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The presence of fibropapilloma and its associated chelonid herpesvirus 5 (ChHV5) was assessed in 82 wild sea turtles. Olive ridley turtles Lepidochelys olivacea (n = 58) were caught in the pelagic Area of Marine Influence (AMI) (off the coast of Guasave, Sinaloa), and black turtles Chelonia mydas agassizii (n = 24) were captured in the Navachiste Lagoon System. The apparent physical condition was evaluated as 'good' or 'poor' by physical examination. The population structure and general health status was determined by condition index, hematocrit and total plasma protein. Detection of ChHV5 from skin samples was done by PCR. The overall physical condition of black turtles was good and all the individuals were tumor-free. Likewise, the physical condition of most olive ridley turtles was good, except for 10 individuals with poor condition. Of these, 4 had fibropapilloma-like tumors. PCR analyses showed that 3 tumors were ChHV5-positive. The DNA sequence showed 96% identity with ChHV5. All other skin samples from black or olive ridley turtles were ChHV5-negative. This is the first report of fibropapillomatosis-ChHV5 in foraging grounds off northern Sinaloa. The virus was present in a small proportion of L. olivacea individuals, a free-ranging species. It is suggested that infected turtles acquired the virus at a different location somewhere during their development before arriving in the AMI zone. This finding makes the case for setting up a health monitoring program for turtle populations in the area, enforcing sanitary measures to reduce the spread of the pathogen.

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Resumen El Golfo Dulce es uno de los pocos fiordos tropicales del mundo, y recientemente ha sido declarado como un Área Marina de Pesca Responsable (AMPR), albergando ecosistemas de manglar, corales y pastos marinos que son áreas de alimentación importantes para la tortuga verde (Chelonia mydas). En este estudio estimamos la captura por unidad de esfuerzo (CPUE) y la estructura de la población, en un sitio del sector oeste del Golfo Dulce. Entre agosto de 2010 y marzo de 2013, se capturaron un total de 253 tortugas verdes (incluyendo 20 recapturas) utilizando redes de enmalle. La CPUE anual (CPUE, 1 unidad: 100m de red por 7h) durante el estudio osciló entre 0.19 y 0.45, reduciéndose progresivamente a través de los años, posiblemente propiciado por una mortalidad masiva ocurrida en enero de 2013. Se encontró que la estacionalidad y la temporalidad influyen en la CPUE de acuerdo al modelo de mejor ajuste. Cerca del 78.17% de las tortugas capturadas fueron consideradas como adultas, con un promedio de largo curvo de caparazón (LCC) de 79.6±0.9cm. Se recapturó una hembra que había sido previamente marcada en el Archipiélago de Galápagos. Mientras que ninguna de las tortugas marcadas en el Golfo Dulce fue reportada anidando en alguna playa. Nuestros resultados sugieren que el Golfo Dulce es un área importante para la tortuga verde, en donde se congregan individuos adultos o subadultos para alimentase de los pastos marinos y las partes carnosas de los mangles. Asimismo, el área representa un gran reto para la conservación internacional, ya que posiblemente las hembras adultas que capturamos provienen de playas de anidación de Panamá y Colombia, lo que requiere de acuerdos multilaterales que propicien la recuperación de la tortuga verde del Pacífico Este. Sugerimos la continuación de este proyecto de conservación para utilizar a las tortugas marinas como especie sombrilla para la protección de los ecosistemas del Golfo Dulce.

Abstract The Golfo Dulce is one of the few tropical fjords in the world, and has recently been declared a Marine Area for Responsible Fisheries (AMPR), harboring mangrove ecosystems, coral reefs and seagrass beds, which are important feeding areas for green turtles (Chelonia mydas). In this study we estimate the catch per unit effort (CPUE) and population structure in a site in the western sector of the Golfo Dulce. Between August 2010 and March 2013, were captured a total of 253 green turtles (including 20 recaptures) using entanglement nets. The annual CPUE (CPUE, 1 unit: 100m of net for 7h) during the study ranged between 0.19 and 0.45, decreasing gradually over the years, possibly prompted by mass mortality occurred in January 2013. We found that seasonality and temporality influence the CPUE according to the best-fit model. About 78.17% were considered adult females, with an average length of curved carapace (LCC) of 79.6±0.9cm. The female recaptured has been tagged previously in the Galapagos Archipelago. While none of the turtles tagged in the Golfo Dulce was reported nesting on any other beach. Our results suggest that the Golfo Dulce is an important area for green turtles, where individuals congregate for adults and subadults would feed on seagrasses and the fleshy parts of the mangroves. The area also represents a major challenge for international conservation, possibly because we captured adult females from nesting beaches of Panama and Colombia, which requires multilateral agreements that promote the recovery of the East Pacific green turtle. We suggest the continuation of this conservation project to use sea turtles as umbrella species to protect ecosystems in the Golfo Dulce. Rev. Biol. Trop. 63 (Suppl. 1): 363-373. Epub 2015 April 01.

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We analyzed mtDNA control region sequences of green turtles (Chelonia mydas) from Arvoredo Island, a foraging ground in southern Brazil, and identified eight haplotypes. Of these, CM-A8 (64%) and CM-A5 (22%) were dominant, the remainder presenting low frequencies (< 5%). Haplotype (h) and nucleotide (π) diversities were 0.5570 ± 0.0697 and 0.0021 ± 0.0016, respectively. Exact tests of differentiation and AMOVA Φ(ST) pairwise values between the study area and eight other Atlantic foraging grounds revealed significant differences in most areas, except Ubatuba and Rocas/Noronha, in Brazil (p > 0.05). Mixed Stock Analysis, incorporating eleven Atlantic and one Mediterranean rookery as possible sources of individuals, indicated Ascension and Aves islands as the main contributing stocks to the Arvoredo aggregation (68.01% and 22.96%, respectively). These results demonstrate the extensive relationships between Arvoredo Island and other Atlantic foraging and breeding areas. Such an understanding provides a framework for establishing adequate management and conservation strategies for this endangered species.

RESUMO

We analyzed mtDNA control region sequences of green turtles (Chelonia mydas) from Arvoredo Island, a foraging ground in southern Brazil, and identified eight haplotypes. Of these, CM-A8 (64 percent) and CM-A5 (22 percent) were dominant, the remainder presenting low frequencies (< 5 percent). Haplotype (h) and nucleotide (n) diversities were 0.5570 ± 0.0697 and 0.0021 ± 0.0016, respectively. Exact tests of differentiation and AMOVA Fi ST pairwise values between the study area and eight other Atlantic foraging grounds revealed significant differences in most areas, except Ubatuba and Rocas/Noronha, in Brazil (p > 0.05). Mixed Stock Analysis, incorporating eleven Atlantic and one Mediterranean rookery as possible sources of individuals, indicated Ascension and Aves islands as the main contributing stocks to the Arvoredo aggregation (68.01 percent and 22.96 percent, respectively). These results demonstrate the extensive relationships between Arvoredo Island and other Atlantic foraging and breeding areas. Such an understanding provides a framework for establishing adequate management and conservation strategies for this endangered species.

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