Marine Turtle Newsletter - Seaturtle.org

Marine Turtle Newsletter Issue Number 145

April 2015

Leatherback skull from Suriname in the late 1960s with signs of injury from a jaguar. Photo credit: N. Mrosovsky. Editorial Cause and Call for Modification of the Bi-National Recovery Plan for the Kemp’s Ridley Sea Turtle (Lepidochelys kempii) - Second Revision............................................CW Caillouet, Jr. et al. Articles Radio Frequency Identification Technology and Marine Turtles: Investigation of Passive Integrated Transponder (PIT) Tags and Readers...............................................SP Epperly et al. Contrasting Incubation Data for Lepidochelys olivacea Highlight the Need for More Experimentation and Detailed Reporting.................................................AM Mérida et al. Unmanned Aerial Vehicles (UAVs) for Monitoring Sea Turtles in Near-Shore Waters...............................E Bevan et al. Settling Down in Hawaii: Adaptation of Captive-bred Green Turtles Released from the Maui Ocean Center....G Balazs et al. Announcements Recent Publications

Marine Turtle Newsletter No. 145, 2015 - Page 1

ISSN 0839-7708

Editors:

Managing Editor:

Kelly R. Stewart The Ocean Foundation c/o Marine Mammal and Turtle Division Southwest Fisheries Science Center, NOAA-NMFS 8901 La Jolla Shores Dr. La Jolla, California 92037 USA E-mail: [email protected] Fax: +1 858-546-7003

Matthew H. Godfrey NC Sea Turtle Project NC Wildlife Resources Commission 1507 Ann St. Beaufort, NC 28516 USA E-mail: [email protected]

Michael S. Coyne SEATURTLE.ORG 1 Southampton Place Durham, NC 27705, USA E-mail: [email protected] Fax: +1 919 684-8741

Founding Editor:

Editorial Assistant:

On-line Assistant:

Nicholas Mrosovsky University of Toronto, Canada

Natalie C. Williams University of Florida, USA

ALan F. Rees University of Exeter in Cornwall, UK

Editorial Board: Brendan J. Godley & Annette C. Broderick (Editors Emeriti) University of Exeter in Cornwall, UK

Nicolas J. Pilcher Marine Research Foundation, Malaysia

George H. Balazs National Marine Fisheries Service, Hawaii, USA

Manjula Tiwari National Marine Fisheries Service, La Jolla, USA

Alan B. Bolten University of Florida, USA

ALan F. Rees University of Exeter in Cornwall, UK

Robert P. van Dam Chelonia, Inc. Puerto Rico, USA

Kartik Shanker Indian Institute of Science, Bangalore, India

Angela Formia University of Florence, Italy

Oğuz Türkozan Adnan Menderes University, Turkey

Colin Limpus Queensland Turtle Research Project, Australia

Jeanette Wyneken Florida Atlantic University, USA

MTN Online - The Marine Turtle Newsletter is available at the MTN web site: http://www.seaturtle.org/mtn/. Subscriptions and Donations - Subscriptions and donations towards the production of the MTN should be made online at http://www.seaturtle.org/ mtn/ or c/o SEATURTLE.ORG (see inside back cover for details).

This issue was produced with assistance from:

Contact [email protected] to become a sponsor of the Marine Turtle Newsletter or visit http://www.seaturtle.org/mtn/donate.shtml

The MTN-Online is produced and managed by ALan Rees and Michael Coyne. Marine Turtle Newsletter No. 145, 2015 - Page 1

© Marine Turtle Newsletter

Cause and Call for Modification of the Bi-National Recovery Plan for the Kemp’s Ridley Sea Turtle (Lepidochelys kempii) - Second Revision Charles W. Caillouet, Jr.1, Benny J. Gallaway2 & André M. Landry, Jr.3

119 Victoria Drive West, Montgomery, TX 77356-8446 USA (E-mail: [email protected]); 2LGL Ecological Research Associates, Inc., Bryan, TX 70802 USA (E-mail: [email protected]); 3Departments of Marine Biology, Wildlife and Fisheries Sciences, and Marine Sciences, Texas A&M University at Galveston, Galveston, TX 77553 USA (E-mail: [email protected]) 1

We propose that the Bi-national Recovery Plan for the Kemp’s Ridley Sea Turtle (Lepidochelys kempii) - Second Revision (NMFS et al. 2011) be revisited and modified in 2015. NMFS (2010) and NMFS et al. (2011) state that approved recovery plans are subject to modification as dictated by new findings, changes in species status, and completion of recovery actions. Although Kemp’s ridley recovery actions have not been completed, many new findings and observed changes in its species status after 2009 warrant modification of the recovery plan. Kemp’s ridley’s “species status” was described in the Executive Summary of NMFS et al. (2011) as “Current Status: The Kemp’s ridley nesting population is exponentially increasing, which may indicate a similar increase in the population as a whole.” However, its exponential growth was unexpectedly interrupted in 2010 (Caillouet 2010, 2011, 2014; Crowder & Heppell 2011; Gallaway et al. 2013; Gallaway & Caillouet 2014; Gallaway & Gazey 2014; Heppell 2014, In press). The ESA of 1973 (as amended) requires review of all listed species at least once every 5 years. According to NMFS (2010), an approved recovery plan should be reviewed immediately following a 5-yr review, to determine whether it needs to be brought up to date. The required 5-yr review for Kemp’s ridley is almost three years overdue (see NMFS & USFWS 2007). Approved recovery plans can be modified by an update, revision, or addendum, the choice among which depends upon various criteria, including background information, recovery strategy, recovery objectives and criteria, and recovery actions and implementation schedule (NMFS 2010). Many new findings (e.g., Seney & Landry 2008; Caillouet 2010, 2011; Putman et al. 2010; Bjorndal et al. 2011; Campagna et al. 2011; Crowder & Heppell 2011; Finkbeiner et al. 2011; Smith et al. 2011) were published before the recovery plan (NMFS et al. 2011) was implemented, and more have been published since (e.g., Antonio et al. 2011; Caillouet 2012a, b; Garrison & Sasso 2012; Coleman 2013; Putman et al. 2012, 2013; Gallaway et al. 2013; Lewison et al. 2013; Belter 2014; Bevan et al. 2014; Bjorndal et al. 2014; Gallaway & Caillouet 2014; Gallaway & Gazey 2014; Heppell 2014, In press; Valverde 2014). In our opinion, the most significant new findings were (1) interruption of the Kemp’s ridley population’s pre-2010 exponential growth within the Gulf of Mexico in 2010 (Burchfield & Peña 2010; Caillouet 2011; Crowder & Heppell 2011; Gallaway et al. 2013; www.nps.gov/pais/naturescience/ kridley.htm), and (2) the population’s decline in 2013 and 2014 (Caillouet 2014; Gallaway & Caillouet 2014; Gallaway & Gazey 2014; Heppell 2014, In press). The conventional index of Kemp’s ridley population size is the annual number of nests (i.e., clutches laid) on three beach segments combined (Rancho Nuevo, Barra del Tordo-Playa Dos, and Tepehuajes) in Tamaulipas, Mexico (Caillouet 2014). Post-2010 changes in this index were extraordinary (Caillouet 2014), compared to the recovery plan’s optimistic prediction of 19% per year growth of the population during years 2010-2020, under

