Category Archives: Notes from the Field

Fish and Wildlife Health Staff Investigate Ulcerative Skin Lesions in Lionfish

By Catalina Brown

In mid-August 2017, the FWC Division of Marine Fisheries Management’s lionfish group contacted the Fish and Wildlife Health Staff to confirm they collected lionfish (invasive Indo-Pacific lionfish Pterois volitans/miles complex) with significant ulcerative skin lesions approximately 30 miles off Pinellas County.

Ulcerated lionfish were also documented offshore Pensacola by local divers on Aug. 5. Following these initial reports, lionfish presenting with ulcers have also been reported in waters of the, East Florida Shelf, the Florida Keys, and the Bahamas as well as throughout the Caribbean Sea, including offshore of the Cayman Islands, Bonaire and Belize. FWC’s Fish and Wildlife Health group are collaborating with UF and Okaloosa County to obtain specimens and conduct necropsies to determine the etiology of the disease. In conjunction with UF, FWC have evaluated the specimens for parasitic infection as well as bacterial, fungal and viral infection.

This ongoing research is critical because the pathogen could be non‐specific and impact other marine sport fish species. Histological analysis has demonstrated tissues that appear to be healing. A causative agent has not been identified, but FWC continue to receive periodic reports of ulcerated fish and try to get specimens for analysis as they become available.

A Fond Farewell to Ed Matheson, FIM’s Top Taxonomist

By Sean Keenan and Theresa Warner, with much assistance from coworkers

Dr. Richard “Ed” Matheson Jr., an Associate Research Scientist at the Fish and Wildlife Research Institute (FWRI), is retiring after 32 years with the Institute. A Masters from the College of William & Mary and a Ph.D. from Texas A&M University provided Ed with the basis for a career focused on the systematics and ecology of fishes. Over the years, his research interests have included Gerreid systematics, seagrass-associated fishes, fishes of tidal-rivers, fish community structure in Florida Bay, seagrass die-offs, Everglades restoration, and fishes of the West Florida Shelf.

Starting with FWRI St. Petersburg in 1987, Ed has seen the Institute transition through several agencies and name changes to become what it is today. Initially hired into the Coastal Zone Management group with the Fish Biology program, Ed became the chief ichthyologist for the Fisheries-Independent Monitoring (FIM) program in the late 1990s. With FIM’s statewide, comprehensive sampling, rare or difficult to identify species are frequently encountered and they invariably come to Ed for verification.

Ed is seen here field sampling in Florida Bay.

The accurate identification of specimens is vital to evaluating distribution and abundance trends of native and exotic species. Ed has been instrumental in developing, maintaining and ensuring the near perfect fish identification proficiency of FWRI staff. He regularly creates and presents fish identification training sessions that focus on key sportfish and difficult to identify species groups like gobies, mojarras and sunfishes. His sessions always include a presentation, access to slides and identification keys, and typically include a ‘hands-on’ component that reinforces what staff learned in the presentation. Ed’s fish identification contributions beyond FWRI have been equally important. He frequently confirms identifications of specimens being cataloged in the Ichthyology Collection of the Florida State Board of Conservation and receives requests for assistance from other groups such as FWC Law Enforcement.

The professional impact of Ed’s work at FWRI is immeasurable. He has been the lead author on five peer-reviewed manuscripts and he has co-authored over 20 manuscripts and over 10 reports. He has served as adjunct faculty at the University of South Florida (USF) and as a graduate committee member for students at USF and the University of Central Florida. Ed has participated in innumerable one day estuarine sampling trips, eight multiday research cruises, and dove in the Johnson Sea-Link submersible to 1,100 feet. He is a member of the American Society of Ichthyologists and Herpetologists, American Fisheries Society and Sigma Xi. Ed has served as a reviewer for scientific journals including Bulletin of Marine Science, Estuaries, Southwestern Naturalist and Fishery Bulletin.

Ed is one of the friendliest and most approachable scientists at FWRI. His sense of humor, pleasant demeanor, and professional expertise have made him an invaluable and irreplaceable asset to FWC.

Best Fishes, Ed! We will miss you.

