Abstract Introduction: The Cedeño Turtle Camp has been the least researched site in the Fonseca Gulf, where Olive Ridley Turtles in Honduras have been protected since 1975. Objective: To evaluate the nesting of Olive Ridley turtles (Lepidochelys olivacea) during the closed season from 2011 to 2021 in Campamento Tortuguero Cedeño, Choluteca, Honduras. Methods: From 2011 to 2021, daily monitoring of nesting activities was conducted during the closed season from the 1st to 25th of September. Patrols were conducted between 6:00-18:00 h, and 18:00-5:00 h. The total number of nesting turtles was recorded, and their eggs were collected and transported to the hatchery, where clutch and hatchling performance were tabulated. Results: A total of 1 065 L. olivacea turtles were recorded, 95 051 eggs collected, 1 065 nests marked on three beaches that were relocated in artificial hatcheries and a successful hatching of 62 747 hatchlings. Las Doradas beach was the site with the highest number of nesting turtles, followed by Los Delgaditos and lastly Cedeño. The average nesting frequency was 96 nests. From 2011 to 2021 the nest collection effort increased by 91.6 %, from 84 to 161 nests. The number of people patrolling was associated with the number of nests detected on the beaches. Conclusion: Monitoring and conservation efforts for L. olivacea in the Campamento Tortuguero Cedeño show a positive trend in nesting with a greater increase in Playa Las Doradas. This scenario proves the functionality of the closed season in this area.

Resumen Introducción: El Campamento Tortuguero de Cedeño ha sido el sitio menos investigado del Golfo de Fonseca, donde se protege a la tortuga golfina en Honduras desde 1975. Objetivo: Evaluar la anidación de la tortuga Golfina (Lepidochelys olivacea) durante la temporada de veda entre el 2011 y 2021 en Campamento Tortuguero Cedeño, Choluteca, Honduras. Métodos: Entre 2011 a 2021, se llevó a cabo el monitoreo diario de las actividades de anidación durante la veda del 1 al 25 de septiembre. Los patrullajes se realizaron entre las 6:00-18:00 h, y las 18:00-5:00 h. Se registró el número total de tortugas que anidaban y se recogieron sus huevos, que se transportaron al criadero, donde se tabularon los resultados de las puestas y las crías. Resultados: Se registró un total 1 065 tortugas de L. olivacea, 95 051 huevos recolectados, 1 065 nidos marcados en tres playas que fueron reubicados en viveros artificiales y una eclosión exitosa de 62 747 neonatos. La playa Las Doradas fue el sitio con el mayor número de tortugas anidadoras, seguido de Los Delgaditos y por último Cedeño. El promedio de la frecuencia de anidación fue de 96 nidos. Del 2011 al 2021 el esfuerzo de recolección de los nidos aumentó en un 91.6 %, pasando de 84 a 161 nidos. El número de personas patrullando se asoció con la cantidad de nidos detectados en las playas. Conclusión: Los esfuerzos de monitoreo y conservación para la especie han indicado que ha habido un incremento en la anidación de L. olivacea en las tres playas, con un mayor incremento en Playa Las Doradas. Este escenario comprueba la funcionalidad de la veda en esta zona.

ABSTRACT Research on olive ridley sea turtle (Lepidochelys olivacea) has emphasized egg-laying females and neonates, using data collected on nesting beaches, but no systematic studies on morphological characteristics by size and sex have been published. This research describes the morphometry of free-living olive ridley sea turtles from coastal and oceanic waters of the Mexican Central Pacific captured and released from 2011 through 2013. A total of 3469 km was surveyed, and 142 sea turtles were evaluated by sex, size class, marine area, and geographic region for nine corporal measurements and their allometric relationships. The average curved carapace length (CCL) was 62.12 cm, range 42-94 cm. Significant differences were found by sex and size class with total tail length (TTL) (♂ = 26.33 cm, ♀ = 12.4 cm); similarly with vent to tail tip length (VTTL) (♂ = 6.38 cm, ♀ = 3.86 cm); and for rear flipper length (RFL) (♂ = 28.17 cm, ♀ = 38.62 cm, immatures = 23.80 cm). Turtles from the coastal region of Colima-Michoacán showed longer CCL = 62.46 cm and wider CW = 66.58 cm. Adult female RFLs showed positive allometry, b = 1.098, suggesting an accelerated growth of the posterior extremities, probably favoring reproductive behaviors, e.g. nest digging and egg-covering. Morphological differences were likely due to ontogenetic sexual distinctions rather than marine area or geographic differences.