an assumption that survival rates in 2009 remained constant within each life stage (NMFS et al. 2011). Investigations aimed at determining the cause or causes of post2009 changes in the Kemp’s ridley population have been underway since the Deepwater Horizon (DWH) oil spill began on 20 April 2010 (Bjorndal et al. 2011; Gallaway et al. 2013; Fikes et al. 2014; www.gulfspillrestoration.noaa.gov; www.publicnewsservice. org/2015-01-20/endangered-species-and-wildlife/penalty-phasebegins-in-bp-oil-spill-disaster-trial/a44038-1). NOAA’s Natural Resource Damage Assessment (NRDA, www.gulfspillrestoration. noaa.gov) should provide additional new findings. Among other possible causes, mortality associated with incidental capture of Kemp’s ridleys in shrimp trawls was examined and estimated, but accounted for 21.6% or less of estimated total mortality in 2010 (Gallaway et al. 2013; Gallaway & Caillouet 2014; Gallaway & Gazey 2014). The NMFS Southeast Regional Office conducted ESA Section 7 consultations in 2012 and 2014, regarding sea turtle regulations associated with Southeast U.S. shrimp fisheries in Federal waters (http://sero.nmfs.noaa.gov/protected_resources/ sea_turtles/documents/shrimp_biological_opinion_2014.pdf). Biological Opinions issued in May 2012 and April 2014 concluded that continued implementation of sea turtle conservation regulations under the ESA and continued authorization of the Southeast U.S. shrimp fisheries in federal waters under the MSFCMA were not expected to cause an appreciable reduction in likelihood of survival and recovery of Kemp’s ridleys in the wild. In April 2012, a preliminary Kemp’s Ridley Stock Assessment Model (KRSAM) was developed by the Planning and Model Development Group (PMDG) of LGL Ecological Research Associates, Inc. (Bryan, TX), presented for proof-of-concept review at a stakeholders meeting held at Texas A&M University in May 2012, and improved during a Kemp’s Ridley Stock Assessment Workshop (KRSAW) held in Houston, TX in November 2012 (Gallaway et al. 2013). The overarching objectives of the KRSAW, funded by Gulf States Marine Fisheries Commission (GSMFC), were to examine Kemp’s ridley population’s status, trends and temporal-spatial distribution in the Gulf of Mexico, to estimate mortality attributed to incidental capture in shrimp trawls (under a working hypothesis that shrimp trawling was the only source of anthropogenic mortality in post-pelagic life stages), and to estimate total mortality (Gallaway et al. 2013). The KRSAM raised the bar for demographic modeling of the Kemp’s ridley population, primarily by incorporating (1) a time series of annual shrimp trawling mortality, estimated from a time series of annual shrimp trawling effort by the U.S. shrimping fleet in the Gulf of Mexico, and (2) a growth analysis based on a combination of mark-recapture and carapace length-frequency data combined. No previous demographic model of a sea turtle population had incorporated a time series of shrimp trawling mortality (Gallaway et al. 2013; Caillouet 2014) despite the finding by Magnuson et


al. (1990) that incidental capture in shrimp trawls was the most important source of mortality for post-pelagic sea turtles. The KRSAM needs further improvement, especially by combining a compatible time series of annual shrimp trawling effort by Mexico's shrimping fleet with that of the U.S. shrimping fleet, so that a time series of annual shrimp trawling mortality throughout the Gulf of Mexico can be estimated (Gallaway et al. 2013). For this purpose, we hope that a compatible time series of annual shrimp trawling effort by Mexico’s shrimping fleet can be provided by Mexico’s Comisión Nacional de Acuacultura y Pesca (CONAPESCA; www. conapesca.sagarpa.gob.mx/wb/cona/conapesca_english_version), within the Secretaría de Agricultura, Ganadería, Desarrollo Rural, Pesca y Alimentación (SAGARPA; see NMFS et al. 2011). Demographic modeling has contributed to an understanding of Kemp’s ridley population dynamics, and it may contribute to elucidation of the cause(s) of interruption of exponential growth of the population in 2010. Caillouet (2006, 2010, 2011, 2014) and Gallaway et al. (2013) discussed data and analyses needed for demographic modeling of the Kemp’s ridley population. However, proprietary issues surrounding data can sometimes complicate, delay, constrain, or prevent timely access to data essential to analyses and demographic modeling (Bjorndal et al. 2011). NOAA’s Natural Resource Damage Assessment (NRDA) may provide data relevant to demographic modeling. Data archived in Mexico and the U.S., that heretofore may have been too voluminous to enter into computer compatible media or analyze, may also be useful to improving estimates of population vital statistics needed for demographic modeling. There is a continuing need to identify sources of data, to share data, and to evaluate their usefulness and application to demographic modeling (National Research Council 2010). We suggest that modification of the recovery plan identify and include requirements for data security, sharing, and evaluation (see Bjorndal et al. 2011) as recovery priorities. The National Research Council (2010) recommended that NMFS and USFWS develop a coherent strategy for sea turtle assessments to improve data collection methods, data quality, and data availability, as well as a rigorous plan for external review of data and models used to assess population status and trends. It also recommended research emphasizing estimation of vital rates, ecological or environmental mechanisms that drive vital rates, anthropogenic mortality, and abundance. In-water abundance, hatchling-cohort production, survival of immature turtles and nesting females, age at maturity, breeding rates, and clutch frequency were listed as the most serious demographic data gaps. Identification and protection of migratory corridors and critical habitats are also important to Kemp’s ridley recovery (NMFS et al. 2011; www.nmfs.noaa.gov/pr/pdfs/petitions/ kempsridley_criticalhabitat_feb2010.pdf). In April 2014, the 34th Annual Symposium on Sea Turtle Biology and Conservation was held in New Orleans, Louisiana (Valverde 2014). It included Kemp’s ridley presentations or posters on assessment modeling, change in population growth rate, strandings, migration corridors, incidental hooking associated with recreational fishing in Mississippi, genetic characteristics of feeding aggregations of subadults, brevetoxin exposure, behavior related to red tide, female-biased sex ratios, sex of hatchlings, monitoring and protection of the Tecolutla (Mexico) beach, Tecolutla beach temperatures, and climate change and reproduction. In November 2014, the Second International Kemp’s Ridley Sea Turtle

