Project Work Plan
Department of Interior USGS GE PES
Fiscal Year 2014 Study Work Plan
Study Title: Habitat use of threatened and endangered sea turtles in the Greater Everglades
Phase I Study Start Date: 1 October, 2009
Phase I Study End Date: 30 September, 2013
Phase II Study Start Date: 1 October, 2013
Phase II Study End Date: 30 September, 2017
Web Sites: www.seaturtle.org
Duration: 5 years from FY2009- 2013 (Phase I), and 5 years from FY2013-2017 (Phase II)
Location (Subregions, Counties, Park or Refuge): Southern Florida Keys including area within the Florida Keys National Marine Sanctuary and Key West National Wildlife Refuge, Great White Heron National Wildlife Refuge, Crocodile Lake National Wildlife Refuge, Dry Tortugas National Park, Everglades National Park, Biscayne National Park.
Funding Source: GE PES
Previous Complementary Funding Sources:
National Park Service to USGS PI Hart in FY2008
GE PES and matching USGS Coastal and Marine Geology (CMG) in FY2009 GE PES and CMG in FY2010
GE PES and CMG in FY2011
GE PES and CMG in FY2012
GE PES in FY2013
Funding History: This project has integrated with the USGS Coral Reef Ecosystem Studies (CREST) project funded by USGS Coastal and Marine Geology (CMG).
FY 14 USGS Funding: GE PES
Principal Investigator: Kristen M. Hart
USGS Project Officer: Kristen M. Hart
USGS Technical Officer: Scott Padgett
Supporting Organizations: US National Park Service
Associated / Linked Studies (Leveraged funding): High-resolution mapping of the Dry Tortugas (USGS PI Zawada, Coastal and Marine Geology Program)
Overview & Objective(s): Institution of marine protected areas (MPAs) in which human use is highly regulated has become a priority management tool for at-risk coral reef habitats. The effectiveness of MPAs may be heavily dependent upon reserve factors such as size, placement or location, and enforcement of protected area boundaries, as well as whether adequate protection for vulnerable life stages of key species is provided in protected habitats. In the Dry Tortugas National Park (DRTO), several MPAs have been established to protect natural and fisheries resources and associated coral reef habitats. The first phase of this project used a coupled habitat + species sampling approach within and around the Research Natural Area (RNA) of DRTO. Specifically, we assessed turtle use of habitat in and around no-take areas of the RNA by several species of federally endangered sea turtles (i.e., green turtles (Chelonia mydas), hawksbills (Eretmochelys imbricata), and loggerheads (Caretta caretta). Green turtles are almost exclusively herbivorous, consuming seagrasses and algae, hawksbills eat sponges, and thus are found associated with coral reefs and sponge cover, and loggerheads feed on benthic invertebrates such as lobsters and crabs, as well as on fishery discards. Thus, these species are directly linked to key habitats of interest in DRTO and the surrounding waters. Green turtles and loggerheads also nest regularly on the sandy upland beaches of the Tortugas islands.
Products from first phase of project:
- Hart et al. (2013) Biological Conservation
- Hart et al. (2013) PLoS ONE
- Shaver et al. (2013) Reptiles in Research
- Shaver et al. (2013) Ecology and Evolution
- Bjorndal et al. (2013) Marine Biology
- Hart et al. (2012) Marine Ecology Progress Series
- Hart et al. (2012) Biological Conservation
- Hart et al. (2012) NPS chapter, 5 yr RNA report
- Hart et al. (2010) Aquatic Biology
- Zawada and Hart USGS Fact Sheet
- Hart et al. (2009) NPS chapter, 3 yr RNA report
- Numerous presentations at scientific meetings (e.g., International Sea Turtle Symposia 2008-2013, Florida Keys Science Meeting 2010)
Several other products (manuscripts) are in prep:
- Hart et al., Loggerhead use of Dry Tortugas National Park during the breeding season
- Hart et al., Dry Tortugas nesting sea turtles: Use of the Florida Keys National Marine Sanctuary
- Hart et al., Dry Tortugas loggerheads: Connection to Bahamian foraging grounds
Specific objectives of the project that continue from Phase I to Phase II (FY2013-FY2017) are as follows:
- Quantitatively determine patterns of turtle habitat use inside and outside the RNA by instrumenting turtles with satellite tags and analyzing acoustic data previously collected on our own acoustic receivers (N=7) and those of our partners (N=72). With acoustically-logged data that has been collected, we are assessing the proportion of time each turtle spends inside the RNA, and with satellite-derived data, we are assessing the proportion of time each turtle spends outside the RNA or in areas not adjacent to acoustic receivers. Such information will be important for Park managers to assess appropriateness of current RNA boundaries for these high-profile endangered species.