Resumen Introducción: Para incrementar el número de crías de tortugas marinas, es necesario mejorar estrategias de conservación, como incubación de nidos, en condiciones de vivero que contrarresten los efectos de las condiciones climáticas extremas. Objetivo: Comparar cinco parámetros de éxito reproductivo (éxito de eclosión, huevos sin desarrollo aparente, crías muertas, mortalidad embrionaria y período de incubación) de la tortuga marina Lepidochelys olivacea. Métodos: Se evaluó la incubación de nidos bajo dos períodos de reubicación de nidos (P1 ~28.8 °C agosto-septiembre y P2 ~27.1 °C octubre-noviembre, temperatura ambiental promedio, bajo condiciones de vivero, en el 2018 en Guerrero, México. Resultados: Se encontraron diferencias significativas en el éxito de eclosión y la mortalidad embrionaria entre los períodos de reubicación de nidos (P < 0.001). En P1, se observaron valores más bajos de éxito de eclosión (77.0 % P1 vs 88.6 % P2) y valores más altos de mortalidad embrionaria (13.7 % P1 vs 3.3 % P2) comparados con los de P2. Es importante señalar que, en el presente estudio la mortalidad embrionaria se presentó en una etapa tardía de desarrollo, es decir, en embriones casi completamente desarrollados. No se encontraron diferencias entre periodos respecto a los parámetros de huevos sin desarrollo aparente, crías muertas y período de incubación. Conclusiones: Las diferencias entre las condiciones ambientales durante el primer período de reubicación de nidos en comparación con el segundo período parecen afectar el éxito de eclosión y mortalidad embrionaria de L. olivacea. Por lo tanto, es importante tomar medidas al respecto durante esta etapa de incubación para tratar de mejorar la incubación de nidos bajo condiciones de vivero.

Abstract Introduction: In order to increase the number of sea turtle hatchlings, it is necessary to improve conservation strategies, such as nest incubation in hatchery conditions that counteract the effects of extreme climatic conditions. Objective: To compare five reproductive success parameters (hatching success, eggs with no apparent embryonic development, dead hatchlings, embryonic mortality, and incubation period) of the sea turtle Lepidochelys olivacea. Methods: The incubation of nests was evaluated under two periods of nest relocation, P1 ~28.8 °C (August and September) and P2 ~27.1 °C (October and November), average ambient temperature, under hatchery condition, in 2018 in Guerrero, Mexico. Results: Significant differences were found in hatching success and embryonic mortality between nest relocation periods (P < 0.001). In P1, lower values of hatching success (77.0 % P1 vs 88.6 % P2) and higher values of embryonic mortality (13.7 % P1 vs 3.3 % P2) were observed compared to those of P2. It’s important pointing that, in the present study, embryonic mortality occurred at a late stage of development, that is, in almost fully developed embryos. No differences were found between periods regarding the parameters eggs with no apparent embryonic development, dead hatchlings and incubation period. Conclusions: The differences between the environmental conditions during the first period of nest relocation compared to the second period, respectively, seem to affect the hatching success and embryonic mortality of L. olivacea. Therefore, it is important to take action on this issue during this incubation stage to try to improve the incubation of nests under hatchery conditions.

Abstract At the marine turtle conservation program in Boca de Tomates, Jalisco, Mexico, all nests are relocated to fenced-off beach hatchery or polystyrene boxes due to illegal egg collection, predation, erosion, and high sand temperatures. For both methods we evaluated the following nest viability and hatchling quality parameters: hatching success, nest temperatures, incubation duration, and hatchling quality (locomotor performance, morphometrics, weight, and congenital malformations). Hatching success was significantly higher in the beach hatchery (mean 77.4%, n = 1,368) than in boxes (average 59.91%, n = 1,160) (P < 0.001). The beach hatchery nests hatched in less time (hatchery = 46 d, boxes = 51 d) (P < 0.001) due to the significantly higher mean temperature (hatchery = 32.62 ºC, boxes 30.58 ºC) (P < 0.001). The hatchery was exposed to less temperature variability per day (hatchery = 1.46 ºC, boxes = 2.69 ºC) (P < 0.001). To test hatchling quality, 10 hatchlings were randomly selected from each nest (n = 254). The weight, size, and locomotor performance (righting response and time to crawl 3 m) of these organisms were recorded. Live and dead neonates were carefully inspected for malformations (n = 2,000). No significant difference was found between incubation methods in any hatchling quality parameter (P > 0.050). The malformations at this site have low prevalence (hatchery = 1.35%, boxes = 1.89%) and low intensity index per organism (hatchery = 1.52, boxes = 1.89) compared to other studies and species. This is the first study, to our knowledge, that compares hatchling quality from 2 ex situ incubation methods in a single species (Lepidochelys olivacea), at the same location, and during the same period of time. Carrying out studies such as this one is important, since the quality of hatchlings can contribute to their ability to survive and reproduce in the future.

