Personality affects defensive behaviour of Porcellioscaber (Isopoda, Oniscidea).
We evaluated individual behavioural patterns of isopods expressed as tonic immobility following some intrusive treatments. Common rough woodlice, Porcellioscaber, were kept individually in plastic boxes and tested for tonic immobility repeatedly. Reactivity, sensitivity (number of stimuli needed to respond), and endurance of tonic immobility (TI) according three types of treatments (touch, squeeze, drop) were evaluated. Touch was the weakest treatment and it was necessary to repeat it a number of times to obtain a response; while squeeze and drop induced TI more frequently. Nevertheless, duration of the response persisted for a longer time with the touch treatment. Within each set of the three treatment, the strongest response was the third one, regardless of treatment type. Duration of reaction was affected by the size of the woodlouse, the smallest individuals feigning death for the shortest time. Despite body size, we found a significant individual pattern of endurance of TI among tested woodlice, which was stable across treatments as well as across time (5 repetitions during a 3 week period). Porcellioscaber is one of the first species of terrestrial isopods with documented personality traits.
Department of Ecology and Environmental Sciences, Faculty of Science, Palacky University, Slechtitelu 27, CZ-77900 Olomouc, Czech Republic.
Ivan Hadrián
IH
Tuf
Department of Ecology and Environmental Sciences, Faculty of Science, Palacky University, Slechtitelu 27, CZ-77900 Olomouc, Czech Republic.
Lucie
L
Drábková
Department of Biology and Ecology, Faculty of Science, University of Ostrava, Chitussiho 10, CZ-71000 Slezska Ostrava, Czech Republic.
Jan
J
Šipoš
Anti-predatory behaviour; behavioural trait; death feigning; predation; thanatosis