- Include a molecular genetic component in our project to develop an understanding of the linkages and connections among endangered sea turtles using DRTO and potentially other protected areas in the U. S. (i.e., Everglades National Park (ENP), Florida Keys National Marine Sanctuary (FKNMS)) and other countries. Such information is necessary for overall sea turtle population restoration and recovery efforts.
- Include a diet component in our project to assess direct use of park resources by sea turtles. Specifically, we are using gastric lavages and isotope sampling to assess diet of all three species of sea turtles.
- Estimate growth rates for juvenile green turtles that are resident within DRTO.
Specific Relevance to Major Unanswered Questions and Information Needs Identified:
|Figure 1. http://www.seaturtle.org/tracking/?project_id=402|
This project addresses the specific resource management information need regarding endangered species use of Park resources, and condition and location of those resources (i.e., seagrass, sponge, and hardbottom habitats, as well as nesting beaches). The significance and priority of the issue to the Park or the NPS is that such habitat in DRTO may serve as critical habitat for this endangered species. Such critical habitats must be considered in Recovery Plans for the species aimed at restoring sea turtle population numbers. In addition, with climate change scenarios, critical nesting beaches must be included in recovery plans and population restoration efforts. The condition of the nesting beaches in DRTO has been affected by invasive Australian pines (Casuarina equisetifolia), and a removal program in the mid 1990s failed to remove roots and stumps from Loggerhead Key. Thus, significant restoration of this important nesting beach remains an issue for both adults and hatchlings of these endangered marine turtle species.
Of the three overarching restoration questions previously laid out in the U.S. Department of the Interior Science Plan in Support of Ecosystem Restoration, Preservation, and Protection in South Florida, this project directly address two of these:
- What actions will restore, protect, and maintain natural resources on DOI lands in South Florida?
- What actions will recover South Florida's threatened and endangered species?
Additionally, since we have the opportunity to tag nesting female sea turtles using DRTO beaches, the U.S. Fish and Wildlife Service (USFWS) and the National Marine Fisheries Service (NMFS) will benefit from the information derived from the proposed tasks; essentially, the former has jurisdiction and responsibility for endangered sea turtles while they are on land, and the latter has jurisdiction and responsibility for them when they are in the water. Thus, this project not only benefits other DOI agency missions of the USGS, NPS, and USFWS, but also that of the Department of Commerce (DOC; NMFS).
Using new technologies, this project is currently using state-of the art underwater acoustic and satellite technology to track movements of endangered sea turtles within and outside of the boundaries of DRTO. Activities proposed here relate to and complement one component of the State of FLFWC fish work to deploy and utilize an acoustic array in the RNA and around DRTO. The goal of the FLFWC effort is to examine the fine-scale movement patterns and core utilization areas of exploited fish species to determine the spatial adequacy of existing reserve boundaries. FLFWC and our project share data from receivers to expand on the utility of our 'own' receivers. Unlike the fish project, this turtle tracking project will contain an "outside the RNA" component by utilizing satellite data acquired from satellite tags deployed alongside acoustic tags on sea turtles; data derived from these satellite tags is already informing managers of turtle habitat use outside the RNA (i.e., in the Bahamas, off Mexico, off Sanibel and Naples, and throughout the Florida Keys):
Such information is revealing whether the boundaries of the RNA should be adjusted in order to more adequately protect endangered turtles using specific benthic habitats for forage and upland habitats for nesting. The integrated Hart-Zawada project will rely on both USGS-GE PES and USGS Coastal and Marine Geology funding to conduct endangered sea turtle tracking in concert with high-resolution mapping and fine-scale benthic habitat characterization using the Along-Track-Reef-Imaging-System (ATRIS).
