Phenotypically linked dichotomy in sea turtle foraging requires multiple conservation approaches

[EN] Marine turtles undergo dramatic ontogenic changes in body size and behavior, with the loggerhead sea turtle, Caretta caretta, typically switching from an initial oceanic juvenile stage to one in the neritic, where maturation is reached and breeding migrations are subsequently undertaken every 2-3 years [1-3]. Using satellite tracking, we investigated the migratory movements of adult females from one of the world's largest nesting aggregations at Cape Verde, West Africa. In direct contrast with the accepted life-history model for this species [4], results reveal two distinct adult foraging strategies that appear to be linked to body size. The larger turtles (n = 3) foraged in coastal waters, whereas smaller individuals (n = 7) foraged oceanically.

Potential adverse health effects of persistent organic pollutants on sea turtles: Evidences from a cross-sectional study on Cape Verde loggerhead sea turtles

[EN] The Cape Verde nesting population of loggerhead sea turtles (Caretta caretta) is the third largest population of this species in the world. For conservation purposes, it is essential to determine how these reptiles respond to different types of anthropogenic contaminants. We evaluated the presence of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in the plasma of adult nesting loggerheads from Boa Vista Island, Cape Verde, and studied the effects of the contaminants on the health status of the turtles using hematological and biochemical parameters. All turtles had detectable levels of non-dioxin like PCBs, whereas dioxin-like congeners (DL-PCBs) were detected in only 30% of the turtles.

Satellite tracking derived insights into migration and foraging strategies of male loggerhead turtles in the eastern Atlantic

[EN] In recent years, information about the movements and timing of migration by male sea turtles has begun to be unraveled. Here, we present the first satellite tracking of male loggerhead sea turtles (Caretta caretta) in the eastern Atlantic. Satellite linked transmitters were attached to five adult males, captured in the near shore waters off Boavista, Republic of Cape Verde. This archipelago hosts the single most important breeding site of loggerhead turtles in the eastern Atlantic.

The international importance of the archipelago of Cape Verde for marine turtles, in particular the loggerhead turtle Caretta caretta

[ES] The shores of Cape Verde hosts one of the most important nesting populations of the loggerhead turtle Caretta caretta in the world, as well as important feeding grounds for hawksbill Eretmochelys imbricata and green turtles Chelonia mydas. In the past few years, a number of scientific studies have demonstrated the relevance of the waters and beaches of this archipelago for the conservation of these endangered marine megavertebrates. This article aims to bring together the most relevant scientific information published on the subject so far. In addition, we will provide an overview of the current situation of sea turtles in Cape Verde, their conservation status and their importance in an international context.

New records of the olive ridley sea turtle Lepidochelys olivacea (Eschscholtz, 1829) from the Cape Verde Islands

[ES] The olive ridley sea turtle Lepidochelys olivacea has been recorded in the Cape Verde Islands, but the most recent published data (1998-2000) are of stranded ndividuals and remains only. This article presents new data on olive ridleys recorded during the years 2001-2011 on Boavista and Sal islands. The presence of his species does not appear to be related to nesting activity. The possible geographical origin of these turtles is discussed. In addition, we propose some studies that could help to reinforce the conservation of sea turtles in West Africa.

First records of Fraser's dolphin Lagenodelphis hosei for the Cape Verde Islands

[ES] On 31 August 2003, at 11:40 local time, c. 5 nm southwest of São Nicolau 16º33.1N, 024º27.7W), Cape Verde Islands, GT and PLS observed c.20 Fraser’s Dolphins Lagenodelphis hosei Fraser, 1956 (Fig.1). The sighting was made under excellent weather conditions (sea state Beaufort 2 with sun) from the 39.6 m diesel engine powered oceanographic research vessel Taliarte during a two week cetacean survey conducted as part of the Hydrocarpo project. The animals were c. 2.5 m in length, with a short beak, robust ody, small dorsal and pectoral fins and showed the characteristic longitudinal striping (cf. efferson et al.1993, Carwardine 1995).

