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The aim of the 24th RETOMALA meeting was to update our status of knowledge about Hawksbill turtle (Eretmochelys imbricata) in the Latin American region. Our agenda covered 12 talks: two regarding regional status and initiatives, eight with national-level data, and two with local level information (Table 1). The hawksbill turtle (Eretmochelys imbricata) has raised interest and concern for its conservation status, because it is categorized as ‘Critically Endangered - CR’ by the International Union for the Conservation of Nature (IUCN) Red List (Mortimer and Donnelly, 2008).

Table 1. Program of the 24th RETOMALA “Reunión de Especialistas Latinoamericanos en Tortugas Marinas” (Latin American Sea Turtle Specialists Annual meeting). Original title in Spanish (S); Portuguese (P); English (E).

The hawksbill turtle’s status is linked to multiple threats, such as take of individuals for its meat and tortoiseshell, harvest of eggs, habitat loss, and by-catch (Meylan, 1999; Campbell, 2014). It is necessary to reassess status of the hawksbill turtle at a local, national and regional level to adapt their conservation and management actions (Wallace et al. 2010; Liles et al. 2015), especially in Latin America. All the presenters recognised the importance of compiled, analysed, and shared the available information about the current status of hawksbill turtle in the region.

Our meeting started with a welcome speech from the ISTS-38 President Yoshi Matsusawa. He stressed the importance of hawksbill turtles in the Japanese ancient culture, and acknowledged the effort of all RETOMALA’s attendees to be in Japan to participate in our regional meeting.

Presentations descriptive summary (in alphabetical order):

Brazil. The TAMAR Project has managed two important nesting areas for hawksbills: Rio Grande do Norte and Bahia. They have made surveys in both regions and during last four seasons they have counted an average of 2500 nests with higher numbers during January and February (Marcovaldi et al. 2007). Surveys in water are also carried out to study abundance, growth rate and residence time of the species. Assessments of the incidental catch by industrial longline and trawl fisheries have indicated important locations of strandings that must be studied further. Previously published research about hawksbill migrations in and outside Brazil were done using flipper tags and satellite tracking (Marcovaldi et al. 2012).

Costa Rica-Caribbean region. Tortuguero is an important nesting area for sea turtle species. Although the hawksbill turtle is not the most abundant species in this area, its numbers apparently have increased lately and it is unclear whether this reflects increased monitoring and conservation effort on the beaches or shows a true increase in their nesting population. One of the last published studies about hawksbill turtles in Tortuguero was in 1993 and showed a decline of the species (Bjornal et al. 1993). Despite current projections that may indicate an increase in the population, the data are still under review and they do not reach the levels previously reported in 1993. Of note, the relocation, camouflage, monitoring and implementation of protecting networks for nests has been increased to minimize their threats (e. g. looting and predation by raccoons, dogs, and armadillos).

Costa Rica-Pacific region. Since 2009, there has been an ongoing in-water monitoring program based on turtle captures with turtle nets, which was initially stimulated by information provided by artisanal fishermen about the presence of hawksbill turtles in Punta Coyote. Studies carried out with acoustic transmitters suggest that hawksbill turtles commonly use rocky reefs, especially juvenile animals (Carrión-Cortez et al. 2013). In 2017, the project was extended to Cabo Blanco Absolute Nature Reserve, where turtles are captured in rocky pools. These monthly samplings have obtained the largest numbers of captures and recaptures of the project. During 2018, several acoustic transmitters will be placed in the hawksbill turtles captured in Cabo Blanco.

Cuba. Dr. Julia Aranza showed maps of the southern portion of Cuba. She reported that it is possible to observe hawksbill turtles nesting in six different areas. Although hawksbill turtles are commonly reported nesting in the zone, their trends remained unclear. The presentation compiled data from 2001 to 2015.

Curacao. Since 2014, the Sea Turtle Conservation Curacao (NGO) has been conducting volunteer programs with sea turtles. In 2017, the NGO officially began carrying out research, conservation, education and outreach efforts. The goal of this NGO is to protect sea turtles and their habitats, monitoring four sections of the island, both in land and in-water, and doing active stranding response and habitat surveys. Until now, six to ten hawksbill nests have been reported. In the case of in-water assessments, they have involved citizen science by working with photographs provided by local diving operators, and they have been able to identify up to 12 hawksbill turtle residents of the foraging areas through photo-identification of their facial profiles.

Ecuador. The presentation described two approaches in the Galapagos area, referencing historical places where sea turtles were found until 2008. By then, hawksbill turtles were declared ‘critically endangered’ and the population of the Eastern Pacific ‘not viable.’ In-water projects were initiated in 2011 and they were able to identify important hawksbill aggregations using different techniques. Since then, they have tagged different animals and although they have not found nesting of this species in the Galapagos archipelago, they have found hawksbill turtles in the feeding grounds.

