Category Archives: Notes from the Field

Assessing the Impacts of Hurricane Irma

By Dr. Ryan P. Moyer

The Coastal Wetlands research group at the Florida Fish and Wildlife Research Institute (FWRI) received a grant from the National Fish and Wildlife Federation (NFWF) to assess the impacts of Hurricane Irma to coastal wetland habitats of southwest Florida. Since 2014, the FWRI Coastal Wetlands group along with partner organizations, has been working in coastal marshes and mangroves across Southwest Florida, including Tampa Bay, Charlotte Harbor, Ten Thousand Islands, Biscayne Bay, and the lower Florida Keys. All pre-existing field sites were located within 50 km of Hurricane Irma’s eye path, with a few sites in the lower Florida Keys and Naples/Ten Thousand Islands region suffering direct eyewall hits. Since all locations include active field sites, a wealth of pre-storm data exists, and these locations are uniquely positioned to evaluate and quantify post-hurricane damage to standing biomass and ecosystem services across a wide geographic area.

Map showing the location of field sites in proximity to the path of Hurricane Irma. Pre-existing study sites are given for each area in the inset boxes at right.

Initial Post-Irma field assessments focused on qualitatively assessing and photographically documenting damage (e.g. defoliation, downed trees, redistribution of sediments, etc.). Upon identification of the habitats that experienced the most damage, storm impacts were then categorized as low-, moderate-, and severe-impacts based upon physical habitat damage and distance from eyewall path, height of storm surge, and maximum wind speed experienced during the hurricane. Quantification and monitoring of aboveground damage included measurements of indicators of defoliation (canopy coverage), mortality (recently felled trees and branches), plant community structure (tree diameter or height), and recovery (seedling percent coverage or density). Recovery of mangrove forest was assessed by subsequent visits to long-term monitoring plots in the six months following Hurricane Irma. Sedimentary impacts were also examined and included elevation change, shoreline erosion, and geochemical characterization of storm-derived sedimentary deposits.

Example of severe damage to a mangrove forest in the Ten Thousand Island due to Hurricane Irma. This site was directly under Irma’s eye path as Category 3 storm and was found to have complete loss of leaves in the canopy (defoliation) and numerous downed trees. Canopy cover is typically 80-100% in non-impacted forests.

Preliminary findings indicate a reduction in mangrove canopy cover from 70-90% pre-storm, to 30-50% post-Irma, and a reduction in tree height of approximately 1.2 m. Although signs of forest recovery and shows signs of slow regrowth, mangrove seedling density has significantly increased in the six months post-Irma. A sedimentary layer of fine carbonate mud up to 10-cm thick was imported into the mangroves of the lower Florida Keys, Biscayne Bay, and the Ten Thousand Islands. A siliciclastic mud layer up to 5-cm thick was observed in the marshes of Charlotte Harbor. All sites had imported tidal wrack consisting of a mixed seagrass and mangrove leaf litter, with some deposits as thick as 6 cm. In areas with newly opened canopy, a microbial layer was coating the surface of the imported wrack layer. Overwash and shoreline erosion were also documented at two sites in the lower Keys and Biscayne Bay and will be monitored for change and recovery over the next few years, pending subsequent funding. Due to changes in intensity along the storm path, direct comparisons of damage metrics can be made to environmental setting, wind speed, storm surge, and distance to eyewall. This information will help provide direct evidence of hurricane impact and recovery trajectories in coastal wetland ecosystems in Florida. The data will be shared with coastal ecosystem managers in order to enhance management and response planning for large natural disasters in Florida such as hurricanes.

Project partners included the U.S. Geological Survey, University of South Florida Saint Petersburg, Rutgers University, Nanyang Technical University, the University of Rhode Island, Tufts University, University of South Florida College of Marine Science, and the US National Park Service.

Effects of the 36-year closure and opening of Joe Bay on fishes and recreational fisheries

By Kerry Flaherty-Walia and John Davis

Major portions of the coastal embayments in northeastern Florida Bay have been closed to public access, and thus to recreational fishing, since the creation of the Crocodile Sanctuary in 1980. The 2015 Everglades National Park (ENP) General Management Plan called for the opening of Joe Bay, which is part of the Crocodile Sanctuary, to public, non-motorized access and catch-and-release fishing. The Fish and Wildlife’s Research Institute’s Fisheries Biology and Fisheries-Independent Monitoring (FIM) programs are involved in a cooperative study with Florida International University, the Snook and Gamefish Foundation, the Audubon Society, and the National Park Service to examine the effects of the 36-year closure and subsequent opening of Joe Bay to catch-and-release fishing.