Resumen Dentro del programa de conservación de tortugas marinas en Boca de Tomates, Jalisco (México), todos los nidos de Lepidochelys olivacea son reubicados a corral de playa o a cajas de poliestireno debido a la recolección ilegal de huevos, la depredación, la erosión y las altas temperaturas de la arena. Con ambos métodos de incubación evaluamos los siguientes términos de viabilidad del nido y calidad de los neonatos: éxito de eclosión, temperatura del nido, duración de incubación y calidad de neonatos (desempeño locomotor, morfometría, peso y malformaciones congénitas). El éxito de eclosión fue significativamente mayor en corral (promedio = 77.4%, n = 1368) que en cajas (promedio = 59.91%, n = 1,160) (P < 0.001). Los nidos incubados en corral eclosionaron en menor tiempo que aquellos incubados en cajas (corral = 46 d, cajas = 51 d) (P < 0.001) debido a una temperatura promedio significativamente más elevada (corral = 32.62 ºC, cajas = 30.58 ºC) (P < 0.001). El corral fue expuesto a menor variabilidad de la fluctuación térmica diaria (corral = 1.46 ºC, cajas = 2.69 ºC) (P < 0.001). No encontramos diferencia significativa en ningún parámetro de calidad de los neonatos entre los métodos de incubación (P > 0.050). Determinamos que las malformaciones en L. olivacea tienen baja prevalencia (corral = 1.35%, caja = 1.89%) y bajo índice de intensidad por organismo (corral = 1.52, cajas = 1.89) en este sitio. Este es el primer estudio que conocemos que compara la calidad de neonatos de una misma especie (L. olivacea) entre estos 2 métodos de incubación ex situ en la misma ubicación y durante el mismo periodo de tiempo. Realizar estudios similares a este es importante, puesto que la calidad de los neonatos puede contribuir a su capacidad de supervivencia y reproducción.

Resumen Introducción: A pesar de que las tortugas golfinas (Lepidochelys olivacea) son las tortugas marinas más abundantes del mundo, su información cuantitativa disponible es escasa y se encuentra distribuida de manera desigual entre regiones. Existen muchos programas de manejo y conservación para esta especie, y sus evaluaciones son necesarias para identificar tendencias de anidación y poder manejar de manera efectiva los programas de conservación actuales. PROTORMAR-UAS es un programa de Investigación y Conservación de la tortuga golfina creado por la Universidad Autónoma de Sinaloa, México. El Programa cuenta con dos estaciones biológicas: Santuario de Playa Ceuta (SPC) y Playa Caimanero (PC). Objetivo: Evaluar la tendencia de anidación de la tortuga golfina en dos playas del noroeste de México y predecir las tendencias prospectivas de anidación para los próximos 30 años. Métodos: A partir de los datos de registros anuales de anidación de 40 años para SPC (1976-2016) y 30 años para PC (1986-2016), evaluamos las tendencias de anidación, el éxito de la eclosión y los problemas de depredación y saqueo de nidos de la tortuga golfina en las dos playas del noroeste de México. Posteriormente, se calcularon las estimaciones prospectivas de anidación para los próximos 30 años usando un modelo predictivo de series de tiempo. Resultados: Se identificó una correlación positiva y significativa entre el registro anual de nidos y el tiempo de estudio para ambas playas (rho = 0.850, P ≤ 0.01 para SPC; rho = 0.677 y P ≤ 0.01 para PC); así como el éxito de eclosión promedio de 65.09 para SPC y de 60.72 % para PC. El modelo predictivo de series de tiempo indicó que las anidaciones continuarán aumentando para el 2045, tres veces para SPC y seis para PC, con respecto al último año de monitoreo. Conclusiones: Hay una clara tendencia positiva de anidación de la tortuga golfina en ambos sitios, lo cual es consistente con la tendencia observada en otros estudios recientes de la región. Por lo tanto, sugerimos incluir a PC como un área de anidación legalmente protegida, la cual se ubica en los límites latitudinales de anidación de la tortuga golfina, dada la necesidad de contar con recursos disponibles para la operación del campamento ante el aumento de anidaciones y de problemas de depredación y saqueo. Porque en México operar una playa de anidación sin ningún estatus de protección implica no tener presupuesto para su manejo.