Symposium, co-hosted by Texas Sea Grant and Gladys Porter Zoo, was held in Brownville, Texas USA (http://texasseagrant.org/assets/ uploads/resources/14-101_SIKRSTS_program.pdf), to provide a forum for presentation and discussion of the many recent advances in Kemp’s ridley science, conservation, and management, and of how these advances impact understanding of Kemp’s ridley biology and conservation. During her presentation at this symposium, Carole Allen stated that the recovery plan is obsolete and should be rewritten (Carole Allen, pers. comm., January 2015). Gulf of Mexico ecosystem changes were among the topics covered by the 2015 Oil Spill and Ecosystem Science Conference, held in February 2015 in Houston, Texas (http://texasseagrant.org/assets/uploads/ resources/15-101_Monitoring_Status_program.pdf). In recent years, USFWS has cut its annual funding for Kemp’s ridley conservation in Tamaulipas, Mexico (Plotkin & Bernardo 2014). NMFS et al. (2011) designated “lack of funding” as a threat. The Kemp’s Ridley Recovery Team “felt strongly that the lack of funds should be highlighted as a potential factor that could reverse the population growth of the Kemp’s ridley” (ibid.). Restoration of funding and increased funding are urgently needed to support Kemp’s ridley conservation, monitoring, research, and demographic modeling. Not only does the recovery plan need modification in 2015, but consideration should again be given to identifying and designating Kemp’s ridley critical habitats, especially in light of the environmental pollution catastrophe that occurred in the Gulf of Mexico in 2010 (http://www.nmfs.noaa.gov/pr/pdfs/petitions/ kempsridley_criticalhabitat_feb2010.pdf). Acknowledgements. We are grateful for the contributions of William Gazey, Pamela Plotkin, Scott Raborn, and John Cole, who served with two of us (BJG & CWC) on LGL’s PMDG, to all participants and observers at the KRSAM stakeholders meeting, and to all participants in the KRSAW (see Gallaway et al. 2013). We greatly appreciate encouragement and support that led to the KRSAW, provided by Louisiana Department of Wildlife and Fisheries (Mark Schexnayder), Sea Grant programs of Texas, Louisiana, Mississippi-Alabama, and Florida (Pamela Plotkin, Charles Wilson, LaDon Swann, and Karl Havens, respectively), and for funding of the KRSAW by GSMFC (Jeffrey Rester). Data for the KRSAM and permission to use them were provided by the NMFS Galveston Laboratory (James Nance), Mexico’s CONANP and Secretaría de Desarrollo Urbano y Medio Ambiente (SEDUMA) (coordinated by Jaime Peña and Patrick Burchfield, Gladys Porter Zoo), the NMFS STSSN (Wendy Teas and Sheryan Epperly), and the CMTTP (Peter Eliazar, Archie Carr Center for Sea Turtle Research, University of Florida), for which we are grateful. Mark Schexnayder, Julia Lightner, and Carole Allen reviewed an early draft, and offered helpful comments. Special thanks to Lisa Belskis for providing information related to the sea turtle symposium in New Orleans. ANTONIO, F.J., R.S. MENDES & S.M. THOMAZ. 2011. Identifying and modeling patterns of tetrapod vertebrate mortality rates in the Gulf of Mexico oil spill. Aquatic Toxicology 105: 177-179. BELTER, C. 2014. Deepwater Horizon: A Preliminary Bibliography of Published Research and Expert Commentary. NOAA Central Library Current References Series No. 2011-01. 81pp. www. lib.noaa.gov/researchtools/subjectguides/dwh_bibliography.pdf


