Oyster Upwellers

Gloucester pier.

Gloucester pier.

Over the course of 2017, we partnered with Maritime Gloucester to pursue a pilot project. We built and maintained an an upweller on Maritime Gloucester’s newly renovated main pier in downtown Gloucester. This exciting educational program to collect water quality data from water entering and exiting the upweller will measure the oysters’ impact on local water pollution.

Since 2017, we’ve started two additional upweller projects in a similar vein as our first upweller in Gloucester. 2019 will be our third year in Gloucester, and our second year at our two other locations: Marblehead and Hyannis.

At each site, we work with local partner.

  1. In Gloucester we work with Maritime Gloucester to develop educational curriculum and material for visitors and student groups.

  2. In Marblehead, we work with the Marblehead Charter School's Shark Club, a group of students interested in marine science. The students help with the maintenance and operation of the upweller.

  3. In Hyannis, we're working with the Barnstable Clean Water Coalition, a group whose focus is to improve Barnstable's water quality.

  In the beginning of the summer, each upweller gets approximately 60,000 baby oysters, called spat. They begin as the size of red pepper flakes, and will grow to about an inch by fall. At that point, the oysters will be released. 

  In the past two years, we’ve released over 200,000 native oysters. In 2019, we will release another 200,000.

 Current state regulations prohibit the release of oysters in restricted waters. Prior to release, we work with the Division of Marine Fisheries and the town's shellfish warden or constable to select appropriate release sites.


  In the summer of 2018, we conducted a habitat suitability study on the North Shore, and we identified locations well suited for oyster propagation. Oysters do best on hard substrates, such as rocks or pebbles, as opposed to sandy or muddy habitats. For this reason, oysters don't compete with clams for habitat. This is important on the North Shore, where the clam harvest is an important industry.