Abstract Introduction: Although olive ridley sea turtle (Lepidochelys olivacea) are the most abundant sea turtles in the world, quantitative information is scarce and unevenly distributed among regions. There are many management and conservation programs for this species, and assessments are necessary to identify nesting trends and effectively manage current conservation programs. PROTORMAR-UAS is a Research and Conservation program for the olive ridley turtle created by the Autonomous University of Sinaloa, Mexico. The program utilizes two biological stations: Santuario Playa Ceuta (SPC) and Playa Caimanero (PC). Objective: To evaluate the nesting trend of olive ridley turtles on two beaches in Northwestern Mexico and to predict prospective nesting trends for the next 30 years. Methods: Using annual nesting data collected over 40 years at SPC (1976-2016) and 30 years at PC (1986-2016), we evaluated nesting trends, hatching success, predation and poaching of olive ridley turtles on the two beaches in Northwestern Mexico. Then, prospective nesting estimates for the next 30 years were calculated predictive time series model. Results: A positive and significant correlation was identified between the number of annual nests and time for both beaches (rho = 0.850, P ≤ 0.01 for SPC; rho = 0.677, P ≤ 0.01 for PC); the average hatching success rates were 65.09 at SPC and 60.72 % at PC. The predictive time-series model indicated that the numbers of nests will continue to increase through 2045, increasing three-fold at SPC and six-fold at PC with respect to the last year of monitoring. Conclusions: There was a clear positive trend in the number of olive ridley sea turtle nests at both sites, which is consistent with trends found in other recent studies from the region. Therefore, we suggest that PC be designated a legally protected nesting area since it is located within the latitudinal limits of olive ridley nesting and given the need for resources for camp operation considering increased nesting and current problems with predation and poaching. Because in Mexico operating a nesting beach without any protection status implies not having a budget for its management.

Resumo: Este estudo permitiu o monitoramento de ninhos de tartarugas marinhas em uma região conhecida como Bacia Potiguar, que se estende da região norte do Estado do Rio Grande do Norte (5 ° 4’1,15 “S, 36 ° 4’36,41” W) até o leste do Estado do Ceará (4 ° 38’48,28 “S, 37 ° 32’52,08” W), no Brasil. Coletamos dados de janeiro de 2011 a dezembro de 2019 com o objetivo de identificar as espécies de tartarugas marinhas que desovam na bacia, analisar o padrão espaço-temporal de nidificação, as características dos ninhos, e registrar os efeitos de fatores ambientais e antrópicos. Uma equipe de campo examinou rastros de tartarugas marinhas e sinais de ninhos. As ninhadas das tartarugas foram monitoradas diariamente até que os filhotes emergissem dos ninhos. Monitoramos ninhos de tartarugas-de-pente (Eretmochelys imbricata; n = 238) e tartarugas-oliva (Lepidochelys olivacea; n = 103). A época de nidificação para E. imbricata ocorreu entre dezembro e maio e para L. olivacea de março a agosto. Tartarugas-de-pente apresentaram maior tamanho das ninhadas, tempo de incubação, número de ovos não eclodidos e número de filhotes mortos quando comparado com tartarugas-oliva; no entanto, apresentaram menor sucesso de eclosão. Precipitação entre 0 e 22 mm e umidade relativa (UR) maior que 69% aumentaram a taxa de sucesso de eclosão para E. imbricata; entretanto, chuvas acima de 11 mm e UR 64% tiveram o mesmo efeito para L. olivacea. Sinais de roubo de ovos e presença humana (por exemplo, tráfego de veículos e resíduos de plástico na praia) foram registrados e são considerados ameaças aos ninhos. Os resultados do nosso estudo de monitoramento de longo prazo na Bacia Potiguar fornecem base para a implementação de medidas de mitigação e adoção de políticas públicas em praias de desova nesta região brasileira.