Locations of Little Madeira Bay, Joe Bay and Long Sound in Florida Bay.

To examine the effects of the closure on fish and macroinvertebrate (nekton) community metrics and recreationally important fish species, fisheries-independent and -dependent sampling methods are being employed across three embayments from 2016-2019 (Figure 1). Two of the embayments are in the Crocodile Sanctuary; Little Madeira Bay has been and will remain closed to fishing while Joe Bay was opened to fishing in November 2016. A third embayment, Long Sound, is not in the sanctuary and has been open to fishing the entire time.  Although the three coastal embayments appear similar in size and function, there are substantial environmental differences among the basins. Freshwater inflow into Joe Bay is much greater than the other two basins, and sediment depth and the amount of submerged aquatic vegetation (SAV) are quite low. Long Sound also has a very thin sediment layer but typically had the highest salinity, and in recent years, has experienced an increase in SAV cover. Little Madeira Bay has both a thick sediment layer and a consistently high percentage of SAV cover that includes Thalassia, indicative of a climax seagrass community. These existing spatial and habitat relationships will affect the prey base and recreational fishes and will be considered in assessing the effectiveness of the new management strategy.

Fisheries-independent surveys are being conducted during wet and dry seasons by FWC using small (21.3-m) and large (183-m) seines and by FIU using baited remote underwater video systems (BRUVs) using GoPro technology (Figure 2). In the first year of seine sampling, nekton communities differed significantly among basins; relative abundance of nekton was greatest in Little Madeira Bay, and the most numerous species were small-bodied fish that serve as the prey base, such as killifishes, mojarras, gobies, and schooling fish (silversides and anchovies), collected by the small seine. Unfortunately, the large seine technique (which collected the majority of recreationally important species) was only used in Long Sound and Little Madeira Bay because the depths and substrate in Joe Bay are not suitable to this sampling gear. The BRUVs, however, were deployed in all basins, and in contrast to the seine sampling, indicated that community composition was similar across basins.  Recreationally important species were most frequently observed in Little Madeira Bay in seines, but in Joe Bay on BRUVs. Sharks were seen frequently on video in Little Madeira Bay and may be affecting BRUV observations there. Trophic groups (small prey, large prey, mesoconsumers, and top predators) appeared stable over time as compared to previously collected seine data using the same methodology from 2006-2009, but there was preliminary evidence of species-specific differences within basins and over time.

Three methods are used to determine the effects of the fishing closure: A. BRUVs, B. Seines, C. Angler Reporting System.

Fisheries-dependent information is being obtained through an angler reporting system developed in conjunction with FIU, the Snook and Gamefish Association, and the Audubon Society (Figure 2, paper surveys and a mobile application). So far, the angler reporting system has a good response rate, but visitation to the recently opened no-motor zone in Joe Bay was low.

Two more years of sampling are ahead for this project, so more comprehensive data analyses incorporating hydrological and habitat dependencies are planned.  Seine and BRUV nekton community data will be compared between gears and across estuaries, and the long-term trends in visitation and angler experiences documented by the angler reporting system will be examined. This project will provide useful data for developing a long-term protocol for fisheries monitoring in these embayments into the future and demonstrates the advantage of collaborative research to reach a common goal.

Long Distance Movements by Female Bears

By Walter McCown

FWRI bear researchers began efforts to develop a demographic profile of bears in the Apalachicola subpopulation in May 2016.  We have, thus far, placed Iridium satellite collars on 37 adult female bears to document survival rates, the age of first reproduction, the number of cubs produced, and the interval between litters.  Additionally, each spring we place VHF collars on cubs in the den and monitor them several times a week to document their survival rate.  While these demographic profiles will enable us to construct a population model useful for the management of this subpopulation of bears, the presence of a satellite collar programmed to acquire locations every two hours affords us interesting insights into these bears.

