Environmental correlates of life history pattern in ground-beetleson Tenerife (Canary Islands)

摘要

The spatial and temporal structure of Carabus (Nesaeocarabus) interruptus Dejean, 1831 populations andthe independent effects of climate along attitudinal gradients in the island of Tenerife, especially whetherenvironmental preferences constrains the species breeding patterns at local and regional scales wereevaluated. Ground-beetles were sampled with twenty-one pitfall traps in each of the forty-one plotsduring one year study. Some sampled specimens were dissected and dried to determine sex, weight andovarian maturation. The populations were restricted to the middle climatic zone (600-1700 m). Therewas a long adult activity period from October to June and the changes in the weekly capture success werestrongly correlated with the rainfall and temperature. Overall the males during winter were more activethan the females. The emergence of new adults occurred only in spring and the body dry weight peakedin April-May. From start of autumn the weight was recovered to the initial values of the cycle, increasedand peaked in January. The females prolonged its oviposition period from mid-autumn to the starting ofspring. The species showed a winter breeding pattern and the seasonal variations in multiple life historytraits could correspond with the changing conditions of the microclimatic variables. An evolutionaryecological model could help explain the life history pattern variability among the Carabus species inSouth-western Europe. The species could tackle the geographic dispersion of their populations for thesingle purpose of seeking a suitable hydrothermal environment (high rainfall and mild temperatures) ifthe food was insured.