Summary of Progress:
Accomplishments To Date:
Since 2008 we have deployed N=84 satellite tags and N=95 acoustic tags and have successfully worked out turtle capture methods both on land and in the water. We are recapturing nesting female green and loggerhead turtles, as they often return to nest on their natal beaches every other year. Thus, we are beginning to shed light on the number of nesting females in the genetically-distinct DRTO loggerhead population using analysis of this unique long-term mark-recapture dataset.
We have published several key manuscripts:
Hart KM, Zawada DG, Fujisaki I, Lidz BH (2010) Inter-nesting habitat-use patterns of loggerhead sea turtles: Enhancing satellite tracking with benthic mapping. Aquatic Biology.11:77-90.
Hart KM (2010) Use of protected areas by threatened and endangered marine turtles in the Dry Tortugas Pg:12-13, In: Hallac, D and J. Hunt, editors. Implementing the Dry Tortugas National Park Research Natural Areas Science Plan: the 3-year report. South Florida Natural Resources Center, Everglades and Dry Tortugas National Parks, Homestead, FL, and the Florida Fish and Wildlife Conservation Commission, Tallahassee, FL. 37 pp.
Hart KM, Lamont MM, Fujisaki I, Tucker AD, Carthy RR (2012) Common coastal foraging areas for loggerheads in the Gulf of Mexico: opportunities for marine conservation. Biological Conservation 145:185-194.
Hart KM, Sartain AR, Fujisaki I, Pratt HL Jr, Morley D, Feeley MW (2012) Home range, habitat use and migrations of hawksbill turtles tracked from Dry Tortugas National Park, Florida, USA. Marine Ecology Progress Series 457:193-207, doi: http://dx.doi.org/10.3354/meps09744.
Hart KM, Fujisaki I, Sartain AR (2012) Chapter 5: Use of Dry Tortugas National Park by threatened and endangered marine turtles. Pp 28-33. In: Ziegler, T.A. and Hunt, J., editors. 2012. Implementing the Dry Tortugas National Park Research Natural Area Science Plan: The 5-Year Report 2012. South Florida Natural Resources Center, Everglades and Dry Tortugas National Parks, Homestead, FL, and the Florida Fish and Wildlife Conservation Commission, Tallahassee, FL. 63 pp.
Bjorndal KA, Schroeder BA, Foley AM, Witherington BE, Bressette M, Clark D, Herren RM, Arendt MD, Schmid JR, Meylan AB, Meylan PA, Provancha JA, Hart KM, Lamont MM, Carthy RR, Bolten AB (2013) Temporal and spatial variation in growth rates of loggerhead sea turtles (Caretta caretta) in the Northwest Atlantic, Marine Biology 160:2711-2721, doi http://dx.doi.org/10.1007/s00227-013-2264-y.
Hart KM, Zawada DG, Fujisaki I, Lidz BH (2013) Habitat use of breeding green turtles Chelonia mydas tagged in Dry Tortugas National Park: Making use of local and regional MPAs. Biological Conservation 161:142-154, http://dx.doi.org/10.1016/j.biocon.2013.03.019.
During FY14, we will continue to conduct both nesting beach work and in-water turtle captures in DRTO to increase the sample sizes of tagged/sampled individuals for all three species (hawksbills, green turtles, and loggerheads). We will specifically plan capture and tagging efforts to assess the extent of loggerhead and green turtle inter-nesting habitat (50% core use area), as well as where additional hawksbills may be found. We will continue catching juvenile green turtles in the shallow flat around Bird/Long Key and refine growth rate estimates for these young turtles. Additionally, we will process all lavage samples, conduct isotope analysis, and conduct genetic analysis to determine stock structure for each species. We will continue to update information on residence times for turtles residing in and using DRTO. The combined data sets will provide insight into (1) the effectiveness of the DRTO RNA for protecting threatened and endangered marine turtles and their requisite habitats, (2) the condition of those habitats (i.e., seagrass beds), and (3) the development of more effective decision-support tools to adaptively manage coral ecosystems.
In addition, with our renewed National Marine Fisheries Service endangered species permit to catch turtles in the water, we expanded our study site boundaries and will be able to add in-water sea turtle work in the Everglades. In FY15, we are also hoping to expand our turtle capture efforts in the water to Biscayne Bay (so into Biscayne National Park).
