FW-3
Support Bay Scallop Restoration
Objectives: Achieve a stable, sustainable population of bay scallops in Tampa Bay.
STATUS:
Ongoing. Goal revised to reflect need to achieve sustainable scallop population rather than
population sufficient for recreational harvest. Action also revised to identify additional living
resource indicators of seagrass health. Action continues support for collaborative research and
scallop restoration, and support for citizen monitoring through the Great Bay Scallop.
BACKGROUND:
The goal of restoring scallops to sufficient numbers to support a recreational harvest in Tampa
Bay remains as elusive as the secretive bivalves themselves. Despite dramatically improved
water quality, expanding seagrasses, and nearly two decades of research and recovery efforts,
scallops in Tampa Bay have not yet returned to healthy, sustainable levels.
Scallops are a key indicator of the bay’s health because of their reliance on clear waters and
robust seagrasses. They also are a popular and tasty treat enjoyed by thousands of Floridians
each year in nearshore waters north of Pasco County where scallop harvests are permitted. As
such, they are a cherished symbol of summertime fun in our state.
Scallops disappeared from Tampa Bay in the 1960s, a likely casualty of both declining water
quality and overfishing. Efforts to “jump-start” scallops began in the mid-1990s, including
rearing them in hatcheries and releasing them in protected cages to spawn in the bay.
Recreational harvests remain closed.
In 1996, the Estuary Program and Tampa BayWatch partnered to create the Great Bay Scallop
Search, a one-day event that enlists volunteers to snorkel grass beds in the lower bay looking for
scallops. The Scallop Search was halted when the number of scallops dipped to zero over time,
but was revived in 2004 as observations of scallops in the bay rose again.
In 2007, Scallop Search volunteers tallied 555 scallops during the event, followed by 624 in
2008 and a record 674 in 2009. These positive tallies fueled continued research and monitoring
efforts. However, in 2010 scallop counts dropped again, to 32, then to five in 2011. The most
recent Scallop Search, in 2014, documented 51 scallops.
Bay scallops are extremely sensitive to changes in water clarity, salinity and temperatures. Their
limited life span of approximately one year complicates efforts to revive populations in the bay.
Additionally, only one egg out of millions produced by a single adult scallop may survive.
Moreover, new research indicates that the success of scallop recruitment here may depend upon
successful dispersal of larvae from important “source sites” in the Big Bend area of Florida,
where scallops are most abundant, but harvest pressure is intense.
Ocean acidification associated with climate change also may affect the future health of bay
scallops and other mollusks by impairing their ability to form hard, calcified shells.
Scientists continue to survey scallop populations in Tampa Bay as part of a coordinated
monitoring effort throughout Southwest Florida, and to investigate innovative ways to improve
spawning success and larval survival. A new approach from scientists with the Sarasota Bay
Estuary Program and the Florida Fish and Wildlife Conservation Commission releases hatcheryreared scallop larvae into seagrass beds just before they transform into tiny immature scallops
called “spat” that attach to seagrass blades. The larvae are confined in temporary enclosures so
their survival and growth rates can be monitored.
In the next decade, it is unlikely that scallop populations in Tampa Bay will rebound to levels
sufficient to support a recreational harvest season. Therefore, this action proposes a revised goal
of restoring scallop stocks to a self-sustaining level, with enough adults surviving to spawn each
year to create a stable population so larval seeding efforts may one day no longer be necessary.
This action also supports continuing the popular Great Bay Scallop Search, as both a costeffective monitoring tool and an outstanding educational vehicle for “immersing” and involving
citizens of all ages in bay restoration.
STRATEGY:
Activity 1
Continue to implement Action WQ-1, the Nitrogen Management Strategy for
Tampa Bay, to ensure sufficient water quality and seagrasses to foster scallop
recovery.
Responsible Parties: TBEP, All members of the Tampa Bay Nitrogen
Management Consortium (NMC)
Timeframe: “Reasonable Assurance” documentation of reductions in
nitrogen loadings and water quality monitoring to be submitted in 2017,
and every five years after that, as required by the Florida Department of
Environmental Protection.
Cost and potential funding sources: $$$ CWA Section 320; NMC dues
paid annually by all Consortium members
Location: Baywide
Benefit/Performance measure: Water clarity and nitrogen reduction
goals being met
Results: Reduction of nitrogen loadings and resulting water clarity
sufficient to support seagrasses essential for scallops to thrive in Tampa
Bay.
Deliverables:
 “Reasonable Assurance” document summarizing progress in
achieving/maintaining nitrogen reductions goals for each bay
segment.
