Long-term and short-term effects of temperature on snake detectability in the wild:: a case study with Malpolon monspessulanus

The relationship between temperature and rates of detection of the Mediterranean snake Malpolon monspessulanus (Montpellier snake) in the wild was analysed over a 26-year period. We used records of live and freshly road-killed snakes in south-eastern Spain. A short-term effect of temperature on rates of snake detection was found: the higher the yearly temperature, the higher the snake detectability was that year. Moreover, a long-term effect of temperature on snake detectability was found, as snake abundance in year x was also strongly affected by temperature during year x-1 and x-2. A multiple-regression model demonstrated that these effects were independent. These long-term effects are probably due to an effect of temperature on snake population dynamics.