Techniques employed in the project include intentional in-water capture and using photographs provided by local volunteer citizen science divers. Many hawksbill turtles have been photo-identified with the help of the I3S software (Dunbar et al. 2014). They have registered hawksbill turtle residents in the area, with two turtles sighted for the first time in 2011 and re-sighted in 2015 and 2016 respectively. The land-based approach in Ecuador has included assessment of organisms in water and sightings of sea turtles that have been released or tagged in continental areas and found in the Galapagos Islands. There was discussion of the presence of possible green and hawksbill turtle hybrids. The presentation stated the main observed threats to hawksbills are plastic and boat strikes, with ongoing studies about the impact of those threats. This project is part of the ICAPO network.

México-Pacific region. This presentation stated that in previous years the hawksbill turtle was abundant, but subsequently the population has decreased. In 2012, a hawksbill turtle was incidentally captured by longline fishing gear in an unexpected area. The turtle was rescued and rehabilitated, and prior to release it was given a satellite transmitter. This turtle suggests that there may be more hawksbill turtles in the area than originally thought.

Nests have also been found in several locations of the Mexican Pacific, and there has been constant monitoring for nesting events since 1983 in Costa Careyes and Punta de Mita. There have been assessments of the timing of nesting, and the presentation stated that some areas need better monitoring because it is possible that there is unrecorded nesting of hawkbsills in other locations. There are some foraging areas in Gulf of Cortés in Sinaloa and Jalisco states, in which they have captured juveniles and adults. They also have carried out body condition assessments, monitoring, and satellite telemetry. This project is part of the ICAPO network.

Panamá-Caribbean region. Authors presented historical data gathered between the 1950s and 1980s, when the population of hawksbill turtles was subjected to a high fishing pressure due to permitted capture carried out by ‘veladores’ to commercialize them.
In 2003, a conservation project was established in Playa Chiriqui and the Ngäbe Bugle comarca in Escudo de Veraguas and the Isla de Bastimentos Marine Park, being one of the most important nesting sites for hawksbills in the Caribbean (Meylan et al. 2013). The project collects data on morphology, maturation time, genetic identification, and migration patterns. The main threats currently are trade, depredation by pets on the beach, uncontrolled tourism, solid waste, bottom reef destruction, and sand removal for construction.

Uruguay and Argentina. The presence of hawksbill turtles in the South Atlantic is generally assumed to be restricted to areas from the equator to as far south as Brazil. However, the authors presented information on fourteen records of this species further south, in Uruguayan and Argentinean waters. They suggested that, perhaps, the recent observations are due to current effects and abnormalities in water temperatures. Both countries describe encountered hawksbill turtle as having an abundance of epibionts in the carapace and plastron, and there have been observations of plastic inside the digestive tract.

Venezuela. Historical data of hawksbill turtles in Venezuela were presented for the first time in 2002 (Buitrago & Guada 2002), with descriptions of the distribution, nesting and foraging areas of the country. In the eastern part of the country, the presenters have assessed the effect of industrial fishing on hawksbill turtles, as well as threats of bycatch and illegal trade, specifically in ‘Los Testigos’ Archipelago and Mochima National Park where they captured and tagged juvenile and adults individuals. In Tortuga Island, hawksbill aggregations are limited mainly to the south and their main threats are by-catch and possible touristic development in the future.

The authors emphasised the importance of Los Roques Archipelago as a foraging area for hawksbill turtles, where they are the most abundant marine turtle species in the area, at least in terms of juveniles. The principal threats in Los Roques are illegal trade, by-catch, and climate change. An initiative was proposed for hawksbills conservation whose primary aims are to quantify nests and identify threats. The project is slated to begin in July 2018, with the financial support of national and international institutions. The Gulf of Venezuela (GV) was reported to be one of the most important foraging areas of the country for marine turtles. Throughout the GV, aggregations of animals are in seagrass beds, rocky bottoms, and reef patches. There are also scarce but annual records of nesting in the northern area. The major threats in GV are intentional catch, illegal trade, and traditional use by the indigenous Wayuu communities. The authors also discussed the Macuro Project, in the Gulf of Paria, which has conducted conservation programs for 15 years. Currently, they conduct research and conservancy programs, to promote coastal clean-ups before the marine turtle nesting season. Their aim also is to implement an educational, outreach and training program in the area.

ICAPO. The Iniciativa Carey del Pacífico Oriental (ICAPO) is a regional initiative that covers the Eastern Pacific from the United States to Peru, and integrates other countries and territories. It started in 2007 in Mexico and then expanded to Ecuador and El Salvador. By 2008, they had a large number of institutions involved. The authors presented the initial discoveries of ICAPO, including the use of mangrove habitat by hawksbill turtles, which was largely unknown prior to this. The authors also explained the limited movement of hawksbills in the region, taking up residency in areas near to their nesting sites with a distribution in small shallow habitats.