BEVAN, E., T. WIBBELS, B. M.Z. NAJERA, M.A.C.MARTINEZ, L.A.S.MARTINEZ, D.J.L.REYES, M.H.HERNANDEZ, D.G.GAMEZ, L.J. PENA & P.M. BURCHFIELD. 2014. In situ nest and hatchling survival at Rancho Nuevo, the primary nesting beach of the Kemp’s ridley sea turtle, Lepidochelys kempii. Herpetological Conservation and Biology 9: 563-577. BJORNDAL, K.A., B.W. BOWEN, M. CHALOUPKA, L.B. CROWDER, S.S. HEPPELL, C.M. JONES, M.E. LUTCAVAGE, D. POLICANSKY, A.R. SOLOW & B.E. WITHERINGTON. 2011. Better science needed for restoration in the Gulf of Mexico. Science 331: 537-538. Bjorndal, K.A., J. Parsons, W. Mustin & A.B. Bolten. 2014. Variation in age and size at sexual maturity in Kemp’s ridley sea turtles. Endangered Species Research 25: 57-67. BURCHFIELD, P.M. & L.J. PEÑA. 2010. Report on the Mexico/ United States of America population restoration project for the Kemp’s ridley sea turtle, Lepidochelys kempii, on the coasts of Tamaulipas, Mexico 2010. Gladys Porter Zoo, Brownsville, TX. 12 pp. CAILLOUET, C.W., JR. 2006. Guest editorial: revision of the Kemp’s ridley recovery plan. Marine Turtle Newsletter 114: 2-5. CAILLOUET, C.W., JR. 2010. Editorial: demographic modeling and threats analysis in the draft 2nd revision of the bi-national recovery plan for the Kemp’s ridley sea turtle (Lepidochelys kempii). Marine Turtle Newsletter 128: 1-6. CAILLOUET, C.W., JR. 2011. Guest editorial: Did the BPDeepwater Horizon-Macondo oil spill change the age structure of the Kemp’s ridley population? Marine Turtle Newsletter 130: 1-2. Caillouet, C.W., Jr. 2012a. Editorial: Do male-producing Kemp’s Ridley nesting beaches exist north of Tamaulipas, Mexico? Marine Turtle Newsletter 134: 1-2. Caillouet, C.W., Jr. 2012b. Editorial: Does delayed mortality occur in sea turtles that aspirate seawater into their lungs during forced submergence or cold stunning? Marine Turtle Newsletter 135: 1-4. CAILLOUET, C.W., JR. 2014. Interruption of the Kemp’s ridley population’s pre-2010 exponential growth in the Gulf of Mexico and its aftermath: one hypothesis. Marine Turtle Newsletter 143: 1-7. CAILLOUET, C.W., JR., D.J. SHAVER & A.M. LANDRY, JR. In press. Kemp’s ridley sea Turtle (Lepidochelys kempii) head-start and reintroduction to Padre Island National Seashore, Texas. Herpetological Conservation and Biology. CAMPAGNA, C., F.T. SHORT, B.A. POLIDORO, R. MCMANUS, B.B. COLLETTE, N.J. PILCHER, Y. SADOVY DE MITCHESON, S.N. STUART & K.E. CARPENTER. 2011. Gulf of Mexico oil blowout increases risks to globally threatened species. BioScience 61: 393-397. Coleman, A.T. 2013. Evidence of long distance homing in a displaced juvenile Kemp’s ridley sea turtle (Lepidochelys kempii). Marine Turtle Newsletter 137: 10-12. CROWDER, L. & S. HEPPELL. 2011. The decline and rise of a sea turtle: how Kemp’s ridleys are recovering in the Gulf of Mexico. Solutions 2: 67-73. FIKES, R., L. MCCORMICK, D.B. INKLEY & S. GONZALEZ-

ROTHI KRONENTHAL. 2014. Four years into the Gulf oil disaster: still waiting for restoration. National Wildlife Federation, Merrifield, VA.19 pp. www.nwf.org/~/media/PDFs/water/2014/ FINAL_NWF_deepwater_horizon_report_web.pdf Finkbeiner, E.M., B.P. Wallace, J.E. Moore, R.L. Lewison, L.B. Crowder & A.J. Read. 2011. Cumulative estimates of sea turtle bycatch and mortality in USA fisheries between 1990 and 2007. Biological Conservation 144: 2719-2727. GALLAWAY, B.J. & C.W. CAILLOUET, JR. 2014. The 2013 Kemp’s ridley stock assessment: shrimp trawls and oil spills. In: Texas Sea Grant Program. Second International Kemp’s Ridley Sea Turtle Symposium. TAMU-SG-14-101. College Station, TX. p. 10. http://texasseagrant.org/assets/uploads/resources/14-101_ SIKRSTS_program.pdf GALLAWAY, B.M. & W.J. GAZEY. 2014. The 2014 Kemp’s ridley stock assessment: reduced nesting or reduced nesters? In: Texas Sea Grant Program. Second International Kemp’s Ridley Sea Turtle Symposium. TAMU-SG-14-101. College Station, TX. p. 11. GALLAWAY, B.J., C.W. CAILLOUET, JR., P.T. PLOTKIN, W.J. GAZEY, J.G. COLE & S.W. RABORN. 2013. Kemp’s ridley stock assessment project. Final Report from LGL Ecological Research Associates, Inc. to Gulf States Marine Fisheries Commission, Ocean Springs, MI. 291 pp. www.gsmfc.org/publications/ Miscellaneous/Kemp%20Ridley%20Stock%20Assessment%20 Report%20Final%20June%2027%202013.pdf GARRISON, L.P. & C. SASSO. 2012. The movement and habitat associations of sea turtles in the northern Gulf of Mexico. NMFSSEFSC. 12 pp. http://www.boem.gov/uploadedFiles/BOEM/ BOEM_Newsroom/Library/Publications/2012/PowerPoint_ Source_Files/2F_0215_Garrison_PPT.pdf HEPPELL, S.S. In press. Data and models indicate dramatic changes in Kemp’s ridley growth rate. Proceedings of the 34th Annual Symposium on Sea Turtle Biology and Conservation, New Orleans, LA. HEPPELL, SS. 2014. The fragility of recovery: implications of the dramatic reduction of the Kemp’s ridley population growth rate since 2010. In: Texas Sea Grant Program. Second International Kemp’s Ridley Sea Turtle Symposium. TAMU-SG-14-101. College Station, TX. p. 9. LEWISON, R., B. WALLACE, J. ALFARO-SHIGUETO, J.C. MANGEL, S.M. MAXWELL & E.L. HAZEN. 2013. Fisheries bycatch of marine turtles: lessons learned from decades of research and conservation. In: Wyneken, J., K.J. Lohmann & J.A. Musick (Eds.). The Biology of Sea Turtles, Volume 3. CRC Press, Boca Raton, FL. pp. 329-351. MAGNUSON, J.J., K.A. BJORNDAL, W.D. DUPAUL, G.L. GRAHAM, D.W. OWENS, C.H. PETERSON, P.C.H. PRITCHARD, J.I. RICHARDSON, G.E. SAUL & C.W. WEST. 1990. Decline of the sea turtles: causes and prevention. National Research Council Committee on Sea Turtle Conservation, National Academy Press, Washington, DC. 259 pp. NMFS. 2010. Interim Endangered and Threatened Species Recovery Planning Guidance Version 1.3. National Marine Fisheries Service, Silver Spring, MD. 122 pp.


