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Con el objetivo de determinar los principales parámetros poblacionales de la tortuga verde del Pacifico este (Chelonia mydasagassizii) el Instituto del Mar del Perú (IMARPE), mediante el Laboratorio Costero de Pisco, a partir del 2010 empezó las investigaciones biológicas en tortugas marinas, a través de monitoreos acuáticos en la ensenada de la Aguada, en Bahía Paracas, Pisco. Durante el periodo 2010- 2017 se determinó el largo curvo del caparazón (LCC), presentando promedio de 58,4 ± 7,9 cm (rango: 40,9 - 84,5 cm, n=438) con 88,7% de juveniles y 11,3% de sub-adultos. Estas tallas son las menores registradas en el Pacifico este para la especie. El número promedio de tortugas capturadas por km de red tendida por hora fue 1,03 ±1,23 (rango: 0 - 5,9, n=83). Los principales epibiontes capturados fueron de origen costero - nerítico: Platylepas hexastylos (40,5%, n=570), Stephanolepas muricata (13,4%, n=189), Conchoderma virgatum (13,1%, n=184), Ozobranchus margoi (12,9%, n=181), Chelonibia testudinaria (10,3%, n=145), y también de origen pelágico – oceánico: Lepas anatifera (8,5%, n=120), Planes cyaneus(0,8%, n=11) y Remora remora (0,6%, n=7). Se evidencia la gran importancia de Paracas como una exclusiva zona de reclutamiento desde zonas oceánicas. Durante lo que va del proyecto (2010 – 2017) se realizaron 46 recapturas, de las cuales 41 fueron juveniles y 5 sub-adultos, también se reportaron 5 triples recapturas (todos juveniles). La residencia en el área, expresada en el número promedio de días utilizados por la especie en el área de alimentación fue de 306,2 ± 166,9 días (rango: 170 - 708, n=26), la tasa de crecimiento fue de 7,4 ± 2,8 cm/año (rango: 2,0 – 11,7, n=26), ambos análisis se realizaron considerando recapturas mayores a 170 días. El índice de condición corporal (BCI) promedio por año y por estadio fue mayor en juveniles (1,49) con respecto a los sub-adultos (1,43). La mayoría de los parámetros poblacionales fueron favorables, lasaltas tasas de crecimiento y de BCI en conjunto con las bajas tasas de recapturas demuestran que esta es una población grande, saludable y con posibles bajos niveles de endogamia. Paradójicamente es preocupante que aun subsistan capturas incidentales y dirigidas en la zona, por lo que son necesarias y urgentes las medidas de conservación y fiscalización en la zona de Pisco - Paracas.

Human activities have put the ocean under unprecedented pressure. Nevertheless, levels of public awareness of ocean issues remain low. Ocean literacy is a global movement that aims to improve the understanding of the ocean and provide an incentive for positive change in people's behaviour. To date, there is no validated scale targeted to adults to measure ocean literacy that includes measuring people's knowledge about the ocean, as well as surveying their attitudes and willingness to act. The Blue Survey, an on -line instrument meant to measure ocean literacy in adult populations, was developed by a multidisciplinary team of experts. Using factor analysis, the present study explores the validity and internal consistency of the Blue Survey in a purposive online sample of 251 adults. We found ocean literacy to consist of six sub-dimensions captured by 34 survey items, viz. knowledge of ocean-related topics, personal interest in ocean-related aspects, ocean stewardship, ocean as an economic resource, ocean-friendly behaviour, and willingness to act responsibly towards the ocean. Our analysis resulted in the development of a new validated instrument to measure the various dimensions of ocean literacy. These results may help researchers and practitioners to better understand the factors which contribute to shaping an ocean-literate person. Further research should be carried out to assess the validity of the Blue Survey across different populations, including those closely related to the sea, such as maritime professionals.

