All posts by Jessica Pernell

Bob Glazer’s Climate Work Recognized

by Heather Young

Bob Glazer
Bob Glazer

Associate Research Scientist Bob Glazer has been recognized by the Joint Implementation Working Group of the National Fish, Wildlife, and Plants Climate Adaptation Strategy. He received an Honorable Mention for the Inaugural Climate Adaptation Leadership Award for Natural Resources. The Climate Adaptation Leadership Award honors excellence by outstanding organizations and individuals to reduce climate-related threats and advance the resilience of fish, wildlife and plants in a changing climate. Bob has been key in advancing climate change adaptation initiatives within FWC, participating in the climate adaptation objective team, undertaking and participating in scenario planning efforts throughout Florida. Bob’s work with the State of Florida and as Executive Director of the non-profit Gulf and Caribbean Fisheries Institute has been instrumental in reducing non-climate stressors on marine and coastal systems and developing capacity to address climate change within the management community of marine protected areas. His activities as Chair of the Monroe County Climate Change Advisory Committee have provided adaptation options for the Florida Keys including the adoption of a Climate Action Plan.

Using the Concept of Leaf Area Index in Monitoring Vegetation

by Kent Williges

researchers in bushes
Upland Habitat biologists, Bailey Piper and Tom Carney, set up a fisheye camera to photograph the canopy strata of scrub habitat on Guana River Wildlife Management Area near St. Augustine.

During the last several months, Upland Habitat biologists have been busy testing the applicability of Leaf Area Index (LAI) theory for use in vegetation monitoring in Florida. LAI is defined as the total one‐sided area of leaf tissue per unit ground surface area. It indirectly measures biomass as a function of light availability, and it can be thought of as a method of inventorying the population of leaves in a plant community that absorb sunlight. It is typically used to characterize the plant canopy, and lends itself very well to tracking changes in the canopy biomass.  All land management activities whether they include forest stand thinning, roller chopping, applying herbicide, or application of prescribed fire essentially reduce plant biomass which results in greater light penetration through the canopy strata of a given plant community.  The light availability concept has potential to be incorporated into a standardized rapid assessment vegetation/burn monitoring protocol for evaluating habitat quality that significantly improves efficiency and repeatability by nontechnical personnel.  We are currently testing several instruments that are designed to indirectly assess the LAI of plant canopies in real time by gap fraction analysis.  The basic tenet of gap fraction analysis is that canopy leaf area can be inferred from measurements of canopy gap area (the area not covered by leaves). Gap area can be inferred from canopy photographs taken with a camera equipped with a specialized fisheye lens, or by estimation of the amount of the direct solar beam that penetrates the canopy as measured by various photometers.  Currently, monitoring methods tend to be project specific, and often vary by land management entity. This makes it difficult to compare plant community or fire data collected from different regions of the state, and to compare data collected by various public agencies or the private sector.  In addition, monitoring methods are often complex and intensive, and therefore hard to use by nontechnical personnel. These types of programs essentially rely on measuring plant community structural attributes (basal area, cover, stem density, stem height, etc.) to indirectly estimate vegetation biomass, and usually require a high level of expertise by the data collectors. Our idea is to use light penetration as a substitute for many of the structural attributes used to evaluate habitat quality in Florida plant communities, if it is found they are highly correlated. A rapid assessment method that requires fewer measurements would be more efficient, cost effective, and would be easily repeatable by multiple nontechnical personnel especially on private lands.

man in bushes
Tim Carney recording direct solar penetration with a Li-Cor LAI-2200 photometer in scrub habitat at Guana River WMA.

Recovery Act: Hardbottom mapping and community characterization of the west central Florida Gulf coast

by Ryan Maloney and Sean Keenan

Habitat classification and mapping are a crucial part of fisheries conservation and ecosystem-based management.  Essential fish habitats act as nurseries, feeding, and breeding grounds for many commercially and recreationally important species. Technological advances like side scan sonar and satellite imagery allow researchers to gain a better understanding of where these habitats are located, their aerial extent, and what the habitat and fish community looks like.

The distribution and composition of benthic habitats on the west Florida shelf including submerged aquatic vegetation (SAV) and submerged marine carbonate reef outcroppings (hard bottom) are poorly understood. While these habitats serve as nursery and forage areas for many economically-important reef-fish species (e.g. gag, red snapper, gray snapper and hogfish), benthic mapping and characterization of the benthic communities are nonexistent for a majority of the West Florida continental shelf.