Abstract: This study monitored marine turtle nests in a region known as the Potiguar Basin, which stretches from the northern region of Rio Grande do Norte State (5°4’1.15” S, 36°4’36.41” W) to eastern Ceará State (4°38’48.28” S, 37°32’52.08” W) in Brazil. We collected data from January 2011 to December 2019 to identify species of sea turtles that spawn in the basin, to analyze the nesting spatial-temporal pattern and nests characteristics, and to record effects of environmental and anthropic factors on nests. A field team examined sea turtle tracks and nests signs. Turtle clutches were monitored daily until hatchings emerged from the nests. We monitored nests of hawksbill (Eretmochelys imbricata; n = 238) and olive Ridley turtles (Lepidochelys olivacea; n = 103). The nesting season for E. imbricata occurred between December and May and for L. olivacea from March to August. Hawksbills had clutch size, incubation time, number of unhatched eggs, and dead hatchlings higher than olive Ridley turtles; nevertheless, they presented lower hatching success. Precipitation between 0 and 22 mm and relative humidity (RH) higher than 69% increased the hatching success rate for E. imbricata; however, rainfall above 11 mm and RH 64% had the same effect for L. olivacea. Signs of egg theft and human presence (e.g. vehicle traffic and plastic residues on the beach) were recorded and are considered threats to nests. The results of our long-term monitoring study in the Potiguar Basin provide basis for the implementation of mitigation measures and adoption of management policies at nesting beaches in this Brazilian region.

Abstract Sea turtles can be a place of settlement for smaller organisms called epibionts, which are harmless guests with a unique relationship. The objective of this study was to identify the diatoms that inhabit the shell of female turtles (Lepidochelys olivacea) during the nesting season 2015-2016 in Playa Ventura, Guerrero, Mexico. A total of 46 female olive ridley sea turtles were sampled from October to January, registering 20 species and 17 genus of diatoms. The genus with the highest number of species were Gomphonema (three species) and Cocconeis (two species). The results indicate that the acquisition and proliferation of diatoms are not directly related to the behavior of the turtles, but rather to each single turtle and their habits.

Resumen Las tortugas marinas pueden ser un nicho para organismos de menor tamaño denominados epibiontes o huéspedes que no causan ningún daño a sus hospederos. El objetivo de este estudio fue identificar las diatomeas que habitan sobre el caparazón de hembras de la tortuga Lepidochelys olivacea durante la temporada de desove 2015-2016 en Playa Ventura, Guerrero, México. Se muestrearon un total de 46 tortugas golfinas, registrándose 20 especies y 17 géneros de diatomeas. Los géneros con mayor número de especies fueron Gomphonema (tres especies) y Cocconeis (dos especies). Los resultados indican que la adquisición y proliferación de las diatomeas no están relacionadas directamente al comportamiento de las tortugas en general; sin embargo, la comunidad de tortugas que arriba a estas playas podría presentar hábitos similares que propicien el establecimiento de estas diatomeas.

ABSTRACT In Ecuador, one of the main hazards for threatened marine species, such as sea turtles, is small-scale fisheries bycatch. At a global scale, currently, bycatch reduction technologies (BRTs) are being tested in many coastal nations to mitigate this issue. Despite some advances in Ecuadorian efforts for wildlife protection, BRTs to reduce bycatch have yet to be assessed. The purpose of this study was to test the BRT of net illumination using violet light-emitting diodes (LEDs) as a mitigation measure to reduce sea turtle interactions in the small-scale driftnet fishery operating from the ports of Santa Rosa, Puerto Lopez and Jaramijo. A total of 146 pairs of experimental sets (control and illuminated panes) were deployed in all ports. A generalized linear mixed-effect model (GLMM) was employed to analyze the bycatch per unit of effort (BPUE) for sea turtles, and the catch per unit of effort (CPUE) for target species; for both control and illuminated panes. Thirty-two sea turtles from three species were observed captured: olive ridley Lepidochelys olivacea (n=18), green Chelonia mydas (n=13) and leatherback turtles Dermochelys coriacea (n=1). Turtle species-specific modeling showed bycatch of green turtles declined by 93% in illuminated nets compared with control, non-illuminated nets, whereas no significant difference between control and illuminated nets was observed for olive ridley turtles. The catch per unit effort of the pelagic fish species including skipjack tuna, yellowfin tuna, mahi-mahi, thresher shark and smooth hammerhead shark was not affected by net illumination. Our results represent the first evaluation of the effects of net illumination using LEDs on reducing marine turtle bycatch in Ecuadorian small-scale driftnet fisheries. Despite its relatively small sample size, these results could be used by fisheries managers to support the implementation or further testing of this BRT in gillnet fisheries along the Ecuadorian coast.