NMFS & USFWS. 2007. Kemp’s ridley sea turtle (Lepidochelys kempii) 5-yr review: summary and evaluation. National Marine Fisheries Service, Silver Springs, MD, and U.S. Fish and Wildlife Service, Albuquerque, NM. 50 pp. NMFS, USFWS & SEMARNAT. 2011. Bi-national recovery plan for the Kemp’s ridley sea turtle (Lepidochelys kempii). Second Revision. National Marine Fisheries Service. Silver Spring, MD. 156 pp. National Research Council. 2010. Assessment of Sea-Turtle Status and Trends: Integrating Demography and Abundance. National Academies Press, Washington, DC. 162 pp. PLOTKIN, P. & J. BERNARDO. 2014. Sea turtle funding dries up. Science 343: 484. PUTMAN, N.F., K.L. MANSFIELD, R. HE, D.J. SHAVER & P. VERLEY. 2013. Predicting the distribution of oceanic-stage Kemp's ridley sea turtles. Biology Letters 9: 20130345. Putman, N.F., R. Scott, P. Verley, R. Marsh & G.C. Hays. 2012 Natal site and offshore swimming influence fitness and long-distance ocean transport in young sea turtles. Marine Biology 159: 2117-2126. Putman, N.F., T.J. Shay & K.J. Lohmann. 2010. Is the geographic distribution of nesting in the Kemp's ridley sea turtle

shaped by the migratory needs of offspring? Integrative and Comparative Biology 50: 305-314. SAFINA, C. 2011. The 2010 Gulf of Mexico oil well blowout: a little hindsight. PLoS Biol 9(4): e1001049. http://journals.plos. org/plosbiology/article?id=10.1371/journal.pbio.1001049 SARTI, L., M. MARTINEZ, B. ZAPATA & L. GERARDO CARDENAS. 2014. 2014 Kemp’s ridley nesting in Tamaulipas, Mexico – Rancho Nuevo, Barra del Tordo, Altamira, and Ciudad Madero. In: Texas Sea Grant Program. Second International Kemp’s Ridley Sea Turtle Symposium. TAMU-SG-14-101. College Station, TX. p. 6. Seney, E.E. & A.M. Landry, Jr. 2008. Movements of Kemp’s ridley sea turtles nesting on the upper Texas coast: implications for management. Endangered Species Research 4: 73-84. Smith, L.C., Jr., L.M. Smith & P.A. Ashcroft. 2011. Analysis of environmental and economic damages from British Petroleum’s Deepwater Horizon oil spill. Albany Law Review 74.1: 583-585. Valverde, R.A. 2014. Report: 34th Annual Symposium on Sea Turtle Biology and Conservation, 10-17 April 2014, New Orleans, USA. Marine Turtle Newsletter 142: 20-22.

Radio Frequency Identification Technology and Marine Turtles: Investigation of Passive Integrated Transponder (PIT) Tags and Readers Sheryan P. Epperly, Lesley W. Stokes* & Lisa C. Belskis

NOAA, National Marine Fisheries Service, 75 Virginia Beach Dr., Miami, FL 33149 USA (E-mail: [email protected]; [email protected]; [email protected]) *corresponding author

The insertion of a Passive Integrated Transponder (PIT) tag into marine turtles provided one of the first means of permanent marking, and today the tags are used widely. PIT tags, also known as a Radio Frequency Identification (RFID) tags, are not subject to tag loss in the same way that external flipper tags are (but see McNeill et al. 2013), and therefore they provide a mechanism to track recaptures throughout the turtle’s lifespan. Data obtained through recaptures can provide valuable scientific information regarding growth, movement patterns, incidental fishery interactions, and survival. As Radio Frequency Identification technology developed for use in many industries, PIT tag and PIT tag reader options also increased, resulting in compatibility issues that have complicated the ability of researchers to identify animals tagged by other investigators. If researchers are not aware of the incompatibilities that exist within this technology, there is a greater risk that opportunities to identify previously tagged turtles could be lost, along with the scientific value that those rare encounters provide. The purpose of this paper is to explain the basics of RFID technology (e.g., PIT tags) as applied to marine turtles, point out inconsistencies in the use of this technology by researchers using western North Atlantic leatherbacks, Dermochelys coriacea, as an

example, and provide some guidance for future use. The technology is complex and here we barely brush the surface; books have been written on the subject (e.g., Garfinkel & Rosenberg 2006). Certain technical terms used are defined at the end of the paper and are in bold type at first use. For wildlife marking, there are three elements of an RFID system: the transponder (PIT tag) and the transceiver (PIT tag reader), both with antennas and specific radio frequency characteristics, and the database of assigned tag ID numbers and associated data. The transceivers used by marine turtle researchers are portable. Tags used for marine turtles are passive, deriving all their power from the incoming radio frequency (RF) signal from the reader. Tags used for marking animals today are excited in the low frequency (LF) bandwidth of 125-134.2 kHz with a wavelength of 2,400 m (Garfinkel & Holtzman 2006). A variety of tags have been used in marine turtles, but all have been full-duplex (FDX, versus halfduplex, HDX). The tag's small integrated circuit (microchip), which is attached to its antenna (Fig. 1), is energized by a reversing magnetic field of RF energy from the reader (the excite field). The tag transfers a binary signal of the unique ID, programmed by the manufacturer, to the reader. This is done by perturbing the excite