Mapping habitat in such a large area is a daunting task, which requires an extensive amount of time, and can be very costly.  Current methods for characterizing marine habitats include acoustic (side scan sonar) and optical (satellite) imagery.  Side scan sonar provides high resolution (~0.1 m) imagery through processing of acoustic backscatter or echo strength (Figure1). While commercial grade side scan systems have become more cost effective, time and resource requirements for data collection and post-processing still add up. Satellite imagery, in comparison, has a substantially lower cost per unit area and is much more time efficient. Satellite imagery, however, is restricted by water depth and clarity and is more difficult to acquire and has a limited resolution of ~3 m (Figure2).

imagery comparisons
Figure 1. This slide illustrates some or our more commonly used habitat classifications. By utilizing camera ground truthing images, we can better define the corresponding side scan imagery.
satellite imagery
Figure 2. The image to the left represents raw satellite data, while the image to the right shows the delineated habitat defined based on the parameters mentioned.

For this project, the Fisheries Independent Monitoring (FIM) group is compiling past and present side scan sonar surveys contained within two designated study areas.  The areas are divided into a 790 km² area off of Clearwater, FL and 820 km² area just off of Sarasota, FL.  Within each study area, surveys are being scanned and read for the presence of essential fish habitats.  In conjunction with scanning, a drop camera is deployed at each survey site as a ground truthing technique.  All side scan and ground truth data will be compared to preexisting satellite imagery, processed and classified by grant collaborators.  By comparing and contrasting side scan sonar with satellite imagery, this project is exploring different methods to map essential fish habitats at varying scales (Figure 3).

side scan sonar mosaic
Figure 3. A side scan sonar mosaic, with defined habitat outlined, shows that brighter imagery returns, correspond to hard harder substrates. These returns are inversely related to satellite imagery, where we see dark returns representing hard bottom.

With a more economical way of characterizing nearshore marine habitats, scientists and fisheries managers can 1) establish the exact locations and spatial extent of these habitats; 2) monitor any changes in habitats and fish communities; and 3) implement habitat-based fisheries independent surveys.

Bonefish Research

Dr. Liz Wallace is working closely with partners at the Bonefish and Tarpon Trust, Cape Eleuthera Institute and Fisheries Conservation Foundation to study population connectivity between bonefish in Florida, The Bahamas and across the Caribbean. Since this project began, the communications team has teamed up with Liz to share project updates, photos and videos with anglers and the general public using social media and the FWRI website. Angler outreach and education is an important part of this study, and our online efforts aim to inform anglers and encourage them to get involved by collecting bonefish fin clips for ongoing genetics research. The data collected during this study will ultimately benefit the fishery, and our team will continue working with researchers to fulfill their outreach needs for this project.

The following is a sample of posts created by the Communications Office to promote this project.

FWRI Website
Bonefish at MyFWC.com/Research

On Facebook
February 29, 2016
October 6, 2015
May 29, 2015
May 4, 2015

On Flickr
Bonefish Genetics Research in Andros, Bahamas – February 2016
Bonefish Genetics Research – June 2015
Bonefish Genetics Research in Grand Bahama – April 2015

On Instagram
https://www.instagram.com/p/BCfkto0w9rZ/
https://www.instagram.com/p/BCLtVE2MWcS/
https://www.instagram.com/p/3RIqFFQ9j6/

 

Be sure to join us on all our social media channels.
Facebook | Twitter | Instagram | Flickr | YouTube

Wild Turkey Research 

by Tyler Pittman 

The wild turkey is one of the most wide-ranging upland gamebirds in North America with five sub-species inhabiting all of the contiguous United States as well as regions of southern Canada and northern Mexico. The common eastern sub-species inhabits northern Florida, and the Osceola sub-species, unique to Florida, inhabits the central and southern parts of the state. Wild turkey were almost extirpated from Florida in the early 20th century due to overharvest but after successful restoration efforts wild turkey are now found and harvested in all of Florida’s 67 counties.  Florida has become a destination for hunters from around the world who travel here for an opportunity to harvest an Osceola turkey. Hunters in Florida harvest over 20,000 wild turkey annually, making continued research and monitoring essential to maintaining the population and preventing another extirpation event.

Beginning in 2014, FWC partnered with researchers from Tall Timbers Research Station and Land Conservancy, the University of Tennessee-Knoxville, and the University of Florida to document the breeding chronology of wild turkey across the state of Florida in an effort to establish harvest season dates that benefit both wild turkey populations and wild turkey hunters. We are currently documenting nesting chronology using 68 wild turkey hens, captured and fitted with tracking devices, and we have deployed 36 automated audio recording devices to document the chronology of male breeding activity by recording gobbling. Eventually, the chronology information from female and male breeding activity will allow us to establish season dates after the peak of female nesting activity and during the peak of male breeding activity when fewer females are available to breed with. This will minimize the impact of harvest on females and maximize hunter satisfaction.

The South Florida Deer Research Project  

by Elina Garrison

deer with radio collar
Monitoring deer through wet and dry seasons allows us to better understand how annual and seasonal hydrological changes impact deer movement, habitat use and survival.