One intriguing aspect of bear behavior occurs during the fall when bears increase their normal food intake from about 8,000 calories (kcal) per day to approximately 20,000 calories per day, resulting in an increase of their body weight by approximately 1.5 kg per day.  This behavior, known as hyperphagia, creates stores of energy in the form of fat and is an adaptation by bears to the lack of food during the winter.  Because bear foods are normally isolated in time and by space, bears may wander widely in the fall and spend up to 20 hours per day eating.  Although the list of food items consumed by Florida bears is rather lengthy (over 100 items) and diverse (bromeliads to walking sticks), acorns and palmetto berries are dominant fall food items in most subpopulations.  When these food items are abundant bears do well and have smaller home ranges.  When these items are more scarce, bears must make greater movements to obtain the calories necessary to survive the winter.

In fall 2016 we noted movements of several bears of 20-30 km into remnants of coastal scrub habitat where they fed on acorns.  In fall 2017, when acorns were apparently not as abundant, bears moved similar distances but further inland to forage in stands of hardwoods along area creeks and rivers.

Interestingly, in fall 2017, bear F605 moved from her home range in Tate’s Hell State Forest near Carrabelle, to private land near Hosford, Florida.  This 12-year-old female accomplished this trek of approximately 58 km (as the crow flies) with her three 8-month-old cubs in only three days (see top photo).  Subsequently, she remained near Hosford all winter, did not make any more noteworthy movements, and successfully raised all three cubs (see map below).

Locations of female bear F605 and three cubs October 17-19, 2017 (click to enlarge).

Bear researchers are frequently impressed with how black bears adapt to their environment and changing conditions.  However, we are bewildered with their ability to somehow know that conditions in distant locations are superior to those in their current use area.  Yet, it is abundantly apparent they do know.  In previous studies, Florida researchers noted lengthy fall movements by bears in Big Cypress during an apparent palmetto berry failure and in Ocala when a drought caused both oak and palmetto fruit production to fail.  Nonetheless, the trek by F605 that we documented was an impressive one for a female with three cubs.

Songbirds in the Salt Marsh: Living on the Edge

By Amy Schwarzer

Two subspecies of little brown songbirds, the Worthington’s marsh wren (Cistothorus palustris griseus) and the MacGillivray’s seaside sparrow (Ammodramus maritimus macgillivraii), call the salt marshes of northeast Florida home. Both subspecies are salt marsh obligates, confined to the marshes near the mouths of the region’s rivers. These birds, which used to range from the state line to Volusia County, have seen their distributions contract until the most recent surveys in 2000-2001 only found breeding individuals north of the St. John’s River. The range contractions led to a state listing of Threatened for the Worthington’s marsh wren, while the MacGillivray’s seaside sparrow has been petitioned for federal listing.

In 2014-15 we conducted point counts both north and south of the St. John’s River to estimate occupancy rates and abundances of both species. We found no signs of repatriation into the previously abandoned southern areas, but no further range contractions north of the river. Both species preferred higher elevation patches in the saltier smooth cordgrass marshes over the neighboring brackish black needle rush marshes, and had increased occupancy rates and abundances farther from upland edges.

From 2015-2017, we monitored 996 wren nests and 123 sparrow nests at seven study plots to determine which habitat and nest features affected nest survival rates.  Study plots were picked based on our point count data and represented high, medium, and low densities of wrens and sparrows. Most singing male sparrows appeared to be unpaired at all but one site, which suggests that there is a sex ratio imbalance in the region. Both wrens and sparrows experienced high rates of nest loss, with evidence pointing to predation as the main cause. Yet daily high tide height most strongly predicted the probability of nest failure for both species, though we saw limited evidence of nest flooding for sparrows and even less for wrens, which nest comparatively higher off the ground in taller grasses.  It may be that extreme high tides concentrate predators in the higher elevation areas of the marsh where the birds tend to nest.

In the last component of our study, we radio-tagged and tracked 50 wren fledglings to look at post-fledging survival. Post-fledging survival was also low compared to similar songbird species, though fledglings that were heavier at the time of tagging survived much better than lighter birds.  The causes of fledgling mortality are unknown, but we confirmed at least one predation event when we tracked one of our transmitters to the belly of a corn snake!

Though analyses of the project’s data are on-going, it has become increasingly clear that these subspecies have a tenuous grasp on survival in northeast Florida, with both low nest survival and low fledgling survival.  While the birds are not yet losing many nests to flooding, they seem sandwiched between the uplands and the rising seas, with high predator concentrations suppressing their reproductive potential.  We intend to synthesize our count and demographic data to identify habitat features that best support wrens and sparrows and to share this information with local managers, hopefully leading to management and restoration efforts that will alleviate some of the pressures these little brown birds face.