Figure 1. Passive Integrated Transponders (PIT tags) were tested in 3 different orientations, which placed a tag’s antenna in different positions relative to the plane of the readers’ antennas. Often the end of the tag with the microchip is obscured by epoxy internal to the capsule. field from the reader; the data modulation protocol of the tag determines the response frequency. The reader recognizes the data modulation protocol, decodes the information, and sends the ID to a display. In some readers, the information may also be stored in the reader memory for future access. Initially, researchers matched their readers to their selected tag's excite frequency, modulation, etc. Today more manufacturers are offering multi-mode readers that enable the detection and reading of some or all the tag types used for the permanent marking of marine turtles. However, there still are many single-mode readers in use among turtle researchers. Tags that have been used in marine turtles are "promiscuous," capable of responding to any reader with the appropriate excite frequency range and readable if the reader recognizes the data modulation protocol. The earliest tags used for marine turtles were 400 kHz (FDX-A; e.g., Fontaine et al. 1993), then 125 kHz (FDX-A) and 128 kHz (FDX-A) tags were used. Most recently, 134.2 kHz

tags (FDX-B) have been deployed. In addition, some Caribbean leatherback researchers initially used secure (encrypted) tags from the distributor AVID (e.g., McDonald & Dutton 1996). While compatible in frequency (125 kHz) and read protocols with many readers in use, the decryption capability initially was available only on AVID readers. Unfortunately, other readers, even those of the same excite field range and modulation protocols, could not read encrypted tag. Much has been written about tag-reader incompatibilities, especially in light of the use of RFID technology in companion animals (e.g., pets; World Small Animal Veterinary Association 2012). In response, the International Organization for Standardization (ISO) issued Standards 11784 and 11785 (ISO 1996a,b). Those standards specify the ID code structure (ISO 11784), how the transponder is activated, and how the stored information is transferred to the transceiver (ISO 11785). An ISO tag's excite field frequency is 134.2 ±13.42x10-3 kHz, and it is becoming the standard tag used for companion animals worldwide and by marine turtle researchers. The ISO tag is available from most manufacturers, and for some manufacturers, this is the only tag now being marketed for use in wildlife. A factor affecting the ability to excite and read a compatible tag is the reader's near-field read distance, which is a function of excite field strength, read antenna circuitry, and software. Read distance is especially important for leatherback turtles that historically have been tagged in the neck or shoulder area, where the needle usually is inserted perpendicular to the surface, placing the tag as deep as 4 cm (the length of the longest insertion needle in use by marine turtle researchers). A tag implanted beyond the read distance of a tagreader combination cannot be detected. Tags implanted in nesting females on the beach may be within the transceiver’s read distance capability at the time, but when the turtle returns to foraging grounds, fatty tissue underneath the skin surface may thicken (Davenport et al. 2011). A more robust body condition, particularly with leatherback turtles, effectively increases the required read distance, and may increase the potential that the tag might not be detected if the turtle is encountered away from the nesting beach. These issues (tag-reader incompatibility, encrypted tags, and read distances) have serious ramifications for the use of PIT tags in marine turtle research. For example, a single-mode reader may activate a tag within its excite field range, but will not be able to read the ID unless it recognizes the data modulation protocols of the tag's response. This means that if an animal is tagged and then moves to a different researcher's study area, the original tag may not be detected unless the second researcher is using a reader that is compatible with the original

Figure 2. Portable RFID readers tested: Trovan GR-251 and LID-500, AVID Power Trackers and MiniTracker, and Destron Fearing Handi Reader, Mini Portable Reader, Pocket Reader, and Pocket Reader EX. Marine Turtle Newsletter No. 145, 2015 - Page 5

Location French Guiana, Suriname, Guyana

Venezuela

Costa Rica

USA

Canada

PIT tags applied Readers used Sources Comments SOUTH AMERICA: Not PIT tagging or scanning in Brazil (J. Tome) or Colombia (D. Amorocho) Trovan LID500; L. Kelle, M. Tested a modified Trovan reader (unsatisfactory); Trovan ID100 Destron Pocket Hilterman, E. tested AVID Power Tracker IV (unreliable at 128 kHz Reader EX tested Goverse, P. Pritchard reading Trovan tags); tested a Destron Pocket 2005 & A. Narain Reader (did not detect 90% of Trovan tags) AVID unencrypted 125 kHz; AVID Power H. Guada & S. AVID encrypted Tracker IV Eckert 125 kHz CENTRAL AMERICA: Not PIT tagging or scanning in Panama (D. Chacon) AVID unencrypted AVID Tracker II D. Chacon Gandoca and Black Beach 125 kHz and IV AVID encrypted Reserva Pacuare; Not PIT tagging or scanning at AVID Tracker III I. Abella Gutierrez 125 kHz Tortuguero (S.Troėng) NORTH AMERICA: Not PIT tagging or scanning in México (L. Sarti) NOAA Fisheries SEFSC and NEFSC research and Destron Pocket S. Epperly, H. Haas, L. Belskis, K. observer programs; STSSN; Juno Beach nesting Reader and Dodge, C. Johnson & beach project; researchers are upgrading software Pocket Reader version K.Stewart EX Destron 125 kHz AVID VAMSM has an AVID MiniTracker for their STSSN MiniTracker C. Trapani activities Multi-Mode AVID unencrypted 125 kHz; Destron Pocket Archie Carr NWR; using older software version, but D. Bagley Destron 125 kHz Reader likely will upgrade (future) AVID Power AVID unencrypted Tracker IV (thru 125 kHz 2002-04; 2002); AVID M. James Has detected Trovan tags released from Guianas AVID encrypted Power Tracker prior to 2002 VI since 2003 CARIBBEAN: Not PIT tagging or scanning in Grenada (C. Lloyd)

British VI

AVID unencrypted 125 kHz

Destron Pocket Reader

USVI

AVID unencrypted 125 kHz; AVID encrypted in early years

AVID Power P. Dutton & R. Tracker II and IV Boulon

Puerto Rico


C. Diez & P. Dutton; AVID Power H. Horta is another Tracker II and IV contact

S. Gore & B. Godley

Reader has older software version (218-S53)


