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Marylanders Grow Oysters

Growing oysters gives citizen volunteers an opportunity to learn about our river and to be a part of the effort to restore it.

photos by Tyler Campbell

The Chester River Association leads the Marylanders Grow Oysters (MGO) program on the Chester River. Hosting oyster cages gives people an opportunity to clean up their local waters; provides an educational opportunity for people to learn about oysters and our river ecosystem; and increases the number of oysters we plant in the Chester.
If you are interested in joining the MGO program on the Chester River, please contact Isabel Hardesty.

2014-2015: 50 docks hosted 236 oyster cages; about 47,200 oysters.
2013-2014: 55 docks hosted 291 oyster cages; about 43,650 oysters.
2012-2013: 30 docks hosted 250 oyster cages; about 50,000 oysters.

View photos on Facebook .
Read about the Marylanders Grow Oysters state program here.
Discover the types of critters you might find among your oysters here.
Download information on the MGO program on the Chester here.

The state-wide Marylanders Grow Oysters program is designed to foster stewardship and re-establish local oyster populations in state-designated sanctuaries. Citizen volunteers with waterfront access are given mailbox-sized cages filled with spat to be hung on their piers so the oysters can grow without the threat of predation and siltation. With careful maintenance and periodic dunking of the cages to prevent siltation, the oysters will be ready to transplant to a local oyster sanctuary in about 9 months. This community based natural resource management program allows members of the Chester River watershed to take action in cleaning up their local waters. In the Chesapeake Bay, the Marylanders Grow Oysters program boasts almost 30 programs in creeks and river, caring for over 8,000 cages of spat-on-shell. With about 300 oysters per cage, that's over 2 million oysters planted in the Bay every year!

 Checking out the oysters - by Mike Hardesty

Oyster Care

Oysters need a certain level of salinity in order to grow - in the Chester, that means oysters can reliably grow down-river of Southeast Creek. Chester River water up-river of Southeast Creek tends to be too fresh for oysters to thrive.

Water Depth: Cages need to be suspended in the water column - off of the muddy bottom so the oysters don't suffocate and under water at low tide during the winter so they are not exposed to freezing air or trapped in ice. (Oysters can be exposed to warm air for a number of hours and survive, but even short periods of exposure to freezing air can kill them.) A good rule of thumb is to have two feet of water at your lowest tide, minimum.

Securing Cages: Cages need to be secure and easily retrievable. Underneath a dock is a great place - the pilings allow for easy tie-off and the cages and lines will not become a navigation issue. You must be able to routinely access the cages for maintenance in all seasons.

Maintenance & Monitoring: Dunking the cages once or twice a week will help keep silt and sediment off the oysters. Sediments can suffocate the vulnerable spat. Once the water warms, the cages will begin to foul with algae growth. Taking the cages out of the water and allowing them to dry for 2 hours will help limit fouling. If fouling becomes heavy, scrubs the cages with a wire brush.

Program Timeline

September: Oyster Recovery Partnership delivers cages and bags with spat-on-shell. First-year growers come and collect cages and spat; current members collect spat.

October-February: Dormant period due to falling water temperatures. Be mindful of low tides and ice on lines. Periodic dunking prevents siltation.

March: Oysters are feeding more; make sure cages and oysters are free of mud to allow water to flow freely.

April: Oysters are actively feeding and may reach dime size. Maintain cages to prevent fouling.

Filling cages with spat-on-shell - by Mike Hardesty

: Oysters are collected and planted on an oyster sanctuary in Langford Bay. Store cages out of the water in a dry place for the summer; this rids them of algae and mud.

June-August: Watch your email for notices of fun, oyster-related events for MGO volunteers. Events could include a trip to Horn Point Laboratories to see where spat are grown, a movie night to watch an oyster documentary, or a picnic to thank our MGO volunteers.


Oyster stewardship efforts on the Chester first began with The Center for Environment & Society at Washington College in 2008 with volunteers and 25 floats at Eastern Neck National Wildlife Refuge. Funded by a grant from the Friends of Eastern Neck, these projects culminated in the planting of 20 bushels of oysters on a new oyster bar at Hail Cove in September, 2009.

In 2010, the College partnered with the Marylanders Grow Oyster program to continue restoration projects along the Chester River. In the spring of 2013, the Chester River Association took over management of the program in an effort to increase outreach and education within the community and to increase the numbers of oysters being grown by citizen volunteers and planted in the river.

                                                                                Oysters in cages - by Mike Hardesty