Assessing Mercury Concentrations in Alligator Populations

By Alligator Research Staff

The American alligator seems, in some ways, to be one of those perfect species. It has persisted for eight million years with little change. It’s a long-lived (40-60 years) species with high adult survival and a high reproductive potential which helped it recover from once being on the endangered species list. Alligators are also a desired target of hunters for their meat and the value of their hides. And as an apex and keystone species, they play a notable role regulating prey populations and modifying their own environment in ways that benefit other wetland occupants.

Because of their longevity, position in the food chain, and tendency to reside in a limited area, alligators can serve as an indicator of local environmental conditions. Through the process of biomagnification, environmental contaminants can concentrate in their bodies and pose health risks to not only the alligators but also to humans that consume the meat. As a result, FWC’s Alligator Management Program requested that FWRI’s alligator research staff study and monitor mercury (Hg) concentrations in alligator muscle tissue from populations across the state. Our study revealed that average Hg concentrations in Florida waterways varied, but that the rate of accumulation is predictable. Based on these results, alligator research staff began a Hg monitoring program that assesses average Hg concentrations in alligator muscle tissue on harvested lakes, marshes, and river sections known as Alligator Management Units (AMUs). Approximately six or seven AMUs are sampled every year, with a goal of monitoring Hg on over 50 AMUs statewide.

The process involves capturing juvenile (3-6 ft) alligators by hand, snare, or snatch hook, and taking a 0.5-gm biopsy sample of tail muscle tissue to be tested for Hg. The alligator is marked for future identification and released. The tissue samples are sent to the Indian River Field Lab in Melbourne, where our FWRI collaborators analyze them for Hg concentrations. Based on the results and what we learned from the study, we estimate the average Hg concentration of a 7.5-ft alligator (an average-sized alligator that is harvested) on that AMU and inform the Alligator Management staff on whether health/consumption advisories need to be issued.

Advisories are issued to alligator hunters and nuisance trappers that hunt on areas with an average Hg concentration of ≥1 mg/kg. When applied, the advisories prohibit the sale of alligator meat from these areas and strongly discourage consumption. Hunters are, however, allowed to sell the alligator hide. To date, we have identified only two AMUs that meet the criteria for issuing health advisories. Both areas, Water Conservation Areas 1 and 2, are located in South Florida and are part of the eastern Everglades ecosystem. FWRI staff will continue to assess Hg levels in alligator meat to ensure that the public is informed of and protected from any potential health risk.

Meet FWC’s Climate Adaptation Core Team

By Lily Swanbrow Becker

This fall will mark ten years since FWC officially began its work on climate change adaptation by hosting a statewide summit.  Since then, we’ve traveled down a long and winding path.  Our team has gained and lost talented staff along the way but the journey has been a productive one and today we find ourselves with a dedicated, cross-divisional team and a long list of accomplishments.  Previous iterations of the Climate Adaptation Core Team have worked with internal staff and partners to complete climate vulnerability assessments, integrate adaptation into our State Wildlife Action Plan, host training and scenario planning workshops and publish a comprehensive guide to Florida natural resource adaptation, accessible to anyone here, to name a few examples.  These days, our small team is looking to the future and setting a course of priority goals and actions for the next five years.

In the beginning, we focused on laying the groundwork by pursuing critical science to better understand the projected impacts of climate change on Florida fish and wildlife and identifying key vulnerabilities.  We’re now in a great position to continue building on this knowledge and technical capacity by helping to coordinate and strengthen research and monitoring programs, leveraging funding opportunities and developing a data sharing platform to support and coordinate the important research FWC staff and partners are doing.  However, as we set our sights on the end goal of integrating climate adaptation throughout the agency and implementing meaningful on-the-ground adaptations actions, we are increasingly focusing on the importance of communicating effectively and building internal capacity and community.

One of the first steps in that process is the very intent of this brief update: we’d like to let you know we’re here!  Our team recently began an internship program based out of Tallahassee and our new climate adaptation interns have done an excellent job launching a monthly newsletter.  If you’d like to stay updated on climate-related funding opportunities, events, resources, publications and more, please send a brief email to Lily, mentioning that you’d like to subscribe.  As we continue moving toward finalizing our five-year goals and work plan this spring, we’ll be adding more content to our team SharePoint site, which you’re always welcome to explore.  And finally, if you’re already working on a climate-related topic and you’re not connected with our team, we’d love to hear from you.  We’ll have many opportunities for collaboration in the days ahead and we hope to make as many connections throughout FWRI as possible, as we carry forward working on this pressing issue.