Sea Turtles and Red Tide

By Allen Foley

Red tide often kills fish, but when the concentration of Karenia brevis reaches around 100,000 cells per liter, it can also kill sea turtles, birds, dolphins and manatees. In Florida, we have been documenting stranded (i.e., dead, sick or injured) sea turtles since 1980. We have documented unusually large numbers of stranded sea turtles coincident with red tides primarily along the Gulf coast (especially in the southwest) but also along a portion of the Atlantic coast (Brevard County). These strandings are typically adult and large immature loggerheads and Kemp’s ridleys, and small immature green turtles and hawksbills. Stranding data modeling and sampling of strandings to determine brevetoxin concentrations all indicate that red tides mostly kill loggerheads and Kemp’s ridleys. There are almost no strandings attributed to red tide during some years but there are many hundreds attributed to red tide during other years.

The latest red tide event began in southwest Florida during November 2017. Since then, we have attributed 589 stranded sea turtles (252 loggerheads, 265 Kemp’s ridleys and 72 green turtles) to that red tide bloom — the largest number of stranded sea turtles we have ever attributed to a red tide. The next largest groups of these stranded sea turtles were documented during 2006 (N = 345), 2003 (N = 230), and 2005 (N = 223).

Recruitment of Juvenile Gag Grouper in the Eastern Gulf of Mexico

By Ted Switzer

Gags (Mycteroperca microlepis) support extensive commercial and recreational fisheries in the eastern Gulf of Mexico. A 2016 stock assessment did not support earlier assessments that indicated that gags are currently overfished and continue to undergo overfishing (South East Data Assessment and Review 33 update). Considering the status of Gag in the eastern Gulf of Mexico, it is especially important to improve understanding of its juvenile recruitment processes.

Study area of polyhaline seagrass habitats sampled in estuarine systems in the panhandle (St. Andrew Bay, Apalachicola Bay), Big Bend region (St. Marks, Econfina, and Steinhatchee), and peninsula (Tampa Bay and Charlotte Harbor) of Florida, USA (Schrandt et al. 2018).

Past research has shown that juvenile Gags generally occupy structured polyhaline (18-30 practical salinity units) habitats such as seagrass beds and oyster reefs for several months before emigrating to nearshore reefs (Figure 1). The reliance of Gags on estuarine nurseries, combined with a brief period of estuarine occupancy, greatly facilitates the accurate characterization of the strength of juvenile recruitment.

A comprehensive examination of long-term (10+ years) FWC/FWRI fisheries-independent data was conducted to characterize habitat selection and recruitment of juvenile Gags. Results from Apalachicola Bay, Tampa Bay and Charlotte Harbor habitat suitability analyses indicated that juvenile Gags selected polyhaline habitats with sloping bottoms and extensive seagrass coverage. These analyses indicated that the near shore, deeper water polyhaline seagrass habitats had been under sampled (Switzer et al. 2012).

A multi-gear survey (183-m haul seine and 6.1-m trawl) was designed to supplement long-term, fisheries-independent survey data on estuarine-dependent reef-associated fishes. The supplemental survey design specifically considered juvenile Gag recruitment ecology and thus targeted the deep, polyhaline (>18 psu) seagrass habitats that are used by age-0 Gags. Potential sampling sites were limited to generally polyhaline waters that contained at least 50% bottom coverage of seagrass, had a measurable slope and were between 1.0 and 7.6 m deep.

Gag begin their life offshore in a pelagic environment where they spend their first 30-60 days. Eventually they settle out onto shallow water seagrass beds, where they spend the summer months feeding and growing. In the fall they migrate to nearshore hard-bottom habitat. As they mature, they eventually migrate to deeper water reefs and as mature adults they form spawning aggregations and spawn during the winter months. Gag are hermaphrodites. They are born as females and as they grow eventually transition to be male.

This supplemental sampling was initiated in 2008 and polyhaline seagrass beds were sampled by bottom trawls (6.1-m otter trawl) and haul seines (183-m haul seines) in seven estuaries along Florida’s Gulf coast (Figure 2). Apalachicola Bay, Charlotte Harbor and Tampa Bay have been routinely sampled since the late 1990s; St. Andrew Bay and three estuaries in the Big Bend region between Cedar Key and Cape San Blas (St. Marks, Ecofina, and Steinhatchee), where Gag recruitment had been documented, were added for this study and have become part of the continuing survey.

