Bay Scallops in Tampa Bay — Tampa, Florida

Slowly, and not every year. The bay scallop once lived throughout the seagrass of Tampa Bay, but according to Tampa Bay Watch, in the early 1960s bay scallops vanished from Tampa Bay due to severe pollution from dredging and industrial waste. Restore America's Estuaries describes the same collapse, naming dredging operations and municipal waste as the cause, and reports that restoration work by Tampa Bay Watch and its partners has scallops slowly making a comeback.

The habitat has recovered faster than the scallops. Restore America's Estuaries cites Southwest Florida Water Management District mapping showing that Tampa Bay now supports 40,652 acres of seagrass, the largest amount measured since the 1950s. The Tampa Bay Estuary Program lists achieving a sustainable scallop population in Tampa Bay as a priority action in its Comprehensive Conservation and Management Plan, and notes that the first step is assessing the status and trends of the current population, which is where volunteer counts come in.

Since 1993, Tampa Bay Watch has organized an annual snorkel survey of the lower bay. On the day of the search, snorkelers working from boats and kayaks spread out over seagrass beds and count every scallop they find. Tampa Bay Watch lists the search areas as Middle and Lower Tampa Bay, Boca Ciega Bay, Emerson Point Preserve and the Dunedin Causeway, with launches from the Fort De Soto Park boat ramp, the Grandview Park boat ramp in St. Petersburg, Emerson Point Preserve in Palmetto and the Dunedin Causeway.

The event is large for a citizen science project. Restore America's Estuaries reported about 40 boats and 200 volunteers taking part each year, with support from the SeaWorld and Busch Gardens Conservation Fund and the Tampa Bay Estuary Program. In 2022 the Tampa Bay Water Atlas noted that snorkelers would search selected sites within Boca Ciega and Lower Tampa Bay on August 20, with shallow draft boats given priority. Bay News 9 reported that over 30 boats and 70 kayaks were spread out across Tampa Bay for the 30th search on August 2, 2025.

The 31st Annual Great Bay Scallop Search took place on Aug. 1, 2026, run by Tampa Bay Watch in partnership with the Tampa Bay Estuary Program and Pinellas County Environmental Management, with volunteers monitoring the population at three major locations. The 2026 search ran from 9 a.m. to 1 p.m., opening with a captain's meeting at 9 a.m. where boaters received instructions before heading out. Seagrass is the focus because, as the Tampa Bay Watch founder told Bay News 9 in 2025, it is the primary habitat where Tampa Bay scallops live, and the nonprofit says the count rises and falls with water quality, red tide and storms.

The totals swing widely. Tampa Bay Watch reports that the record high was set in 2009 with 674 scallops found, and that results vary annually with water quality, red tide, rainfall and storms. Restore America's Estuaries reported that in 2019, 51 scallops were found within the search perimeters, which it read as a sign that water quality was recovering after the 2018 red tide in the Tampa Bay region.

More recent years show the same volatility. Bay News 9 reported that the 2025 search found 45 scallops in three different search areas after volunteers had found over 260 the year before. The 2026 search tallied 38, according to the Tampa Bay Watch scoreboard posted after the August 1 event. Set against the 2009 record, the recent Tampa Bay figures show scallops present but not yet established in large numbers.

The Tampa Bay Estuary Program turns these numbers into a public record. Its interactive scallop search dashboard shows results for each year of the search and a summary of trends over time, and TBEP uses the data to report scallop abundance against its management plan goals for Tampa Bay.

Scallops are demanding animals. TBEP describes them as a key indicator of Tampa Bay health because they require clear, salty water and robust seagrass habitat. As filter feeders they remove algae and organic matter from the water, and during red tide they take up algae cells and store toxins in their gut. Tampa Bay Watch notes that an adult bay scallop can filter as much as 14.7 liters of water per hour, more than 90 gallons a day.

Their biology also makes the Tampa Bay counts jumpy. Tampa Bay Watch reports that bay scallops grow to about two inches, carry rows of tiny blue eyes along the shell edge, and live only 12 to 18 months. A single scallop releases around 12 million eggs, yet perhaps only one survives to adulthood, so one bad season of red tide, heavy rain or storms can erase much of a local population in a single year.

Yes, more than once. The FWC Fish and Wildlife Research Institute reports that a restoration project from 2002 to 2005 added Tampa and Sarasota bays to earlier work on the Gulf coast north of Tampa Bay. Researchers used juvenile bay scallops raised by a University of South Florida hatchery or by Bay Shellfish Co., planted them in wire cages anchored to the seafloor and checked them monthly. Because cages were costly, FWRI later shifted to larval releases, and since 2005 restoration programs have relied on an aquaculture facility in Palmetto to raise larvae to the stage at which they settle on seagrass blades.

A later pilot focused on Tampa Bay alone. The NOAA Restoration Center project database lists a Tampa Bay Scallop Restoration Strategy project, sited near Tierra Verde with a 2010 construction start, that released larvae at three size classes to find the best size for survival. The project was unable to achieve sufficient results to compare methods, but NOAA records that it pointed to the need for more frequent assessments of adult populations in Tampa Bay.

No open season covers Tampa Bay. Under FWC recreational rules, bay scallops may only be harvested in state waters from a list of zones running from St. Joseph Bay south to the Pasco Zone, and the southernmost of these ends north of Anclote Key Lighthouse in northern Pinellas County. Tampa Bay, Boca Ciega Bay and the Hillsborough County shoreline lie south of that line, so the scallops counted in the Great Bay Scallop Search are watched rather than taken. In 2026 FWC also temporarily closed the Pasco Zone effective August 6.