Current Climate Adaptation Core Team Members: René Baumstark (FWRI), Brian Branciforte (HSC), Terry Doonan (HSC), Bob Glazer (FWRI), Beth Stys (FWRI), Lily Swanbrow Becker (HSC/FWRI)

A Light in the Fog: Shipboard Genetic Quantification of the Red Tide Alga Karenia brevis

By Alicia Hoeglund, Matt Garrett and Mary Harper

On January 11, on FIO’s new research vessel (R/V) the W. T. Hogarth, FWRI-HAB researchers assisted USF in deploying new infrastructure for oceanographic sensors and took advantage of this opportunity to test hand-held genetic sensors that can detect the red tide alga, Karenia brevis, in water samples collected while onboard. The genetic detection project, funded through a NOAA Prevention Control and Mitigation of HABs (PCMHAB) grant, utilizes a field-friendly approach that can provide genetic quantification of K. brevis in approximately one to three hours from the time of sample collection (see: http://fwcfieldnotes.com/2016/12/on-site-testing-for-red-tide-alga/). Samples collected just west of the Skyway Bridge and off of Pass-a-Grille (Pinellas County) were tested during this trip and provided our researchers with some of the lowest field concentrations of K. brevis observed with this technology to date: approximately 108 cells L-1 and 42 cells L-1, respectively. The limit of detection using our routine light microscopy procedure is 333 cells L-1, making this a very promising find for the development of this project!

Syringes funnel the sampled water into a column that contains the filter to which the RNA binds.

Although this was intended to be a short-day trip, thick sea fog delayed both the departure and the return of the R/V W.T. Hogarth, with researchers spending an unanticipated night at sea. A short reprieve from foggy conditions allowed the port to reopen briefly early in the morning of the 12th, and sea fog continued to impact the area throughout that day. A subsequent trip completed the installation of USF’s oceanographic sensor system, and water current, meteorological, and wave data are now being reported every one to three hours (http://www.ndbc.noaa.gov/).

Deployment of the real-time waves system and meteorological sensor: Once the concrete bottom mount and the Acoustic Doppler Current Profiler was dropped in the water by the ship’s crane, divers descended to remove the deploy cables and ensure the instrument was in the proper location and orientation.

Living Shoreline Suitability Model for Tampa Bay: A GIS Approach

By Chris Boland

Because of the threat of shoreline erosion from strong storm action and sea level rise affecting waterfront property values, considerable attention has been focused on shoreline protection.  In the recent past, shorelines have been “stabilized with hardened structures, such as bulkheads, revetments, and concrete seawalls.  Ironically, these structures often increase the rate of coastal erosion, remove the ability of the shoreline to carry out natural processes, and provide little habitat for estuarine species.”[1]  Alternatively, government agencies responsible for resource protection have proposed more natural bank stabilization and erosion control called “living shorelines,” which NOAA defines as: “… a range of shoreline stabilization techniques along estuarine coasts, bays, sheltered coastlines, and tributaries… [that]… incorporates [natural] vegetation or other living, natural ‘soft’ elements alone or in combination with some type of harder shoreline structure (e.g. oyster reefs or rock sills) for added stability… [to] maintain continuity of the natural land-water interface and reduce erosion while providing habitat value and enhancing coastal resilience.”[2]

Figure 1

FWRI’s Center for Spatial Analysis (CSA) has taken an interest in living shorelines in the Tampa Bay region and, as a state partner in the Gulf of Mexico Alliance (GOMA), became aware of the Virginia Institute of Marine Science’s (VIMS) Living Shoreline Suitability Model (LSSM)[3] and its application in Mobile Bay, Alabama.[4]  VIMS developed the LSSM in ESRI’s ArcGIS Model Builder based on a decision tree that can assist in identifying appropriate living shoreline treatments to an area (Figure 1).  Because of the LSSM’s success in identifying locations where a living shoreline restoration project may be effective, CSA’s Kathleen O’Keife and Chris Boland received grant funding from GOMA’s Habitat Resources Team (HRT) to apply the LSSM to the Tampa Bay region.