Analyses of the data collected in the long-term and supplemental surveys (2008-2012) demonstrated the effectiveness of this sampling approach. The size ranges of Gags collected in both studies were similar, but age-0 individuals were captured more frequently and the catch-per-unit-effort (CPUE) was significantly higher in the supplemental surveys (Switzer et al 2015). These analyses will not only enhance our understanding of recruitment processes for juvenile Gags in the eastern Gulf but will also provide valuable insight into observed patterns of habitat use and the relative importance of various habitat types. Nevertheless, additional information on habitat availability, combined with a better understanding of the estuarine systems’ relative contributions to nearshore Gag populations, will be required to maximize the utility of these data in predicting fisheries productivity.

Strong Gag year-classes have been documented as persisting as the fish grow and enter the fishery. Accordingly, accurate estimation and prediction of juvenile recruitment is critical to the effective assessment and management of at-risk fisheries. Variability of estuarine nekton assemblages is valuable as an indicator of environmental quality.  Therefore, the patterns discerned from the supplemental sampling have important implications for fisheries managers.

Monitoring Suburban Florida Sandhill Cranes

By Tim Dellinger

The Florida sandhill crane (Antigone canadensis pratensis) is one of five sandhill crane sub-species found in North America.  Florida sandhills are non-migratory and range from southeastern Georgia to the Everglades.  The current population estimate is around 4,600 birds and it is state-listed as Threatened in Florida.

Like other crane species, Florida sandhills need wetlands as well as uplands.  Wetlands such as shallow depression marshes and lake edges are used for nesting, foraging, and roosting.  Uplands with low vegetation, such as private ranchland and dry prairie, are used for foraging and loafing.  Both habitat types are equally important to cranes.  Unfortunately, wetlands are often drained and open uplands bulldozed to make way for roads, shopping malls, and subdivisions.  Remarkably, however, some cranes are remaining in or moving to urbanized areas and living among us.

Staff banding and tagging a Florida sandhill crane captured in a strip mall parking lot in Seminole County.

In 2017 we began a project examining how Florida sandhills are using urbanized areas.  We are currently tagging adult cranes with cellular GPS transmitters in suburbs and developed areas.  The transmitters collect GPS locations at 30-minute intervals and are uploaded to us daily.  We are also tagging Florida sandhills in rural and conservation areas to help us better understand survivorship, productivity, and habitat use along the urban gradient.

Preliminary data show that some urban cranes solely inhabit suburban or developed areas.  They use suburban yards, grassy roadsides, golf courses, and open areas around colleges and hospitals as uplands, and retention ponds or lake edge for wetlands.  However, most urban cranes regularly moved between rural areas or conservation lands to suburban areas to meet their daily needs.  Preliminary movement data for Florida sandhills tagged on conservation lands show that all individuals use some man-made habitat daily, either a mowed area near a road, a yard with a bird feeder, or improved pastureland. We will continue to tag cranes during 2019.

Diamondback Terrapin Status Assessment

By Traci Castellón

The diamondback terrapin (Malaclemys terrapin) is a once common estuarine turtle that experienced serious declines a century ago and has declined further in recent decades due to numerous pressures including habitat loss and drowning in crab traps. The Florida coastline represents approximately 20% of the species range and is home to five of seven subspecies, three of which occur only in Florida. However, little is known about the status and distribution of diamondback terrapins in Florida.

Ornate diamondback terrapin (M.t. macrospilota)

With funding from a State Wildlife Grant, FWRI is collaborating with partners statewide to conduct a biological status assessment of the diamondback terrapin in Florida. The project includes population assessments in three locations with known terrapin populations (Banana River, Florida Bay and the middle Florida Keys), and, where possible, we are also helping facilitate population assessments and surveys by partners elsewhere in the state.

Another major component of the work is collection of tissue samples from terrapins statewide for a genetic analysis to assess validity of the currently recognized subspecies taxonomy and, where possible, to conduct population-level genetic analyses to assess effective population sizes, gene flow and possible signs of inbreeding depression. Other efforts include gathering and consolidating existing data from partners to update the known distribution of terrapins statewide and using these data to develop a spatial model to quantify habitat availability. Finally, we will estimate the magnitude of past and future population reductions based on historic and projected future habitat losses.

