Tras la pista de especies con ciclos de vida complejos: lecciones de la tortuga boba del Mediterráneo (Caretta caretta)

9 Març 2018
Sala d'Actes
Impartida per: 
Dr. Carlos Carreras
Departament de Genètica i Institut de Recerca de la Biodiversitat, Universitat de Barcelona


Marine turtles are characterised by having complex life cycles that takes decades to complete. These cycles usually include migrations that involve very distant geographical areas, both at nesting beaches and at sea. Furthermore, marine turtles spent most of their lives at sea, and thus are difficult to study during long periods. The Mediterranean loggerhead turtle (Caretta caretta) provides an excellent case study on how highly migratory species with complex life cycles can be studied. The combination of genetics with additional techniques has allowed the answering of many different biological and conservation questions in the past decades on these endangered animals. This includes population structuring, determined by female and male philopatry, or how the Mediterranean was colonised and survived past cold events. Furthermore, genetics have provided unique tools for identification of the population of origin of animals at sea, allowing the assessment of the impact of fisheries related mortality to the populations affected, to detect barriers to dispersion, to establish foraging strategies and to determine differential growth rates related to the origin of the individuals. Finally, sporadic nesting events in the western Mediterranean have been associated to colonisation events as an effect of global warming and as a potential mechanism to exploit new suitable nesting habitats despite philopatry. All these results show the potential of genetics to study highly migratory species.


Brief biography

Deciphering the structuring and connectivity of marine organisms is crucial to understand their biology and to develop conservation and management plans by establishing links between threats and affected populations. Carlos Carreras has devoted his career to study the biology, population genetics, distribution, migration, conservation and adaptation of marine organisms. During his PhD at the University of Barcelona, followed by a PhD-student stay at the Biological Station of Doñana-CSIC, he investigated the connectivity of the different loggerhead sea turtle populations at different stages (juveniles and adults) in the Mediterranean and the Atlantic and linked these populations with the different fisheries threats found in the area. This was accomplished by combining the use of genetic markers with several additional techniques, including satellite telemetry, aerial surveys, particle modelling, experimentation with captive animals or fisheries interaction evaluation. During his postdoctoral stay he continued his research on different species of marine turtles but he also started his interest on the impact of climate change on marine species and the mechanisms of these species to react. Thus, highly philopatric species with temperature determined sex could colonise new areas when the previously reproductive beaches become unsustainable using long dispersal mechanisms. He continued the study of adaptation to temperature changes and connectivity of populations when he moved to the University of Barcelona by using high throughput sequencing to detect and genotype SNPs on a variety of marine organisms.