The LSSM requires information about existing environmental conditions to correctly apply the decision tree, such as existing habitat, slope of coastal waters, environmental conditions (e.g. fetch, current speed, and sunlight shading), and potential construction barriers (e.g. nearby road or permanent structures).  The recently updated (June 2016) environmental sensitivity index (ESI) dataset, originally collected for oil spill response purposes, answered many of these required criteria and so became CSA’s base input dataset to the model.  CSA staff spent approximately four months of full-time work to manually review each of the 5,162 shoreline segments, which ranged in length from about 100 feet to about 500 feet and classified the remaining required data fields appropriately.

Once completed, the LSSM model was run based upon the derived input dataset and completed in less than an hour.  The model outputs resulted in additional fields that provide property owners and management entities with suggested Upland Best Management Practices (BMP) and Shoreline BMPs. [5]  The results are displayed in Figures 2 and 3.  Overall, the modified LSSM recommended the installation of a living shoreline to approximately 33% of the shoreline, protection from a “harder” landscape protection method to about 11% of the shoreline, and was unable to recommend a BMP to the rest (56%) Tampa Bay area’s shoreline, typically because the installation of a living shoreline would be obstructed by an existing shoreline condition.

Figure 2
Figure 3

The model results can be reviewed in CSA’s educational materials that were developed as grant deliverables.  The ArcGIS Online story map (http://arcg.is/0CPKD9) was developed to inform the general public of the use of living shorelines as a shoreline protection alternative, and the Web Mapping Application (http://arcg.is/2gr3Fca) was intended to assisting managers in identifying potential preservation and mitigation areas.

[1] (National Oceanic and Atmospheric Administration, n.d.)

[2] (National Oceanic and Atmospheric Administration (NOAA), 2015)

[3] (College of William and Mary: Virginia Institute Of Marine Science: Center for Coastal Resource Management, 2018)

[4] (Woodrey, 2016)

[5] (VIMS: Center for Coastal Resource Management Program, 2015)

 

Scallop Restoration in the Florida Panhandle

By Jennifer Granneman

Bay scallops (Argopecten irradians) may have a short life, typically living for about a year, but they play a big role in the economies of many coastal Floridian towns, like Steinhatchee and Port St. Joe.  In 2016, the scallop team within the molluscan fisheries group began a 10-year project to restore bay scallops to self-sustaining levels in Florida’s Panhandle.  The project is funded by restoration money set aside after the Deepwater Horizon oil spill and is intended to increase recreational fishing opportunities in the Florida Panhandle.  The goal of the project is to increase depleted scallop populations and reintroduce scallops in suitable areas from which scallops have disappeared.

Restoration efforts are focused on coastal estuaries within the Florida Panhandle that have been divided into five regions, as shown on the map.  Bay scallop populations in the Florida Panhandle are currently classified as ‘collapsed’ with population densities below 0.01 scallops per m2.  In St. Joseph Bay, this collapse may be due in part to a red tide event that occurred from winter 2015-spring 2016.  The red tide resulted in a lack of recruitment in 2016, leading to a sharp population decline.  Scallop restoration efforts were primarily focused on St. Joseph Bay in 2016-2017.  This year, restoration efforts will expand to St. Andrew Bay and St. George (regions 3 and 5).

The scallop team is planning to use a three-step approach to enhance bay scallop populations within targeted restoration areas in the Florida Panhandle by: (1) installing cages holding groups of adult bay scallops, (2) releasing hatchery-reared or naturally-harvested juvenile bay scallops (spat) at restoration sites, and (3) releasing hatchery-reared bay scallop larvae.  Each year, the scallop team collects adult scallops from St. Joseph Bay and brings them to a hatchery which provides juvenile scallops the following year.  These hatchery scallops are then placed in cages in a no-entry zone in St. Joseph Bay.  Placing scallops in cages protects them from predators and increases the likelihood that scallops will successfully produce offspring during the spawning season.  Beginning in 2017, scallop collectors were placed in St. Joseph Bay and St. Andrew Bay to collect wild scallop spat.  The spat are raised at the Florida State University Coastal and Marine Laboratory and once they reach a size of 30mm they will be planted in cages in their respective bays.  Last year we placed 2,500 wild and hatchery-produced scallops in cages in St. Joseph Bay.

