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Figure 1. Map of North Atlantic Ocean, showing the initial capture, tag, and release sites of loggerheads P9487/P9488 (square with cross symbol) and P8001/P8002 (circle with cross symbol); the recapture site of P9487/P9488 (open square); and the site of pop-up tag release from P8001/P8002 (open circle). Open triangle designates the location of final transmission from a satellite transmitter on a loggerhead released in waters off Madeira, Portugal (Dellinger & Freitas 2000; McCarthy et al. 2010).

Here we report on the movements of two loggerheads from the waters around the Azores that swam to the northwest and either reached or approached Canadian waters. The Archie Carr Center for Sea Turtle Research (ACCSTR) at the University of Florida has had a long-term collaboration with the Departamento de Oceanografia e Pescas of the Universidade dos Açores (DOP) first established by Archie Carr and Helen Martins in the early 1980s and continued to the present by the ACCSTR, DOP, and many valued colleagues in the Azores (Martins et al. 2018). Under this collaboration, more than 4,000 oceanic-stage loggerheads have been tagged with flipper tags by many partners in the Azores including faculty and students of DOP, government officials, commercial fishers, and ecotourism operators.

The loggerhead that reached waters south of the Flemish Cap and east of the Grand Banks was originally tagged through one of our partners, Serge Viallelle owner of Espaço Talassa, a company that conducts ecotourism trips from the island of Pico, Azores, in inflatable vessels. On 18 May 2015, the captain of one of his tour groups captured a loggerhead by hand off the south coast of Pico at 38.34° N, 28.20° W (Fig. 1). The turtle was tagged (P9487/P9488) in each front flipper with Inconel tags (Style 681, National Band & Tag Company, Newport, KY, USA), measured, and released shortly after capture. Minimum curved carapace length (Bolten 1999) was 64.0 cm. This is the size by which most loggerheads have left Azorean waters (Bolten 2003).

On 25 September 2016 (16 months later), the same turtle was incidentally captured on a pelagic longline in Canadian waters south of Nova Scotia at 44.42° N, 60.81° W (Fig. 1). The straight-line distance between the release and recapture sites is approximately 2,800 km. The turtle was carefully brought on board and examined by fishing industry volunteers trained in marine turtle handling protocols. Tag P9488 was still attached, but tag P9487 had been lost. The turtle was not retagged or measured, but was photographed and released (Fig. 2).

Figure 2. Loggerhead P9487/P9488 prior to release from a longline vessel in Canadian waters. Photo taken by Alec Rodgerson.

Figure 3. Loggerhead P8001/P8002 before release with pop-up tag. Photo taken by Marco A. Santos.

A second loggerhead that moved to the northwest was initially caught by a longline fishing boat that was part of an experimental study of the effect of hook types on sea turtle bycatch in the Azores (Bolten et al. 2000). Trained observers tagged (P8001/P8002) and measured (55.6 cm minimum straight carapace length) the loggerhead (Fig. 3). Because the turtle had been only lightly hooked in the lower jaw, it was selected for a study of survival probabilities in which pop-up archival transmitting tags were attached to 25 loggerheads in the North Atlantic (Sasso & Epperly 2007). The loggerhead was captured and released on 2 September 2001 at 38.36° N, 30.91° W. The pop-up tag was released from the live loggerhead at 44.65° N, 44.54° W (Fig. 1) on 15 July 2002, the programmed pop-off date.

The location of the pop-up tag was close to the final transmission site from a satellite transmitter attached to a loggerhead that was released in waters off Madeira, Portugal, in April or May 1998 (Dellinger & Freitas 2000; McCarthy et al. 2010). Its last transmission was at approximately 45.2° N, 42.0° W (Fig. 1).

An understanding of the connectivity among oceanic developmental areas in the high seas is necessary to effectively manage populations of the highly migratory loggerhead (LaCasella et al. 2013; López-Castro et al. 2014). A coordinated effort using all potential tagging techniques and biomarkers (including telemetry, genetics, stable isotopes, trace elements, and flipper tags) and all stakeholders (including commercial and recreational fisheries) is needed.

Acknowledgments. All appropriate permits were obtained for these studies including UF IACUC (Protocol #201701985). We thank the Espaço Talassa sea team members. We are grateful to the Fundacão para a Ciência e a Tecnologia (FCT) for the Post-doc grant (SFRH/BPD/1102942015) attributed to F. Vandeperre, to the COSTA project funded by the Marine Turtle Conservation Fund of the U.S. Fish and Wildlife Service (Agreement number F15AP00577), and to the Disney Conservation Fund for support through the Archie Carr Center for Sea Turtle Research. Current license for tagging in the Azores is from the Direçao Regional do Ambiente (DRA) (Regional Directorate for the Environment). We are grateful to the fishing industry volunteers in Canada who contributed to this work. Research activities in Canada are authorized under SARA scientific permitting and are supported by Fisheries and Oceans Canada and the Canadian Sea Turtle Network. We thank Cathi Campbell for assistance with the figures.

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