Resumen Introducción: Lepidochelys olivacea es la tortuga marina más abundante del Pacífico colombiano y las condiciones oceanográficas en el Pacífico Oriental Tropical podrían tener un efecto en su comportamiento reproductivo. Objetivo: Evaluar la relación entre los aspectos reproductivos de L. olivacea anidantes en isla Gorgona y la temperatura superficial del mar a escala local y regional. Métodos: Se estableció la información promedio mensual de los atributos asociados con las hembras anidantes, nidos, huevos y neonatos utilizando los registros del monitoreo de anidación del Parque Natural Nacional Gorgona y se correlacionaron (correlación cruzada) con la temperatura superficial del mar de la Ensenada de Panamá y las aguas de Gorgona, y con la variabilidad en la temperatura de las regiones El Niño 1+2, El Niño 3, El Niño 3.4 y El Niño 4, sus anomalías térmicas y con los índices ONI y SOI. Las correlaciones significativas se incluyeron en modelos aditivos generalizados. Resultados: Las correlaciones inversas más altas, considerando que la máxima correlación es 1 se establecieron entre las visitas a la playa, el número de hembras anidantes, el número de nidos, el tamaño de las nidadas, los días de incubación y el éxito de eclosión y la región Niño 1+2 con un rezago de 12 meses, mientras que el diámetro y el peso de los huevos, el largo y ancho del caparazón y peso de los neonatos se correlacionaron con la anomalía de Niño 4 y los índices SOI y ONI. También se encontró que existe una tendencia no lineal a disminuir el número de hembras anidantes, número de nidos, tamaño de nidadas, diámetro y el peso de los huevos con anomalías regionales positivas. Conclusiones: Los atributos de anidación de L. olivacea en Gorgona se correlacionan principalmente con las variaciones en la temperatura superficial del mar regional, siendo bajos a temperaturas altas en el año anterior a la anidación (rezago de 12 meses).

Abstract Introduction: Lepidochelys olivacea is the most abundant sea turtle in the Colombian Pacific and oceanographic conditions at the Eastern Tropical Pacific may have an effect on its reproductive behavior Objective: To assess the relationship between reproductive aspects of L. olivacea nesting at Gorgona island and sea surface temperature at local and regional scales. Methods: Monthly mean data of reproductive attributes associated with nesting females, nests, eggs and hatchlings were established using records from Gorgona’s National Natural Park nesting monitoring and were correlated (cross-correlations) with SST of Gorgona island and Panama Bight, and with the temperature variability of the El Niño 1+2, El Niño 3, El Niño 3.4 and El Niño 4 regions, their thermal anomalies, and the ONI and SOI indexes. Significant correlations were included in a Generalized Additive Model. Results: Highest inverse correlation since maximum correlation is 1 was established between visits to the beach, number of nesting females, number of nests, clutch size, incubation days and hatching success and Niño 1+2 region with a lag of 12 months, whereas egg diameter, egg weight, straight carapace length and width and weight of hatchlings were correlated with Niño 4 anomaly, SOI and ONI indexes. It was also found that there is a non-linear tendency to decrease number of nesting females, number of nests, clutch size, egg diameter and egg weight with regional positive anomalies. Conclusions: Nesting attributes of L. olivacea in Gorgona correlate mainly with variations in regional SST, being low at high sea surface temperatures the year prior to nesting (12-month lag).

Abstract The wide variation in size and content of eukaryotic genomes is mainly attributed to the accumulation of repetitive DNA sequences, like microsatellites, which are tandemly repeated DNA sequences. Sea turtles share a diploid number (2n) of 56, however recent molecular cytogenetic data have shown that karyotype conservatism is not a rule in the group. In this study, the heterochromatin distribution and the chromosomal location of microsatellites (CA)n, (GA)n, (CAG)n, (GATA)n, (GAA)n, (CGC)n and (GACA)n in Chelonia mydas, Caretta caretta, Eretmochelys imbricata and Lepidochelys olivacea were comparatively investigated. The obtained data showed that just the (CA)n, (GA)n, (CAG)n and (GATA)n microsatellites were located on sea turtle chromosomes, preferentially in heterochromatic regions of the microchromosomes (mc). Variations in the location of heterochromatin and microsatellites sites, especially in some pericentromeric regions of macrochromosomes, corroborate to proposal of centromere repositioning occurrence in Cheloniidae species. Furthermore, the results obtained with the location of microsatellites corroborate with the temperature sex determination mechanism proposal and the absence of heteromorphic sex chromosomes in sea turtles. The findings are useful for understanding part of the karyotypic diversification observed in sea turtles, especially those that explain the diversification of Carettini from Chelonini species.