Planned Products for FY14: Products that will result from this project include at least 3 major publications (two to share tracking data and one to present genetic analysis results, likely in Endangered Species Research, Marine Ecology Progress Series, and Conservation Genetics), as well as presentations at regional, national and international scientific conferences (i.e., Annual Sea Turtle Symposium). Also, annual and project end reports will be filed in compliance with USGS and NPS, State of Florida, and NMFS permit requirements. The public will be informed through www.seaturtle.org/tracking and USGS Highlights. Funding agencies and other interested parties may log in to the website daily to observe turtle locations and habitat use trends. As well, we will generate GIS layers of benthic habitat maps each year after Tortugas cruises. Maps will be made available to the USGS and NPS after processing, generally several months after a cruise. Hart will ensure transfer of key results on sea turtle habitat use patterns and genetic composition to NMFS for inclusion in Recovery Plans for all three species of sea turtles.
Title of Task 1: Habitat use of threatened and endangered sea turtles in the Greater Everglades
Task Funding: GE PES
Task Leaders: Kristen M. Hart
Task priority: High
Task Personnel: Mike Cherkiss
Task Summary and Objectives: The purpose of this task is to capture and tag sea turtles in the Dry Tortugas National Park with standard PIT and flipper tags, as well as state-of-the-art satellite tags. Capture sites will be on nesting beaches (i.e., Loggerhead Key, East Key) and in the water near Bush Key and Long Key as well as near Pulaski Light; capture sites will be both inside and outside the RNA. We will work-up each individual sea turtle to obtain diet and genetic samples, as well as morphometric information. Tracking efforts will involve daily uploads of locations derived from satellite tags affixed to a proportion of each turtles for each species.
Work to be undertaken during the project and a description of the methods and procedures:
- Conduct fieldwork to capture and tag sea turtles from both nesting beaches and in-water feeding grounds. Outfit a subset of turtles with a satellite tag. Each turtle will be sampled for diet and genetics. We will apply internal PIT and external Inconel tags to all turtles captured, and take standard morphometric measurements and weight (when possible). Data will be used to determine (1) size class and condition [including fibropapillomatosis (FP) disease presence]) of green sea turtles using the RNA (because of the remoteness of DRTO, we hypothesize that FP will not be commonly seen on green turtles sampled in the RNA); (2) diet of green sea turtles using the RNA; (3) potential links to other sea turtle populations if some turtles that we capture are already tagged from other studies.
- Examine movement patterns of tagged turtles to determine residence times and habitat use relationships. In particular, we will quantify fine-scale movement patterns and core utilization areas of endangered sea turtles to determine the spatial habitat use patterns both inside and outside the RNA by using satellite and acoustic tracking technologies. We will characterize the habitat features that are utilized by these turtles by relating tracks derived from acoustic and satellite telemetry data to both static (i.e., bathymetry)) and dynamic (i.e., temperature, salinity, food resource location) features of the RNA. We will analyze location data to examine whether locations received were indicative of directed or nondirected (sedentary) movements and behaviors (i.e., by analyzing perceived swim speed, direction of travel, etc.). We will use the Satellite Tracking and Analysis tool (STAT) (Coyne and Godley 2005) available on www.seaturtle.org/tracking to manage satellite telemetry data and maximize the potential of these relatively expensive data. An extremely valuable aspect of STAT is its ability to automatically retrieve, parse, and store telemetry data from the Argos Satellite network. A suite of summary maps, tables, and graphs are updated each day, allowing investigators to easily check each of the tagged animals. STAT also provides an array of mapping, filtering, and export functions to facilitate data analysis, as well as access to bathymetry, sea surface temperature, chlorophyll, sea surface height, and ocean surface currents, thus allowing researchers to see turtle movement in the context of the local environment (Polovina et al. 2000; 2004). The centers of turtle activity will be analyzed using the Animal Movement ™ extension for ARCVIEW 3.2 to give home ranges using kernel-based frequency distributions of locations. Home ranges will be compared to spatially explicit environmental data (e.g., distribution of continuous and discontinuous seagrass) based on available and created (through NOAA) GIS layers. We will also employ switching state-space modeling (SSM) to infer foraging areas and migration corridors for all satellite-tracked individuals.