Manual for the monitoring of sea turtles in the Cape Verde Islands

[ES] To actively protect sea turtles on their nesting beaches, it is essential to obtain knowledge about trends in abundance. The way sea turtles live makes it extremely difficult to identify how many individuals there are in a population at any point in time. Due to practical problems, given their entirely marine life with limited visibility and great oceanic dispersal, counting males or juveniles is currently quite difficult and imprecise. Counting females and nests on beaches during the nesting season is the best feasible but still imperfect method, since only an unknown portion of adult females nest every season. It is impossible to know the real number of females in the population by merely counting females and nests in a given year.

As tartarugas marinhas da Macaronésia

[PT] As tartarugas marinhas sao anima is com um ciclo de vida complexo, caracterizado pela exploração de diferentes habitats de alimentação ao longo do seu desenvolvimento. Estas espécies efectuam extensas migrações entre as áreas de alimentação e as praias de postura, mostrando a sua incrível capacidade de orientação.

Incidental Capture of Loggerhead Turtles (Caretta caretta) on Boa Vista (Cape Verde Islands)

[EN] The sea is one of the major natural resources of the Cape Verde Islands, a small archipelago located 500 kilometers off the coast of Senegal (West Africa). This country consists of ten main islands and several islets, and possesses an Exclusive Economical Zone (EEZ) of about 734 square kilometers and a coastal perimeter of nearly 2000 kilometers. The marine shelf, whose limit is the 200 m isobath, is particularly extensive on the island of Boa Vista (Figure 1). lt is likely that most of the loggerhead turtles (Caretta caretta) that breed in this archipelago are concentrated on this island (López-Jurado et al., 1999).

Selección del gradiente térmico por ejemplares juveniles de Caretta caretta visualizado mediante técnicas de seguimiento por satélite.

[ES] Se presenta una aplicación que utiliza información de varios sensores satelitales a diferentes escalas para hacer el seguimiento de la evolución espacio-temporal de 8 ejemplares juveniles de tortuga boba (Caretta caretta) que fueron equipados con trasmisores ARGOS en las Islas Canarias entre 1999 y 2000. Consiste en una base de datos multisensor y multiescala que se fusiona con los datos de posicionamiento y buceos para producir conjuntos multiparamétricos que pueden analizarse desde el punto de vista ecofisiológico. Del uso de la aplicación se infiere información interesante sobre el comportamiento migratorio de estos reptiles en la región macaronésica.

Biodiversidad química del litoral canario

Programa de doctorado de Oceanografía, Bienio 2003-2005. La fecha de publicación es la fecha de lectura

Movement patterns and habitat use of the silver tip shark ("Carcharhinus albimarginatus") at the Revillagigedo Archipelago

[EN]The Revillegigedo Archipelago Biosphere Reserve is home to several shark species that spend at least part of their life history associated with oceanic islands associated with hotspots of pelagic biodiversity and in particular with apex predators. Silvertip sharks (Carcharhinus albimarginatus) are is commonly found in all the islands of the archipelago. However, very little is known about the spatial and temporal scales of their habitat use and associated ecological role. In this study, we employed passive acoustic telemetry to investigate the residency patterns and migration dynamics of 35 silvertip sharks tagged in three islands of the archipelago (San Benedicto, Socorro and Roca Partida) and monitored for a period of between 7 and 1165 (mean ± SD: 553.7± 354.2) days.

Analysis of cohesion calls in "Orcinus orca" (Linnaeus, 1758)

[EN]The killer whales emit emit vocal signals to maintain group cohesion. It is assumed discrete calls are used as cohesion calls, nevertheless has not been tested if any of them could be used for other reason. Combining different stereotyped discretes calls into specific sequences increases the probability to happen a call with response. The acoustic activity of five orcas (Orcinus orca) was monitored during five different nights and distributed in three pools, leaving one orca in pool A and the rest of the group between pools B and C. Out of 4311 classified vocalizations were obtained 632 call-response sequences between different pools.

Cetáceos en Canarias

[ES]El motivo de esta charla informativa es para quienes estén interesados en conocer los cetáceos que residen en Canarias; una iniciación al conocimiento de estas especies de mamíferos marinos, de saber cómo viven, cómo se trabaja en la toma de datos, cómo debemos protegerlos y cuidarlos para su supervivencia, ya que hay una gran variedad que transitan por nuestras costas