East coast Florida diamondback terrapin (M.T. tequesta)

To date we have developed numerous partnerships, mapped > 5,500 individual sightings, collected > 300 tissue samples for genetic analysis, completed one season of mark-recapture work in the Banana River, and will begin fieldwork in Florida Bay and the Florida Keys in November 2018.

Major partners include Eastern Florida State College; Sanibel-Captiva Conservation Foundation; the US Geological Survey’s Wetland and Aquatic Research Center; University of Florida’s Department of Wildlife Ecology and Conservation, Florida Sea Grant Extension, Nature Coast Biological Station, and Florida Museum of Natural History; Florida Department of Environmental Protection’s Indian River Lagoon and Tomoka Marsh Aquatic Preserves; North Florida Land Trust; Florida Audubon; Flagler College; Brevard Zoo; and FWC’s Fisheries Independent Monitoring, Habitat and Species Conservation Section, and Florida Keys Wildlife Environmental Area; as well as many dedicated volunteers, students and citizen scientists.

Ornate diamondback terrapin (M.t. macrospilota)

Please send diamondback terrapin sightings to Traci.Castellon@MyFWC.com.

Florida Coastal Mapping Program

By Rene Baumstark

The Florida Coastal Mapping Program (FCMaP) was initiated in 2017 as a coordinating body of Florida State and Federal partners who have a goal of achieving consistent, state-wide, high resolution seafloor data for Florida’s coastal zone in the next decade. These data will provide critical baseline information to support a range of applications including coastal security, resource management, fisheries, storm surge modeling, boating safety, and tourism, as well as future uses, such as renewable energy and offshore aquaculture.

An inventory of existing high-resolution seafloor mapping data collected on Florida’s shelf was undertaken by a technical team comprised of FCMaP partners. The footprints and metadata for 345 datasets were compiled and assessed on whether they met certain criteria such as age, spatial coverage, and resolution.  For the inventory, gap analysis, and prioritization process, the Florida peninsula was separated into six regions based on geomorphological characteristics: Panhandle, Big Bend, West Peninsula, Keys, Southeast, and Northeast. In consideration of differing sensor and survey design requirements, results in each region were further divided into two depth ranges: nearshore (shoreline out to 20 meters) and shelf (20 meters to the continental shelf break).

The gap analysis revealed that less than 20% of Florida’s coastal waters have been mapped using modern bathymetric methods (multibeam sonar or aerial lidar). The overall lack of high-resolution seafloor mapping for Florida is surprising given that Florida’s coastal areas generate more than $30 billion dollars a year in revenue, which is the 2nd highest in the nation. The region with the least amount of high resolution data is the Big Bend nearshore where less than 3% has been mapped with modern technologies. Where any data do exist, they are often lead-line measurements from the late 1800s, with one data point per 100 m2.  The data disparity between regions is large and by comparison, the best-mapped region, Southeast, FL, has modern bathymetry for 86% of its area. The reason for the discrepancy is two-fold; Southeast FL is very densely populated, and the shelf is extremely narrow in comparison with the Big Bend.

High resolution mapping gap assessment results for inshore and deeper waters for six subregions around Florida. The best mapped area are shallow waters of the SE Florida region where 39% of the seafloor has been mapped.

FCMaP is presently soliciting input from managers, planners, and decision-makers to prioritize coastal and seafloor mapping needs. A mapping prioritization tool developed by NOAA (Kendall et al., 2018; Battistia, et al., 2017) was adapted to be a FL-specific application and is being rolled out region by region via a series of stakeholder workshops. Representatives from multiple federal, state, academic, and private entities are introduced to FCMaP and discuss the relevance of high resolution seafloor maps to their regions science and management needs. A single representative from each agency is then tasked with populating the tool with input from their colleagues Analytics are then run on to generate a cumulative prioritization for the region that can be displayed as a map product, and the associated justifications for the mapping need statistically evaluated.