In addition to traditional approaches to restoration, our vision for restoring scallops also includes educating the public about our ongoing restoration projects and asking them to be contributing partners in these efforts.  To that end, we have recruited 200 volunteers to help restore scallops in St. Joseph Bay and St. Andrew Bay.  In April, we will provide scallops and predator exclusion cages to these volunteers at workshops held in Panama City and Port St. Joe which will be hosted by our partners at Sea Grant.  Our volunteers, or ‘Scallop Sitters’, will place their cages with scallops off privately-owned docks, or, if they have a boat, they will place these cages in the bay.  We will give a webinar to discuss this project and provide training for our ‘Scallop Sitters’ through the FWC webinar series on April 16.  Volunteers that are unable to attend our workshops in April will be able to view this webinar and participate in our scallop restoration program. We hope that by partnering with the community we will increase our chances of successful restoring scallops to stable levels (>0.1 scallops/m2) in St. Joseph Bay and St. Andrew Bay.  If you have questions about the program or want to get involved, please email us at bayscallops@myfwc.com.

If you would like more information about this restoration program, check out these links: http://myfwc.com/research/saltwater/mollusc/bay-scallops/restoration/current-projects/

http://myfwc.com/research/saltwater/mollusc/bay-scallops/restoration/help-restore/

FWC promotional video: https://www.youtube.com/watch?v=kBC478TnbWc

Panhandle outdoor show: https://www.youtube.com/watch?v=uiFhbA7KONU

Apple Snails and Snail Kites

By Jenn Bernatis, Ph.D.

Changes in Florida’s freshwater ecosystems over the decades have had a myriad of impacts on native species. Now, we are looking at the possibility of relying on an invasive snail, Pomacea maculata, to support the federally listed Snail Kite (Rostrhamus sociabilis plumbeus). Snail Kites feed almost exclusively on Apple Snails, but population declines in the native Florida Apple Snail (Pomacea paludosa) appear to be occurring in traditional kite nesting areas. Over the last 12 years, the invasive P. maculata (Island Apple Snail) has spread throughout the state becoming an alternate food source in many systems where Snail Kites nest. Many of these nesting sites are manipulated for a variety of reasons, yet definitive impacts on the snails and birds remains uncertain.

East Lake Tohopekaliga is a nesting site for Snail Kites and home to both the Florida Apple Snail and Island Apple Snail. The lake is slated for an extensive restoration including draw-down, scraping and removal of sediment, and vegetation treatments. This system has provided state and federal researchers with the opportunity to monitor both snail and bird activity pre-restoration, during restoration, and post-restoration. The data collected during this period will provide much-needed data that can be used in determining future restoration activities at sites with Apple Snails.

At this time four sampling events, two summer and two winter, have been conducted. These sampling events use a combination of throw traps, transects, wading, snorkeling, and scuba diving to locate snails. More than 800 sites have been sampled around the lake ranging from 0.25 m to 2.25 m deep. More than half of the snails collected have been in depths greater than 0.75 m. The majority of the sites with snails have some sort of vegetation, either emergent or submersed, but a few snails have been collected at sites with no vegetation. More snails have been collected in the summer, as this is also peak reproductive period than in the winter. This finding demonstrates conclusively that snails utilize deeper water and that Apple Snail surveys need to focus on a range of depths and not just the shallow marsh areas.

Tracking the snails long term will provide information critical to dealing with Apple Snail populations. Although invasive Apple Snails are economically and potentially ecologically damaging, they are serving a critical role as a food source for the Snail Kite. Understanding the movement patterns and use of the water column by Apple Snails will allow managers to better anticipate the impacts on Snail Kites and adjust management plans accordingly. Likewise, the research will provide information that may be of use in developing snail eradication programs. Previous tactics have included draw-downs in an attempt to kill the snails through desiccation. This is not an applicable approach as it is known that invasive Apple Snails can survive out of the water for at least a year. The question that will be answered is, “Are the snails burying?” which they are capable of, or “Are the snails following the water?” at which point the draw-down will have minimal impacts on Apple Snails. If the snails bury, and scraping is part of the proposed activity, then reintroducing the Apple Snails, preferably the native, may need to be considered in locations with Snail Kite nesting history. Ultimately, this study will fill in missing data gaps on snail ecology and provide necessary information when working with systems with Apple Snails and particularly those with Snail Kites.