- Analyze location information to determine the spatial adequacy of existing reserve boundaries for these threatened and endangered marine turtle species. We will also compare satellite and acoustic data from the same turtle to determine consistency of location data derived from both remote tracking methods
- Identify genetic diversity of sea turtles in the Dry Tortugas and compare it to other previously sampled sea turtles from other areas in south Florida and beyond. Each sea turtle will be sampled for genetics during the work-up procedure. Samples will be sent for analysis to one of several labs. By using previously developed molecular markers and analyzing mitochondrial DNA from each turtle to obtain genotypes, we can assess the likelihood that these turtles are all from the same or several different nesting beaches. This analysis will reveal genetic linkages to other sea turtle populations sampled elsewhere. We will analyze mitochondrial DNA control region sequences and nuclear microsatellite genotypes and compare data from DRTO turtles to sequences posted on GENBANK. The program ARLEQUIN version 3.01 (Excoffier et al. 2005) will be used to characterize genetic diversity, and to assess genetic structure through exact tests of population differentiation (Raymond and Rousset 1995). Bayesian clustering analyses implemented by STRUCTURE version 2.1 will be used to estimate connectivity revealed by microsatellite markers without assuming prior population definitions (Pritchard et al. 2000). In addition, the Mixed Stock Analysis (Pella and Milner 2001) method will be used to trace natal origins of these sea turtles.
- Identify additional funding sources, apply for grants to supplement PES funding.
Specific Task Products:
Product with delivery date
Hart, K.M., Zawada, D.G., Sartain, A.R., Fujisaki, I. Submitted January 2014, currently in review. Choice of nesting beach governs extent of submerged habitat use for breeding loggerheads in Dry Tortugas National Park, Oryx.
Seven presentations (2 posters, 5 talks) at the 34th International Sea Turtle Symposium (April 14-18, 2014, New Orleans, Louisiana).
We will present results of sea turtle tracking and capture efforts at the Southeast Regional Sea Turtle meetings (Fall 2014).
USGS-Hart will work with collaborators Naro-Maciel and B. Shamblin to synthesize results of ongoing genetic analysis for reports, presentations, and publications. We expect that one at least one peer-reviewed manuscript will result from the genetic analysis (submission planned for August 2014).
Coyne MS, Godley BJ (2005) Satellite Tracking and Analysis Tool (STAT): an integrated system for archiving, analyzing and mapping animal tracking data. Marine Ecology Progress Series 301:1-7.
Excoffier L, Laval G, Schneider S (2005). Arlequin version 3.0: An integrated software package for population genetics data analysis. Evolutionary Bioinformatics Online 1:47-50.
Fonseca MS, Uhrin AV, Currin CA, Burke JS, Field DW, Addison CA, Wood LL, Piniak GA, Viehman TS, Bonn CS (2006). Ongoing Monitoring of Tortugas Ecological Reserve: Assessing the Consequences of Reserve Designation. NOAA Technical Memorandum NOS NCCOS 22.
Franklin EC, Ault JS, Smith SG, Luo J, Meester GA, Diaz GA, Chiappone M, Swanson DW, Miller SL, Bohnsack JA (2003) Benthic habitat mapping in the Tortugas region, Florida. Marine Geodesy 26:19-34.
Pella J, Masuda M (2001) Bayesian methods for analysis of stock mixtures from genetic characters. Fishery Bulletin 9:151-167.
Polovina JJ, Kobayashi DR, Parker DM, Seki MP, Balazs GH (2000) Turtles on the edge: movement of loggerhead turtles (Caretta caretta) along oceanic fronts, spanning longline fishing grounds in the central North Pacific, 1997-1998. Fisheries Oceanography 9(1): 71-82.
Polovina JJ, Balazs GH, Howell EA, Parker DM, Seki MP, Dutton PH (2004). Forage and migration habitat of loggerhead (Caretta caretta) and olive ridley (Lepidochelys olivacea) sea turtles in the central North Pacific Ocean. Fisheries Oceanography 13 (1): 36-51.
Pritchard JK, Stephens M, Donnelly P (2000) Inference of population structure using multilocus genotype data. Genetics 155:945-959.
Raymond M, Rousset F (1995). An exact test for population differentiation. Evolution 49:1280-1283.