Abstract Marine turtle hybridization is usually sporadic and involves reports of only a few individuals; however, Brazilian populations have high hybridization rates. Here we investigated the presence of hybrids in morphologically identified immature hawksbills (Eretmochelys imbricata) along the South Western Atlantic (SWA). We sequenced one mitochondrial (D-Loop) and three nuclear DNA (RAG1, RAG2, and CMOS) markers to better understand the patterns and characteristics of hybrids. We identified 22 hybrids (n = 270), 11 of them at the extreme South of the SWA. Uruguay had the highest hybrid frequency in the SWA (~37.5%) followed by southern Brazil with 30%. These are common areas for loggerheads (Caretta caretta) but uncommon for hawksbills, and these hybrids may be adopting the behavior of loggerheads. By analyzing nuclear markers, we can infer that 50% of the sampled hybrids are first generation (F1) and 36% are the result of backcrosses between hybrids and pure E. imbricata (> F1). We also report for the first time immature E. imbricata x Lepidochelys olivacea hybrids at the Brazilian coast. Considering the high frequency of hybrids in the SWA, continuous monitoring should be performed to assess the fitness, genetic integrity, and extent of changes in the gene pools of involved populations.

ABSTRACT The nesting frequency and hatching percentage in artificial olive ridley sea turtle (Lepidochelys olivacea; Testudines: Cheloniidae) nests collected on different beaches (Cerritos, Zona Dorada, Malecón, Pinitos, Olas Altas) in the bay of Mazatlán, Mexico was determined. Polyurethane boxes were used for artificial nest incubation. An average hatching of 75.2% (± 19.3) was obtained. To prevent egg predation, it is important to maintain artificial incubation in polyurethane boxes. Due to the higher incidence of nests on Malecón (75.5 ± 12.4 beach nests per year) and Cerritos (51.3 ± 26.5 beach nests per year) beaches, with 11.5 and 8.3 nests km-1, respectively, it is necessary to increase their surveillance.

RESUMEN Se determinó la frecuencia de anidación y el porcentaje de eclosión en nidos artificiales de tortuga golfina (Lepidochelys olivacea) colectados en diferentes playas (Cerritos, Zona Dorada, Malecón, Pinitos, Olas Altas) de la bahía de Mazatlán, México. Se utilizaron cajas de poliuretano para la incubación artificial de nidos. Se obtuvo una eclosión promedio de crías del 75.2% (± 19.3). Para evitar la depredación de huevos es importante mantener la incubación artificial en cajas de poliuretano. Por la mayor incidencia de nidos en las playas Malecón (75.5 ± 12.4 nidos playa año) y Cerritos (51.3 ± 26.5 nidos playa año), y por 11.5 y 8.3 nidos km-1, respectivamente, es necesario incrementar su vigilancia.

RESUMEN Esta investigación se realizó en el municipio de Bahía Solano, Colombia y tuvo como objetivos: 1) detectar la circulación de eritrocitos con lesiones nucleares en 55 hembras adultas de tortuga golfina (Lepidochelys olivácea), empleando la inmunotinción de naranja de acridina y 2) correlacionar sus frecuencias con aspectos biométricos y fisiológicos. Se determinó una frecuencia de eritrocitos con micronúcleos (EMN) de 0,6 ± 0,6 y de protuberancias nucleares (EPN) de 2,1 ± 1,9. Mediante un análisis multivariado a través de la correlación de Pearson y de Kruskal-Wallis (p<0,05), no se encontró ninguna correlación positiva entre el nivel de frecuencia de EPN ni de EMN con los parámetros biométricos y fisiológicos evaluados. Se estableció una diferencia estadísticamente significativa (p= 0,035) entre las frecuencias de EPN y de EMN. Los resultados hallados indican que esta especie presenta eritrocitos circulantes con los daños nucleares mencionados y reporta por primera vez la presencia de estrés genotóxico para la especie en Colombia. Así mismo, brinda información clave para investigaciones posteriores en el área de la ecotoxicología de especies marinas amenazadas.

ABSTRACT This research was conducted in the municipality of Bahia Solano, Colombia, and had as a goal to detect damage erythrocytes circulating with nuclear lesions in fifty-five Olive Ridley adult females using acridine orange immunostain, and correlate its frequencies with some physiological and biometric parameters. We determine a micronucleated erythrocytes (MNE) frequency of 0.6 ± 0.6 and nuclear buds (NBE) of 2.1 ± 1.9. We not found any relationship between the nuclear lesions with physiological or biometric parameters evaluated (Pearson and Kruskal-Wallis, p<0.05). We define a significative statistical difference (p=0.035) between both nuclear lesions frequencies. This results show nuclear damages in erythrocytes of Olive Ridley sea turtle for the first time in Colombia as an outcome of genotoxic stress. Also contributes key information for future research in the ecotoxicology area for endangered marine species.

