[eng] Climate change is increasingly impacting species and communities around the globe.
Ocean warming is particularly threating for marine ecosystems and many species of
marine invertebrates are especially sensitive to raising temperatures. We studied the
behavioural response of the purple sea urchin (Paracentrotus lividus), a common
herbivore of the Mediterranean Sea, to a thermal regime by performing an experiment
under controlled laboratory conditions. We evaluated changes in weight and the behaviour
of sea urchins after 11 days of exposure to four targeted temperatures under a sublethal
range (20, 23, 26, and 29 ºC). Sea urchins modified their behavioural responses when
exposed to increasing temperatures, while no significant results for changes in weight
were found. Increasing temperatures induced higher mobility and activity, while longer
times were required for the righting response. These results suggest a strong temperaturedependence of the behaviour of P. lividus and reveal the need for further studies on
consequences of climate change on marine invertebrates.