ABSTRACT. – A mountainous site in central Italy (Cocullo, Abruzzi region) offers an exceptional opportunity to test whether the effects of several centuries of “manipulations” on snakes by humans (for traditional religion-linked cultural events) may have altered the reproductive phenology of free-living snakes, which is strongly seasonal in these regions. The Saint Domenico’s procession ritual takes place at Cocullo village on the first Thursday of May of each year, and has done for well over 300 years. For this ritual, local snake-hunters search for snakes throughout the woodlands around the village during April, and capture many snake specimens just before the onset of their spring mating season. The hunters set them free by mid May, after the end of the procession rituals. The species used are mainly Elaphe quatuorlineata, E. longissima, and Coluber viridiflavus. Due to the large number of specimens captured, it is likely that the pressure of the snake-hunters is very high on the local population of snakes, and that most of the adults are indeed captured each year for the procession. Reproductive seasonality of the three species targeted for the procession and of a non-target sympatric species (Vipera aspis) was studied in both the woodlands around Cocullo and in the woodland around another village, with similar eco-climatic characteristics, where no such snake hunting occurs. There was a remarkable delay in the reproductive seasonality of target species, especially of the two Elaphe (E. quatuorlineata and E. longissima), whereas no such effect was observed in the species which is not used for the procession (V. aspis). These effects (delaying of oviposition period of 20-40 days on average) were so evident, that they probably may have important consequences for other aspects of the reproductive biology of these animals (e.g., length of the reproductive cycle, reproductive frequency, etc). On the other hand, clutch size was not influenced by hunting in any species.

RÉSUMÉ. – Cocullo, dans les Abruzzes, est une localité montagneuse de l’Italie centrale qui constitue un endroit idéal pour mesurer les effets des « manipulations » humaines (tenant aux traditions religieuses locales) qui ont agi, pendant des centaines d’années, sur la fonction reproductive des Serpents. Le rite de la procession de Saint Dominique, qui se déroule début mai depuis plus de 300 ans, se base sur la capture de plusieurs dizaines de Serpents par les chasseurs de la zone qui les prélèvent avant la période de reproduction et les relâchent dans la nature fin mai. Les espèces les plus utilisées sont Elaphe quatuorlineata, E. longissima, et Coluber viridiflavus. La pression exercée par les chasseurs est assez élevée et la plupart des exemplaires adultes sont capturés avant la saison de l’accouplement. Par rapport aux Serpents d’une autre « zone de contrôle », ayant les mêmes caractéristiques bio-climatiques et environnementales mais non affectée par les prélèvements des chasseurs, les Serpents de Cocullo ont différé de façon sensible leur période de dépôt des oeufs, tandis que les autres caractéristiques reproductives sont restées pratiquement identiques.