Throughout the state, white-tailed deer (Odocoileus virginianus) are one of the most valued and sought-after game species. In South Florida, deer are also the most important prey species of the endangered Florida panther (Puma concolor coryi).  In recent years, particularly in the southern portion of the Big Cypress National Preserve (BCNP) and Everglades National Park, the area has experienced deer declines. Previous deer research in the BCNP region dates back to the early 1990s. Since that time, the area has changed significantly, including hydrological changes, an increase in the panther population, and changes in other predator populations. Therefore, there was a need for up-to-date information on deer survival and causes of mortality to better understand deer ecology in South Florida. In addition, there was a need for a cost-effective monitoring methodology for more reliable deer density estimates to guide long term management.

panther on trail
The team has deployed 180 trail cameras throughout the study area. The cameras are used to develop a new survey technique for deer, but also to capture activity and other important information for a variety of wildlife species, including Florida panthers.

To address these research and management needs, FWC partnered with the University of Georgia and other agencies to begin a large-scale, multi-year study called “The South Florida Deer Research Project.” Since 2015, the team has captured and fitted over 200 deer with GPS collars in the Florida Panther National Wildlife Refuge and Bear Island and North Additional Units of BCNP. We are also using trail cameras, in combination with the marked deer, to develop a monitoring tool. In addition, cameras provide information on fawning period, recruitment, timing of antler casting, and activity patterns of deer relative to season, weather events, and human activity. The study will continue through 2018. For more information and quarterly updates, please visit the South Florida Deer project website:  http://myfwc.com/hunting/by-species/deer/project/

Sex in the Sea and Gonadal Histology 

by Laura Crabtree

Our reproductive dynamics group at FWRI is combining histological assessments of fish gonadal development with emerging issues in reproductive biology to better understand the complex systems involved in fish reproductive success and productivity.

men and women on boat with fish
The fisheries research group taking gonad biopsies from red drum, which were then released, several miles offshore of Tampa Bay.

Sue Lowerre-Barbieri leads our team of biologists with goals aimed at answering questions about the reproductive strategies of key fish species and how they are affected by fishing pressure. An important issue for us and other fisheries biologists has been the standardization of terminology and histological classification schemes so that we can make consistent and accurate comparisons among studies. Our collaboration in the scientific community, including other state and federal biologists along with academic experts at other institutions, have helped us advance this effort.

We currently study spotted seatrout, red drum, and seven reef fish species: red grouper, gag, scamp, red porgy, red snapper, vermilion snapper, and gray triggerfish.  Most of our reef fish gonad samples come from the West Florida Shelf Reef Fish Survey that Fisheries Independent Monitoring (FIM) has been conducting since 2008. They’ve collected over 6,000 samples from 86 species that have allowed us to develop baseline knowledge of where and when these species spawn and to create species-specific reproductive studies to estimate fecundity and reproductive behavior.

Our long term goals include the following:

cells
Figure 1. Oocyte developmental stages on the left side with key histological indicators on the right side.
  • Mapping the spawning sites of target species by assessing where actively spawning females were collected
  • Assessing reproductive timing of these species by evaluating the season and time at which females of different reproductive phases are collected
  • Developing gonadal histology photographic reference guides for key species that include the histological indicators for determining reproductive state (Figure 1)
  • Publishing a fish reproductive histology atlas that can be used as a reference guide for biologists throughout the scientific community

drawing of fishOne of our most recent and exciting projects is a three-year Marine Fisheries Initiative (MARFIN) funded study assessing male abundance and factors affecting reproductive potential of gag, Mycteroperca microlepis, in the eastern Gulf of Mexico.

two girls on boat holding fish
Hayden and Jordie, two of our newest members, holding a gag during a data collecting trip in the Gulf of Mexico in 2016.

Our objectives are to determine their sex ratio; time of sex change; sex-specific differences in spatial ecology; and to evaluate the accuracy of sex determination methods (i.e. external pigmentation). The fish are caught by hook and line up to 180 miles offshore of Panama City. We also use a GoPro camera array to visually assess the relative abundance of fish and characterize habitat.

Overall, our results will provide additional data needed for stock assessments and result in improved management. We are collaborating on this project with FIM, Fish Health, Dr. Chris Koenig, and the National Marine Fisheries Service and will share the data with state and federal scientists.

Many of the species we study are hermaphroditic fish. There is reason to believe hermaphroditic fish are capable of changing sex quickly in response to instability in local populations so understanding this strategy and how fishing impacts it at the individual level as well as the population level are an important parameter in fishery management. Our reproductive dynamics group is developing expertise in understanding the complexities of sexual patterns such as social structures and the vulnerabilities they may have to fishing pressure.