ICAPO is a regional initiative that includes local and national projects. Currently, ICAPO is re-evaluating the current status of hawksbill turtles in the Pacific and they have discovered new nesting areas and reported a population of 700 nesting females throughout the Pacific. Despite this good news for the species, uncertainties remain about its future conservation status.

Acknowledgments. The authors express their gratitude to all RETOMALA’s attendees and presenters. Also, ISTS organizers for their support, especially Dr. Yoshi Matsusawa (ISTS President - 2018), Dr. Takashi Ishihara (ISTS Program Chair - 2018), and Dr. Takahiro Shimada. We thank Chloe Nash (University of Chicago) for her help in improving the English of this manuscript. The authors are grateful for the travel grants provided by the ISTS and all its donors.

BJORNDAL, K.A., A.B. BOLTEN & C.J. LAGUEUX. 1993. Decline of the Nesting Population of Hawksbill Turtles at Tortuguero, Costa Rica. Conservation Biology 7: 925-927.
BUITRAGO, J. & H.J. GUADA. 2002. La tortuga carey (Eretmochelys imbricata) en Venezuela. Interciencia 27: 392-399.

CAMPBELL, C.L. 2014. Conservation status of hawksbill turtles in the Wider Caribbean, Western Atlantic and Eastern Pacific regions. IAC Secretariat Pro Tempore, Virginia USA. 76p.

CARRIÓN-CORTEZ, J., C. CANALES-CERRO, R. ARAUZ & R. RIOSMENA-RODRÍGUEZ. 2013. Habitat use and diet of juvenile eastern pacific hawksbill turtles (Eretmochelys imbricata) in the North Pacific Coast of Costa Rica. Chelonian Conservation & Biology 12: 235-245.

DUNBAR, S., H. ITO, K. BAHJRI, S. DEHOM & L. SALINAS. 2014. Recognition of juvenile hawksbills Eretmochelys imbricata through face scale digitization and automated searching. Endangered Species Research 26: 137-146.

LILES, M.J., M.J. PETERSON, J.A. SEMINOFF, E. ALTAMIRANO, A.V. HENRÍQUEZ, A.R. GAOS, V. GADEA, J. URTEAGA, P. TORRES, B.P. WALLACE & T.R. PETERSON. 2015. One size does not fit all: Importance of adjusting conservation practices for endangered hawksbill turtles to address local nesting habitat needs in the eastern Pacific Ocean. Biological Conservation 184: 405-413.

MARCOVALDI, M. A., G. G. LOPEZ, L. S. SOARES, A. J. B. SANTOS, B. BELLINI & P. C. R. BARATA. 2007. Fifteen Years of Hawksbill Sea Turtle (Eretmochelys imbricata) Nesting in Northern Brazil. Chelonian Conservation & Biology 6: 223-228.

MARCOVALDI, M.Â., G.G. LOPEZ, L.S. SOARES & M. LÓPEZ-MENDILAHARSU. 2012. Satellite tracking of hawksbill turtles Eretmochelys imbricata nesting in northern Bahia, Brazil: turtle movements and foraging destinations. Endangered Species Research 17: 123-132.

MEYLAN, A. B. 1999. Status of the Hawksbill Turtle (Eretmochelys imbricata) in the Caribbean Region. Chelonian Conservation & Biology 3: 177-184.

MEYLAN, A. B., P. A. MEYLAN & C. ORDOÑEZ ESPINOZA. 2013. Sea turtles of Bocas del Toro Province and the Comarca Ngöbe-Buglé, Republic of Panamá. Chelonian Conservation & Biology 12: 17-33.

MORTIMER, J. A & M. DONNELLY. (IUCN SSC Marine Turtle Specialist Group). 2008. Eretmochelys imbricata. The IUCN Red List of Threatened Species 2008: e.T8005A12881238. http://dx.doi.org/10.2305/IUCN.UK.2008.RLTS.T8005A12881238.en

WALLACE, B.P., A.D. DIMATTEO, B.J. HURLEY, E.M. FINKBEINER, A.B. BOLTEN, M.Y. CHALOUPKA, B.J. HUTCHINSON, F.A. ABREU-GROBOIS, D. AMOROCHO, K.A. BJORNDAL, J. BOURJEA, B.W. BOWEN, R.B. DUEÑAS, P. CASALE, B.C. CHOUDHURY, A. COSTA, P.H. DUTTON, A. FALLABRINO, A. GIRARD, M. GIRONDOT, M. H. GODFREY, M. HAMANN, M. LÓPEZ-MENDILAHARSU, M.A., MARCOVALDI, J.A. MORTIMER, J.A. MUSICK, R. NEL, N.J. PILCHER, J.A. SEMINOFF, S. TROËNG, B. WITHERINGTON & R.B. MAST. 2010. Regional Management Units for marine turtles: a novel framework for prioritizing conservation and research across multiple scales. PloS ONE 5: e15465.