Location

PIT tags applied

PIT readers used

Source

Comments

Trinidad & Tobago


AVID Power Tracker II and IV

S. Eckert & D. Sammy

Anguilla

Destron 134.2 kHz (IdentiChip)

Destron Pocket Reader

J. Gumbs & B. Godley

Likely reader has older software version (218-S53) as supplier same as for BVI

Gabon

Trovan ID100 128 kHz

Trovan LID-500

E. Goverse

Tagging in neck

AFRICA

Table 1. Table begins on page 6. Passive Integrated Transponders (PIT) and readers used in leatherback projects in the West Atlantic Ocean and in Gabon through December 2004. Note that additional readers have since become available, and may be in use now, but this table does not reflect the changes made since the survey. For example, the French Guiana researchers also now use Trovan’s GR-251 reader and Trinidad researchers now use Destron-Fearing Pocket Reader EX models. See Tables 2 and 3 for what was available as of December 2012. data modulation protocols. Besides the lost opportunity to detect a marked turtle, the unnecessary implanting of an additional tag may result in interference with the original tag when energized (Garfinkel & Holtzman 2006; see discussion below). In most instances, a reader would display the tag presenting the stronger signal. Similarly, an encrypted tag may not be detected or read, or may not be decrypted, leading to the inability to identify a marked animal. Lastly, the nearfield read distance needed for leatherbacks may be greater than the capability of some portable readers to detect a tag. Leatherback turtles are perhaps the most far-ranging of all sea turtles species, mainly living a pelagic life, except for brief times when females are nesting or migrating through coastal waters (Turtle Expert Working Group 2007). An informal survey of virtually all North Atlantic leatherback researchers and of the U.S. Atlantic coast Sea Turtle Stranding and Salvage Network indicated that many different tag types and readers were in use at the end of 2004 (Table 1), and that incompatibilities likely existed. We compiled information about each of the tags (Table 2) and readers (Table 3) used by those surveyed. We tested each combination of tag and receiver for compatibility and read distance. Furthermore, we also

tested new readers available after the survey was conducted. Similar studies have been conducted for tags and readers commonly used for companion animals (Lord et al. 2008a,b; see also www.rfidnews. com/GeneralRFIDNews/reader-evaluation/assets/Evaluation.pdf). Lastly, we discuss our results in light of the 2004 snapshot survey, provide information on what equipment was available 8 years later (December 2012; see Tables 2 and 3), and provide guidance to sea turtle researchers for the future. We tested all seven types of RFID tags that were in use by marine turtle researchers at the time of the survey: AVID's 125 kHz encrypted and non-encrypted, and 134.2 kHz; Destron Fearing's (Destron) 125 kHz, 134.2 kHz, and 400 kHz; Trovan's 128 kHz (Table 2). We also tested eleven different reader models: AVID's Power Tracker II, IV, V, VI and MiniTracker; Destron's Handi Reader, Mini Portable Reader, Pocket Reader, and Pocket Reader EX; Trovan's LID-500 and GR-251 (Fig. 2, Table 3]. For each of the seven tag types, we tested three replicates (e.g., three individual tags with unique IDs), each in three different orientations (antenna up, antenna down, and flat, see Fig. 1), yielding nine readings for each reader for each tag type. Except for Trovan's LID-500 and Destron’s Mini Portable Reader and Handi Reader, all units were supplied directly by the manufacturer and had not seen field use. We found that battery charge was important and, thus, we always maintained freshly charged batteries in the units. Trials were conducted on a wooden table, and all metal objects in close proximity to the testing station were removed to minimize interference (the experimental arena is depicted in Fig. 3). Each tag, secured within a plastic sleeve to achieve the necessary orientation, was placed on a base consisting of one ~3.2 mm deep vinyl tile and a second vinyl tile with a center well cut out to accommodate the tag. Two ceramic 4 x 4 inch tiles were stacked in each

Figure 3. The experimental arena. The tag was placed in the red plastic cylinder to control the tag’s position and orientation (see Fig. 1) and placed on a vinyl tile. Two ceramic spacers elevated the vinyl tiles that were stacked over the tag.


Manufacturer

Model

Frequency EN

Allflex USA, Inc.1

GPT12

134.2 kHz No

Encrypted A2028/A2024

125 kHz

Yes

AVID Identification Systems, Inc. Unencrypted 125 kHz No (AVID); Single Use A2128/A2124 Disposable Syringe/ Disposable Needle Assembly ISO compliant 134.2 kHz No A2328/A2324 BIOMARK1