 Annual water quality summary (the “Decision Matrix”) for five
major bay segments, based on adopted segment-specific water
clarity targets. This report utilizes data collected by the
Environmental Protection Commission of Hillsborough County.
Activity 2
Continue participation in collaborative research, monitoring and restocking efforts
in Tampa Bay and other SW Florida estuaries. Develop a methodology for
determining spawning and recruitment needs to establish a self-sustaining
population in the bay.
Responsible Parties: TBEP, SBEP, CHNEP, FWC, Mote Marine
Laboratory, Tampa Bay Watch, other members of the SW Florida Scallop
Restoration Working Group
Timeframe: Ongoing. Development of methods and benchmarks for
sustainable scallop populations to begin in 2016.
Cost and potential funding sources: $ CWA Section 320 funds; potential
external grant funds
Location: Collaborative effort throughout SW Florida, including Tampa
Bay, Sarasota Bay and Charlotte Harbor
Benefit/Performance Measure: Requirements for self-sustaining
population of bay scallops in Tampa Bay defined.
Results: Stable, sustainable population of bay scallops in Tampa Bay and
other estuaries throughout SW Florida.
Deliverables:
 Methodology for determining sustainable population of bay
scallops (SW Florida Scallop Restoration Working Group)
 Recommendations for achieving a stable population, including
additional research and monitoring needs, and restocking efforts.
(SW Florida Scallop Restoration Working Group)
Activity 3
Continue to conduct the Great Bay Scallop Search to foster citizen awareness of
the bay’s value and to support monitoring to determine viable, sustainable
populations in the bay once benchmarks are established.
Responsible Parties: Tampa Bay Watch, TBEP
Timeframe: Scallop Search conducted annually, usually in August
Cost and potential funding sources: $ CWA Section 320 funds
Location: Lower Tampa Bay (specifically waters in and around Fort De
Soto Park)
Benefit/Performance Measure: Participation of 150 citizens in
monitoring boosts public appreciation of bay’s value and contributes to
scientific understanding of scallops in Tampa Bay.
Results: Annual estimate of scallop abundance helpful to identify longterm trends in scallop recovery.
Deliverables:
 Report summarizing abundance and distribution of scallops in
Scallop Search monitoring area. (Tampa Bay Watch)
Activity 4
Identify appropriate additional living resource indicators, such as pink shrimp or
spotted sea trout, that are less vulnerable to extreme yearly fluctuations. These
species may provide a more comprehensive and accurate long-term portrait of bay
health.
Responsible Parties: TBEP, FWC-FWRI
Timeframe: Identification and assessment of additional suitable indicators
in 2017.
Cost and potential funding sources: $ CWA Section 320 funds
Benefit/Performance measure: Selection and adoption of monitoring
protocols for one or more additional living resources indicators
Results: Use of more predictable living resource indicators provides a
more comprehensive assessment of bay health.
Deliverable:
 Report assessing viability and relative merits of additional living
resource indicators (TBEP)
 Monitoring reports incorporating status of selected indicators
(possibly FWC, depending on species selected)
Accomplishments for FW-3
1996-2006
Action Title: Support bay scallop restoration.
TBEP played a role in the following:
 Created the Great Bay Scallop Search, in partnership with Tampa Bay Watch, to enlist
citizen scientists in tracking scallop populations during an annual volunteer event. TBEP
scientists and partners developed the scientific methods for collecting scallop data at
random sites in portions of Lower Tampa Bay where scallops are most often found.
 Partnered on and funded the Great Bay Scallop Search during years with active scallop
populations during this period.
 Monitored scallop re-stocking efforts conducted by the Fish and Wildlife Research
Institute, Tampa Bay Watch and University of South Florida involving transplanting
scallops to areas with adequate scallop habitat.
 Implemented the Nitrogen Management Strategy for Tampa Bay, Action WQ-1, to
ensure sufficient water quality and seagrasses to foster scallop recovery.
2006-2016
Action Title: Support bay scallop restoration.
TBEP played a role in the following:
 Continued financial and staff support of the Great Bay Scallop Search volunteer effort to
track scallop populations in Lower Tampa Bay.
 Awarded Bay Mini Grant funds to facilitate the release of an unprecedented large number
of scallops into Lower Tampa Bay. This project partnered a local neighborhood
association with scientists from the Florida Fish and Wildlife Research Institute to release
hatchery-reared scallop larvae into seagrass beds to stimulate local populations and
monitor through survey counts.
 Continued implementation of the Nitrogen Management Strategy for Tampa Bay, Action
WQ-1, to ensure sufficient water quality and seagrasses to foster scallop recovery.