant Consortium
703 East Beach Drive
Ocean Springs, MS 39564
Phone: 228-818-8838
E-mail: seabriefs@masgc.org
MASGP 09-011-03

Scientists study populations
of submerged seagrasses
Habitats have top economic values

A team of scientists is surveying bays and a bayou at the Grand Bay National Estuarine Research Reserve to determine what factors make seagrass beds appear, disappear and reappear.

“Seagrass beds are one of the most important essential fisheries habitats,” said Hyun Jung “J.” Cho, assistant professor in the biology department at Jackson State University. “They provide nursery and foraging grounds for crabs, shrimp, fish and waterfowl.”

Seagrasses have many other benefits. Their roots hold sediment, which helps reduce increasing turbidity and curb sediment re-suspension. Above the ground, seagrass shoots help protect shorelines from erosion by buffering wave energy. And, because they remove nutrients from the water, sea grasses help prevent harmful algal blooms, which cause fish kills.

Seagrass beds also top the charts when it comes to economic value per acre, Cho said, making them some of the most valuable habitat in the world.

Surveys in recent years show that only two seagrasses are present at the Grand Bay National Estuarine Research Reserve: wigeon grass (Ruppia maritima) and shoal grass (Halodule wrightii).

In additional research, Cho and Patrick Biber, an assistant professor at The University of Southern Mississippi Gulf Coast Research Laboratory (GCRL), are using funding from the Mississippi-Alabama Sea Grant Consortium to work to develop protocols for propagating wigeon and shoal grasses and planting them in bayous. By collecting seeds from grass beds instead of uprooting the grasses, scientists keep the natural habitat intact.

They germinate the seeds in a lab, grow them in an indoor tank and greenhouse and eventually plant them in bayous and estuaries. Scientists have tried transplanting wigeon grass using peat pots, peat pellets and biodegradable mats to help them take hold underwater.

Growing seedlings in peat pots and planting the entire pot in submerged sediment seems to be showing the most promise. But, seagrass restoration test plots in Bayou Cumbest and at GCRL are showing just how difficult it is to plant seagrasses and see them successfully take root.

“Only peat pots showed success, presumably because of the larger soil volume, allowing a more stable substrate for the plants to remain anchored after transplanting,” Biber said.

There are several factors that make seagrass restoration challenging. There is a lack of source material, and plants often need to be harvested from already declining meadows, Biber said.

High plant mortality can be attributed to inappropriate water quality or sediment disturbance. And, plants often are washed away or underwater sediment is fluidized after seagrasses are planted.“This makes the long-term success of seagrass transplanting particularly challenging in all but the most quiet and calm conditions, which are rare in the ocean,” Biber said.