Data/hora: 16/06/2024 03:14:45

Provedor de dados: | 5
País: | France
Título: | STAMM : un modèle individu-centré de la dispersion active des tortues marines juvéniles. Applications aux cas des tortues luths du Pacifique Ouest et de l’Atlantique Nord-Ouest et aux tortues caouannes de l’ouest de l’océan Indien.
Autores: | Lalire, Maxime.
Data: | 2017-06-26
Ano: | 2017
Palavras-chave: | Courants marins; Dispersion; Ecologie spatiale; Modélisation lagrangienne; Modèles de mouvement; Modèles d'habitat; Simulations numériques; Tortues marines juvéniles; Tortue luth; Tortue caouanne; Oceanic currents; Dispersal; Spatial ecology; Lagrangian modelling; Movement modelling; Habitat modelling; Numerical simulations; Juvenile sea turtles; Leatherback turtle; Loggerhead turtle.
Resumo: | Sea turtles are increasingly threatened by the direct and indirect effects of human activities. Their life cycle is complex, shared between various, and often very distant, habitats. Their conservation therefore requires identifying the habitats occupied at each stage of life and the migration routes between these different habitats. While the spatial ecology of adult turtles is relatively well known, particularly through satellite monitoring, the situation is not the same for juveniles which pelagic development phase remains largely unobserved. In that context, numerical simulation constitutes an appropriate tool to explore the dispersal of juvenile sea turtles from their natal beaches. Until now, simulations were mostly performed under the assumption that juveniles disperse passively with oceanic currents. In this PhD thesis we present STAMM (Sea Turtle Active Movement Model), a new model of active dispersal that aims to go beyond the initial hypothesis of passive drift. In STAMM, juvenile sea turtles move under the influence of ocean currents and swimming movements motivated by the search for favorable habitats. This model is applied here to the study of the dispersal of juveniles from three sea turtle populations: leatherback turtles (Dermochelys coriacea) of the Western Pacific and the Northwest Atlantic Oceans, and loggerhead turtles (Caretta caretta) of the Western Indian Ocean. Our results show that, although ocean currents broadly shape juvenile dispersal areas, simulations including habitat-driven movements provide more realistic results than passive drift simulations. Habitat-driven movements prove to deeply structure the spatial and temporal distribution of juveniles. In particular, they induce seasonal latitudinal migrations that reduce cold induce mortality. They also push simulated individuals to concentrate in productive areas that cannot be accessed through pure passive drift. These results challenge the classical view of juveniles circulating passively around oceanic gyres. They should rapidly be taken into account for the implementation of targeted conservation measures concerning juvenile sea turtles.
Tipo: | Text
Idioma: | Francês

Identificador:

https://archimer.ifremer.fr/doc/00497/60912/64263.pdf

https://archimer.ifremer.fr/doc/00497/60912/

Editor: | Université de Toulouse
Formato: | application/pdf

Fonte:

info:eu-repo/semantics/openAccess

restricted use