To demonstrate the value of a coordinated approach, FCMaP partners have also engaged in a demonstration seafloor mapping effort in the Big Bend Region. High resolution bathymetry will be collected for select key management areas. These data will be some of the first modern bathymetry collected in this region and the map products will contribute to management efforts such as fisheries stock assessments, seagrass distribution, and oyster reef occurrences. In addition, outcomes from the demonstration will be used used to investigate the influence of the variable geologic framework on coastal response and evolution, providing both enhanced management capacity and science for improved understanding of coastal behavior in this little-understood region of the eastern Gulf of Mexico.

 

References

Battista, T., Buja, K., Christensen, J., Hennessey, J., and Lassiter, K. 2017. Prioritizing Seafloor Mapping for Washington’s Pacific Coast: Sensors, 17(4). https://doi.org/10.3390/s17040701

Kendall, M.S., K. Buja, and C. Menza. 2018. Priorities for Lakebed Mapping in the Proposed Wisconsin-Lake Michigan National Marine Sanctuary. NOAA Technical Memorandum NOS NCCOS 246. Silver Spring, MD. 24 pp.

Light Pollution and Sea Turtle Hatchling Orientation

By Shigetomo Hirama

Sea turtles are long-lived animals that utilize multiple developmental habitats. In all of the habitats, sea turtles encounter with various threats. Although some are naturally occurring (at least they seem to be), the majority of threats are caused by human. These anthropogenic threats in-water habitats include: fisheries’ activities, oil spills, debris ingestions, debris entanglements, boat strikes, dredging, and direct harvesting. On the beach, beach driving, artificial lighting (light pollution), armoring (sea walls, rock revetments, and other infrastructures), oil spills, and egg poaching are threats to nesting and hatchling turtles. Among these threats on the beaches, the installment of armoring structure – sea walls, rock revetments, and other infrastructures – are probably the most important threats, considering sea level rise as a consequence of climate change. Armoring structures are known to increase speed of erosion and may cause permanent loss of beach sand. Although it may not be as important, artificial lighting also is significant threats to the turtles. The artificial lighting differs from the armoring in terms of solving the issues. Coastal armoring, such as a sea wall, is difficult to remove once it is placed; however, we can change light bulb or retrofit light fixtures relatively easily. Through the present project, we provide valuable information to stakeholders to reduce hatchling mortality and increase chance of hatchlings’ survivorship.

Playalinda Beach. An example of a beach with no light pollution.

Artificial lighting alters natural illuminant environment and impacts behavior of wildlife. Nocturnal animals such as bats, moths, and some species of birds, are more susceptible to light pollution than others. Sea turtle hatchlings crawl toward ocean using the visual cues immediately after emerging from sand. The hatchlings disorient on the beach if the intensity of artificial light is relatively high and may never enter the ocean.

Cocoa Beach. An example of a beach with moderate to severe light pollution.

We have been quantifying accuracy of hatchling orientation in over the 20 Florida beaches in past five years. Hatching orientation is one of the subjects of sea turtle biology that has been studied well. Surprisingly, no known work has provided the benchmark orientation data that were collected at a natural beach and compared with the information that were collected at the beaches with varying levels of light pollution. The results of present project showed the accuracy of hatchling orientation varied widely depending on the beaches. The quantitative data of the project are currently in process of publishing in a peer-reviewed journal. In the present article, I provide photographic images that were taken by same camera, setting, and lens at the beaches with no (Playalinda), moderate to severe (Cocoa Beach), and severe (Miami Beach) light pollutions. We hope the data we provide would guide to take practical actions to reduce light pollution.

Miami Beach. An example of a beach with severe light pollution.

Vessel Use Patterns in the Florida Keys National Marine Sanctuary

By Casey Butler, Maria Cooksey, Gabrielle Renchen and Emily Hutchinson

The Keys Fisheries Research program took to the skies in partnership with the Florida Keys National Marine Sanctuary (hereafter Sanctuary) management team to conduct an aerial survey of vessel use in the Sanctuary. Within the boundaries of the Sanctuary lie nationally significant marine resources, including hundreds of uninhabited Keys, the world’s third largest barrier reef, hard-bottom habitat, seagrass beds, mangrove trees, and more than 6,000 species of marine life. The Florida Keys are home for ~79,000 year-round residents and provide a destination for ~5 million visitors annually. Over the last few decades the number of registered vessels has increased, but the activities of these boaters and how their use of Sanctuary resources have changed over time is not well known. Understanding the patterns of boating activity in the Sanctuary is vital to evaluating the sustainable use of the valuable marine resources of the Sanctuary.

