A non invasive method for the study of the sex-ratio in a population of Myotis myotis and Myotis blythii (Chiroptera) in Piedmont region (Italy)

Abstract

This study contributes to the knowledge of demographic structures of the two sympatric, sister species Myotis myotis and Myotis blythii (Chiroptera). The sites investigated were the Abbazia di Santa Maria in Staffarda and the Castello Ducale in Agliè, known to accommodate the larger Myotis colonies in North-Western Italy. Sampling were conduced in summer 2006. During this season tens to hundreds of females gather togheter to form the so called nurseries, composed by mothers with their litters. With the end of summer, males reach the nurseries for mating. Since these species are severely endangered of extinction, we adopted a non-invasive, opportunistic sampling method based on collection of feces, although tissues from died specimens were harvested as a control of the method. Total DNAs extracted from stool samples were amplified using a pair of specific primers for the DBY8 locus on the Y chromosome, along with an internal control shared by both sexes. The results showed that the colony located in the Abbazia di Staffarda is a typical nursery, while in the Castello di Agliè the situation in composite, because sorting of individuals describes this latter community as both a nursery and a reproductive colony.