Trovan

HPT12

134.2 kHz No

TX1400L TX1440L* TX1406L** TX1405

125 kHz

ISO compliant TX1410BE TX1415BE TX1400ST TX1440ST*

134.2 kHz No

TX1400A

400 kHz

No

ID 100 supplied in cannula needle 128 kHz ID 100A supplied in bulk

No

ID 162

No

134.2 kHz No

Tag Size

Comments ISO FDX-B compliant (manufacturer 12 x 2.1 mm code is 982); decimal: 15 digit code, hexadecimal: 13 character code 12 x 2.1 mm 9-digit code (000*000*000) FECAVA (EuroCode); 10-characrter unencrypted code, 9 digits followed by 12 x 2.1 mm “A” (000*000*000A on AVID readers and 000000000A on Destron readers) ISO FDX-B compliant (manufacturer 12 x 2.1 mm code is 977); decimal: 15 digit code, hexadecimal: 13 character code2 ISO FDX-B compliant (manufacturer 12 x 2.1 mm code is 989); decimal: 15 digit code, hexadecimal: 13 character code2 12 x 2.1 mm FECAVA3; 10 hexadecimal characters (e.g., 12 x 2.1 mm 442F664C1D), no longer distributed in the 12 x 2.1 mm USA for fish and wildlife applications 14 x 2.1 mm ISO FDX-B compliant (manufacturer code is 985); decimal: 15 digit code, 2 20 x 3.1 mm hexadecimal: 13 character code ; no longer 23 x 3.4 mm distributed in the USA for fish and wildlife 12 x 2.1 mm applications 12 x 2.1 mm sold under several names, such as IdentiChips in the UK *sterile wrapped for syringe implanter 10 hexdecimal character code (e.g., 526F39503C), this frequency was once used 12 x 2.1 mm for marine turtles, but read distance is short; discontinued Not distributed in USA; endorsed by IUCN Captive Breeding Specialist Group Distributed in USA; same transponder 11.5 x 2.12 as ID100, but not in a needle; normal mm decimal display is 2 digits-4 hexadecimal characters-4 hexadecimal characters (e.g., 00-06C0-B9AD) ISO FDX-B compliant (manufacturer 11.5 mm x code is 956); decimal: 15 digit code, 2.12 mm hexadecimal:13 character code2; not distributed in USA

Table 2. Portable PIT tag readers used by or available to most marine turtle researchers as of December 2012. Tags tested are in bold font. xcept for the AVID Encrypted A2028/A2024 tags all other available tags are not encrypted. EN = Encrypted. 1Biomark is the exclusive distributor for Allflex, BIOMARK, and Destron Fearing products in the United States. 2 Most portable PIT tag readers are set to display the decimal code. 3FECAVA = Federation of European Companion Animal Veterinarian Association.


Figure 4. The average and the range of read depth readings for each reader/ tag combination. Readers were tested with three tags of each type, with each tag in three different orientations, yielding 9 read depth readings for each reader tested. The readers tested were AVID’s Power Tracker II (A-PTII), IV (A-PTIV), V (A-PTV), VI (A-PTVI), and their multi-mode MiniTracker (AMT); Trovan’s LID-500 (T-LID500) and GR-251 (T-GR251); Destron’s Handi Reader (D-HR), Mini Portable Reader (D-MPR), Pocket Reader (D-PR), and Pocket Reader EX (D-PREX). Raw data are available from corresponding author on request or from the Southeast Fisheries Science Center website at http://www.sefsc.noaa.gov/ turtles/PR_Epperly_etal_2015_MTN_ Supplement.pdf

corner to allow space for the tag to be placed on end and support the stack of vinyl tiles on top. For each trial, additional vinyl tiles were stacked over the base in order to systematically increase the distance between the tag and the reader; he tag was scanned by moving the reader across the surface of the top tile. This process was repeated until the reader no longer could read the tag's ID. The top tile was then removed, and the tag was scanned until detecting the tag three consecutive times. The final tile depth was measured with aluminum slide calipers to the nearest 0.1 cm and recorded. Measurements were adjusted to account for the thickness of the supporting bottom tile by subtracting 3.2 mm, and for the distance to the center of the tag by subtracting ½ the length or width of the tag depending on tag orientation; the tags were measured using dial calipers to the nearest 0.1 mm. From the data pooled for all tag replicates and tag orientations per reader, the minimum and maximum adjusted measurements were determined, and a mean read depth was computed. Read Distance. The greatest read distance almost always occurred when the tag was oriented with its axis perpendicular to the plane of the reader's antenna, with the tag's antenna oriented upward toward the reader (Fig. 1). While there was little difference between the antenna-up or antenna-down orientation (usually 200) of the captive-reared loaner turtles in the Sea Life Park program have been released as part of the July 4th “Turtle Independence Day” celebration at the Mauna Lani Bay Resort on the South Kohala Coast of the island of Hawaii (Balazs et al. 2002). However, starting in 1998, post-hatchling turtles born at Sea Life Park were sent to the Maui Ocean Center at Ma'alaea on the island of Maui. A total of 48 healthy and robust juveniles have thus far been PIT tagged and released into Maui's nearshore waters. Four of these turtles, ranging from 2.5-4.0 years in age, 45-56 cm SCL, and weighing 14.1-25.4 kg were equipped with carapace-mounted Telonics satellite tags. Straight carapace length (SCL) was measured to the nearest 0.1 cm and flipper tags and PIT tags were inserted into the hind flippers. Argos satellite-linked transmitters (model ST-24 manufactured by Telonics, Inc., Mesa, AZ) were attached to four juvenile green Argos ID

SCL (cm)

Tag nos.

Release age

WT (kg)

turtles between 2003 and 2006. Transmitters were attached to the turtle’s carapace safely and securely with polyester surfboard resin and fiberglass cloth following the procedures used in Balazs et al. (1996) with the size and placement of the fiberglass strips modified for the smaller transmitter size. Transmitters were programmed with a duty cycle of 12 hours on and 48 hours off. Units were turned on at a time computed to synchronize with optimum satellite overpass coverage. The raw Argos data were processed by CLS using least squares analysis. Only positional data were collected with data and estimates of location accuracy provided by Argos (CLS-America, Inc., www.argos-system.org). Data were then assessed and positions were considered unacceptable if: 1) they were located on land, 2) the speed of travel between two locations was over 5 km/hr, or 3) the position made a turn greater than 90 degrees in less than a 24 hr period. Decisions for excluding a position were rigorously based on these criteria. The best daily location and the great circle equation with the WGS84 ellipsoid were used to compute distance traveled (Bowditch 1995). When available, location classes (LCs) of 1, 2, or 3 were used for distance calculations; when unavailable, distance was calculated using positions closest to noon UTC (Coordinated Universal Time) after unacceptable positions had been removed. The final location of a track was determined either by the last Argos position or when positional locations clustered in one general area for more than 1 month. The earliest date at an end point was considered the end date for distance calculations. Maps were created for each turtle using the Generic Mapping Tools program developed by Wessel & Smith (2014) following procedures of Ellis & Balazs (1998). Tracking durations for the four turtles ranged from 267-481 days (Table 1, Figs. 1-4). The 2003 turtle was set free 11 km south of Maui in the Alenuihāhā Channel, while the other three turtles were released