Se estudiaron los hábitos alimentarios de la tortuga verde del Pacifico Este Chelonia mydas agassizii (Boucort, 1868) durante el periodo 2013 - 2018 en el estuario de Virrilá, Sechura. Se practicó la técnica de lavado esofágico a 119 ejemplares vivos. La mayoría de los ejemplares analizados fueron sub – adultos (61,9%), seguidos por juveniles (29,2%) y adultos (8,8%). Las tortugas presentaron hábitos omnívoros, pero con alta predominancia de consumo de materia vegetal. Se identificaron 47 ítems alimentarios, agrupados en nueve Phylum, siendo las algas verdes Ulva sp. y Caulerpa filiformis los ítems principales con (Ai = 18%; Ip = 57%) y (Ai = 11%; Ip = 22%), respectivamente. Seguido de pasto marino Ruppia maritima (Ai = 11%; Ip = 13%), restos de cnidarios como anémonas Actinia sp. (Ai = 4%; Ip = 0,3%). Existió marcada estacionalidad en el consumo de presas, en verano – otoño se consumió C. filiformis (Ip = 78,4%), en invierno - primavera Ulva sp.(Ip = 52,3%) y R. maritima (Ip = 39,9%). También se encontró fragmentos de plástico (24%). El estuario de Virrilá representa una importante área de alimentación para tortugas verdes en etapas medias de desarrollo ontogénico, con predominancia de sub-adultos, convirtiéndose en área prioritaria para la conservación de esta especie amenazada ABSTRACT: From 2013 to 2018, we studied the feeding habits of the green sea turtle Chelonia mydas agassizii (Boucort, 1868) in the Virrilá estuary, Sechura. The esophageal lavage technique was practiced on 119 live specimens. Most of the specimens analyzed were sub-adults (61.9%), followed by juveniles (29.2%), and adults (8.8%). The turtles were omnivorous but with a high predominance of vegetable matter consumption. A total of 47 food items were identified, clustered in nine phyla, with green algae Ulva sp. and Caulerpa filiformis being the main items with (Ai = 18%; Ip = 57%) and (Ai = 11%; Ip = 22%) respectively, followed by seagrass Ruppia maritima (Ai = 11%; Ip = 13%), and cnidarian remains such as anemones Actinia Sp (Ai = 4%; Ip = 0.3%). There was a noticeable seasonality in prey consumption. In summer-autumn C. filiformis (Ip = 78.4%) was consumed (Ip = 78.4%), in winter-spring, Ulva sp.(Ip = 52.3%) and R. maritima (Ip = 39.9%) were the most consumed; we also found plastic fragments (24%). The Virrilá estuary is an important feeding area for green sea turtles at mid ontogenetic stages of development, with a predominance of sub-adults, which makes it a priority area for the conservation of this endangered species.

Preliminary findings regarding black turtle (Chelonia mydas agassizii) occurrence in Lobos de Tierra Island, Northern Peru showed that 95% and 5% of turtles were juveniles and sub-adults, respectively, with an overall mean curved carapace length of 57.5 ± 7 cm (26.0–74.4 cm, n = 199). A total mean density of 180.4 turtles/km2 was found with highest densities found in bays and inlets located in the southeast. Inshore densities in shallow waters (< 1.5 m) were almost one order of magnitude greater than offshore at ∼ 1.5 km. In addition, based on structured qualitative interviews with fishermen, sea turtle capture and consumption still exists in the island, though occasional and sporadic. Jellyfish (Chrysaora plocamia) and green algae (Ulva sp.) consumption plays an important role in black turtle aggregations in the island, where densities are quite high compared to other feeding grounds elsewhere. We conclude that Lobos de Tierra constitutes an important Peruvian feeding ground, with high black tu...

In order to enhance protection and conservation strategies for endangered green turtles (Chelonia mydas), the identification of neritic habitats where this species aggregates is mandatory. Herein, we present new information about the population parameters and residence time of two neritic aggregations from 2010 to 2013; one in an upwelling dominated site (Paracas ∼14°S) and the other in an ecotone zone from upwelling to warm equatorial conditions (El Ñuro ∼4°S) in the Southeast Pacific. We predicted proportionally more adult individuals would occur in the ecotone site; whereas in the site dominated by an upwelling juvenile individuals would predominate. At El Ñuro, the population was composed by (15.3%) of juveniles, (74.9%) sub-adults, and (9.8%) adults, with an adult sex ratio of 1.16 males per female. Times of residence in the area ranged between a minimum of 121 and a maximum of 1015 days (mean 331.1 days). At Paracas the population was composed by (72%) of juveniles and (28%) sub-adults, no adults were recorded, thus supporting the development habitat hypothesis stating that throughout the neritic distribution there are sites exclusively occupied by juveniles. Residence time ranged between a minimum of 65 days and a maximum of 680 days (mean 236.1). High growth rates and body condition index values were estimated suggesting healthy individuals at both study sites. The population traits recorded at both sites suggested that conditions found in Peruvian neritic waters may contribute to the recovery of South Pacific green turtles. However, both aggregations are still at jeopardy due to pollution, bycatch and illegal catch and thus require immediate enforcing of conservation measurements.