WHAT IS PERSONALITY?
Personality describes the fact that within a population, individuals consistently differ in their behaviour. While personality research was first applied to humans, a wide variety of studies now support its existence in non-human animals.
The occurrence of personality in animal populations has been widely documented; however its ecological and evolutionary consequences remain unexplored. In order to address this gap in our knowledge, it is important to combine captive experiments with observations in the wild. This approach ensures findings that reflect natural behaviour and conclusions that are ecologically relevant. However, the logistical and practical challenges of such a multi-faceted approach have led to a taxon-specific and small animal bias for personality studies.
THE PROJECT
For her PhD research, Dr. Felicie Dhellemmes used wild juvenile lemon sharks to address the ecological consequences of personality. Juvenile lemon sharks in the study site were captured in large numbers, are resilient in captivity and can be recaptured and tracked for ~4 years in the wild. Using an established methodology, Felicie tested the sharks for traits in captivity and used acoustic telemetry (to follow sharks in the wild), stable isotope analysis (diet), and DNA analysis (heritability) to investigate the link between personality and ecology. This study addresses one of the big challenges of animal personality research and provides new insights into elasmobranch conservation and behaviour. Watch the video below to hear the results!
READ THE RESULTS
Click on the buttons below to access the online journal publications. For a full PDF copy please email felicie.dhellemmes@gmail.com
Conservation Importance
Anthropogenic pressure has propagated on land, in coastal areas and in the open ocean, leading to a change in ecosystems via the disappearance of many species. Large marine vertebrates (i.e. sharks, mammals, turtles, seabirds) tend to be particularly vulnerable to this pressure due to their complex life history traits such as low fecundity, late sexual maturity, long life spawns or extended migrations. Many elasmobranch populations are threatened by directed fisheries or by-catch mortality but also by marine pollution or by habitat degradation.
Over 60 species of elasmobranchs are considered endangered or critically endangered by the International Union for Conservation of Nature and Natural Resources. Elasmobranchs are often considered as ecological keystone species in their habitats and their disappearance can lead to cascading effects affecting the whole ecosystem including lower trophic levels. For instance, just like other apex predators, sharks influence their own prey population leading to anti-predatory behaviours shaping the rest of the ecosystem (i.e. avoidance of certain areas by prey, selective foraging etc.) Given their ecological importance and the multiple threats they face, it is important to develop a better understanding of shark behaviour and personality to enhance conservation.