Étude de l’incidence des blessures externes chez les cétacés des Petites Antilles, et caractérisation préliminaire des pressions anthropiques associées
Fecha
2023-08-28
Tipo
propuesta de investigación
Autores
Gauducheau, Victor
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Editor
Resumen
Of the 93 known species of cetaceans, one-third are found in the Caribbean. Yet there are few large-
scale scientific studies of them in this region. Besides, with 70% of the local population directly
dependent on the sea (fishing, tourism) and numerous shipping lanes, cetaceans are particularly
exposed to human pressures. Thanks to two years of sea expeditions and a substantial sampling
effort in the Lesser Antilles, over 5,200 cetacean photographs have been collected and analyzed.
The creation of a key for determining the anthropogenic or natural origin of the cetaceans’ injuries
has enabled a preliminary estimate of the quantification and location of anthropogenic pressures
linked to maritime traffic and fishing activities in the Lesser Antilles. Cetacean species present
distinct injury profiles, with some being more marked than others by anthropogenic injuries,
especially the dwarf and pygmy sperm whales (Kogia sp.) and the pygmy killer whale (Feresa
attenuata), though they would require more observations. This is also the case for the melon-
headed whale (Peponocephala electra), for which the level of confidence is more reasonable. In
contrast, the most frequently observed species, the pantropical spotted dolphin (Stenella
attenuata), is very little marked. This species can nevertheless be used as a basis for a spatial
analysis of injury distribution, thanks to its resident nature on each island. However, it cannot really
act as a sentinel species, as only 9% of individuals bear anthropogenic wounds. Nevertheless, the
spatial distribution of wounds observed (fresh wounds and on S. attenuata, a resident species)
seems to indicate that certain areas, such as Saint Vincent and the Grenadines, Saint Lucia or the
French islands of Martinique and Guadeloupe, are particularly associated with high anthropogenic
impacts. Finally, certain biological and ethological characteristics, such as black color, low age of
sexual maturity and high maximum dive duration, seem to increase the susceptibility of being
injured by human activities. This is confirmed by a Random Forest artificial intelligence model, but
more balanced data across species would give greater confidence in these results. More
information on the distribution and behavior of species in the Lesser Antilles, together with
international cooperation, would lead to a better understanding of the threats to cetaceans, and to
more effective global conservation measures.
Descripción
Propuesta de TFG de maestría con doble titulación coordinada con la Maestría Académica en Gestión Integrada de Áreas Costeras Tropicales.
Palabras clave
cetáceos, foto-identificación, analisis de herridas, perturbación antrópica, trafico maritimo