Whale Harbor Sandbar is the most popular sandbar in the Keys (331 boats were observed on the Sunday of Memorial Day Weekend 2016).

FWRI scientists flew in small planes over the breathtaking waters of the Keys and recorded the type, location, and activity of every boat, personal water craft, kayak, paddleboard, etc. Over the course of 29 flights in 2016, we counted 52,107 boats. The number of boats peaked at nearly 5,000 during the opening days of lobster season and summer holidays. On average, 19% of boats were involved in fishing, 19% were involved in diving, 13% were anchored (with no visible activity), and 9% of boats were at sandbars. Many of the boats we observed (29%) were in transit at the time; however, these boats likely participated in other activities throughout the day. In addition to diving and fishing, other watersports (e.g., kayaking, paddle boarding, jet skiing) and partying at sandbars were popular among the Sanctuary’s visitors and reflect alternative ways in which people enjoy Florida Keys waters. Our research team conducted a similar aerial survey in 1992, and the comparison of vessel use data between 1992 and 2016 shows that there has been a major increase (~400%) in the popularity of watersports (e.g., kayaking, paddle boarding, jet skiing) and partying at sandbars.

The 1992 aerial survey took place prior to the establishment of the Sanctuary Preservation Areas (Figure 1, SPAs). Establishment of the SPAs in 1997 limited consumptive activities within these areas and was intended to reduce conflicts between fishermen and divers. Because these areas were open to fishing during the 1992 aerial survey – including hook-and-line, recreational lobstering and commercial fishing, this allows us to examine how SPA implementation affected stakeholder activity. Currently, we are evaluating changes in dive and fishing boat spatial distributions after the SPAs were established.

Sombrero Reef, a Sanctuary Preservation Area (SPA) off of Marathon hosts many divers and snorkelers throughout the year.

Besides providing an outstanding office view for our scientists, this project provided essential information to the Florida Keys National Marine Sanctuary managers regarding vessel use in the Sanctuary and how that use has changed over time, which should aid in future management decisions regarding Sanctuary resources.

Watch our video for a glimpse of the scenery from the Florida Keys National Marine Sanctuary aerial survey project:  https://www.youtube.com/watch?v=TxQH3zRdYzk

Gopher Frog Monitoring Project

By Aubrey Greene

The gopher frog is currently being considered for federal protection under the Endangered Species Act. While the gopher frog has experienced serious declines throughout the rest of its range, Florida currently represents a stronghold for the species. Consequently, the gopher frog was delisted as a state-designated Species of Special Concern in January 2017. As a part of the delisting process, a state species action plan was developed for the gopher frog. This action plan calls for the development of a statewide monitoring program for the species. Before the species was delisted, we began a pilot study to increase our understanding of species detection and wetland occupancy rates, as well as to determine the best methodology for a long-term gopher frog monitoring program.

Surveys for the gopher frog monitoring project started in Fall 2015. This project uses seasonal dipnet surveys and frogloggers (automated frog call recorders) to track the status of gopher frogs in 100 wetlands over time. Additional wetlands are also surveyed as time allows to locate new breeding wetlands and track the status of the species in additional known breeding ponds. During FY 2017-18, we surveyed 114 ponds in 22 counties on 29 public or conservation lands for gopher frogs, finding tadpoles in 72 ponds in 21 counties on 24 public lands. These surveys discovered one previously unknown gopher frog breeding pond and observed breeding for the first time in decades in some previously known ponds. Many of the “rediscovered” observations were made in the months following Hurricane Irma, which filled most of the study ponds.

An image of a sonogram of a gopher frog call.

As the data collection phase of this project comes to a close at the end of 2018, in-depth data analyses will begin. Froglogger recordings are already being analyzed using software that recognizes the specific call signature of the species. Unfortunately, this is a very long process due to the large amount of data collected over the three-year project. Dipnet and froglogger data will be analyzed to determine the annual and seasonal patterns of wetland occupancy in each region of the state, as well as the effects of different variables on species detection and wetland occupancy. We will also examine data from both methods to make recommendations about the most efficient sampling methods.