Abstract Background: Sea turtles of the genus Lepidochelys exhibit a complex and synchronous mass-nesting behavior termed “arribada.” Goals: This paper analyzes the local physical environment during the arribada events that occurred in 2005 at La Escobilla, Oaxaca, Mexico. Methods: Daily night patrols were conducted from May to November 2005, along the nes ting zone. Daily records for air temperature and rainfall were obtained from the automatic weather station by the Comisión Nacional del Agua. Sea surface temperature and salinity fields were obtained from the Hybrid Coordinate Ocean Model (HYCOM), and surface ocean currents were obtained from the Asia-Pacific Data Research Center. Results: The analyses showed five arribada events during the period. A common feature was the presence of eddies and strong currents at the beginning of each arribada. A correlation of statistical significance was observed between the abundance of the arribada and the current speed (R = 0.93, R2 = 0.86, p = 0.04). The correlation with salinity showed values of R = 0.55, R2 = 0.31, p = 0.32, whereas correlation with rainfall was R = 0.53, R2 = 0.28, p = 0.14. A weak correlation was observed with air temperature (R = 0.35, R2 = 0.12, p = 0.59) and with sea surface temperature (R = 0.23, R2 = 0.05, p = 0.66). Conclusions: Although sea turtles are strong swimmers, the proximity to favorable oceanic currents generated by eddies might be related to the beginning of the arribada, considering that this current might provide energy savings and accumulate chemical compounds and food in the water column.

Resumen Antecedentes: Las tortugas marinas del género Lepidochelys presentan un complejo comportamiento de anidamiento masivo conocido como arribada. Objetivos: El presente trabajo analiza la relación entre el ambiente físico durante los eventos de arribada ocurridos en 2005 en La Escobilla, Oaxaca, México. Métodos: Se realizaron patrullajes nocturnos de mayo a noviembre de 2005 y se obtuvieron registros de temperatura del aire y precipitación del radar meteorológico de CONAGUA. Mapas de salinidad y temperatura superficial del mar fueron obtenidos a partir del modelo HYCOM. Las corrientes superficiales fueron determinadas a partir de bases de datos disponibles por Centros de Investigación en dinámica oceanográfica internacionales. Resultados: Se observaron cinco eventos de arribada. Una característica im portante fue la presencia de vórtices y corrientes intensas durante su inicio. Se observó una correlación estadísticamente significativa entre las arribadas y la velocidad de las corrientes (R = 0.93, R2 = 0.86, p = 0.04). La correlación con la salinidad mostró valores de R = 0.55, R2 = 0.31, p = 0.32, mientras que la correlación con la precipitación fue R = 0.53, R2 = 0.28, p = 0.14. Se observó una correlación débil con la temperatura del aire (R = 0.35, R2 = 0.12, p = 0.59) y con la temperatura superficie del mar (R = 0.23, R2 = 0.05, p = 0.66). Conclusiones: A pesar de que las tortugas marinas son fuertes nadadoras, la proximidad a corrientes favorables generadas por los vórtices podría estar relacionada con el inicio de la arribada, considerando que estas corrientes asegurarían un ahorro en energía y su presencia podría acumular compuestos químicos y comida en la columna de agua.

Gillnets are recognized globally as one of the fishing gears with the highest levels of bycatch and mortality of sea turtles. Through onboard observer monitoring from July 2013 to June 2014 we assessed the bycatch of sea turtles by an artisanal gillnet fishery operating from Sechura Bay, Peru. One hundred and four sea turtles were incidentally caught in 53 observed fishing sets. The observed species composition of bycatch was green turtle Chelonia mydas (n = 100), hawksbill Eretmochelys imbricata (n = 3) and olive ridley Lepidochelys olivacea (n = 1). Bycatch occurred in 62.3% of monitored sets, with an average of 1.96 turtles caught per set. For all sea turtles combined, 28.8% of individuals were dead and 71.2% were alive at the time of retrieval. The majority of individuals caught were classified as juveniles and sub-adults, with an average carapace length (CCL) of 57.3 ± 0.9 cm for green turtles and 40.2 ± 2.4 cm for hawksbills. The mean annual catch per unit effort (CPUE) of sea turtles was 1.11 ± 0.31 turtles km-1 12 h-1), but varied by seasons. These results suggest that Sechura Bay is an important developmental habitat for juvenile and sub-adult green turtles and hawksbill turtles, but one subject to intense fishing interaction pressure. The development of monitoring programs, local awareness-raising activities, and enhanced management and protection of this critical foraging area and developmental habitat is recommended.