MATING BEHAVIOUR OF POLYGYNOUS AND MONOGAMOUS ROCK SPARROW MALES IN AN ALPINE POPULATION

Differences in mating effort behaviours (i.e. mate guarding and singing) in Rock Sparrow (Petronia petronia) males of an Alpine population (Susa Valley, Western Alps, Italy) were evaluated with three mate guarding indexes and singing rate analysis. These metrics were used to compare the different mating strategies adopted by males (monogamy, polygamy, successive polygamy; i.e. when a male has only one mate for the whole reproductive season, or more than one, or one after another with no overlap in the fertile period). Analyses were performed on two time frames: inside and outside of the fertile period of the social females. Polygamous and monogamous males responded similarly in terms of mate guarding and singing rate compared to successive polygamous males, that altered their behaviour during the fertile period of the female. This could be explained because successive polygamous males tend to spend more time in looking for their next mate. The main difference between mating strategies lies not in the mating effort for each nesting event, but in the seasonal-long investment.