Does selective predator control improve red-legged partidges (Alectoris rufa) survival? An experiment in northern Spain

Resumen del trabajo presentado al XXXth International Union of Game Biologists and Perdix XIII, celebrados en Barcelona (España) del 5 al 9 de septiembre de 2011.The purpose of the present work was to evaluate the effectiveness of selective predator control as a method to improve the survival of red-legged partridges (Alectoris rufa). The study was carried out during 2008 and 2009 in two hunting estates of Navarra (northern Spain), where two treatment zones were considered depending on the predator control. Red foxes (Vulpes vulpes) were selectively controlled during the first year in one of the zones (“predator control zone”, hereinafter PC Zone), while no control was applied in the other zone (“not predator control zone”, hereinafter NPC Zone). In 2009, treatments were inverted between zones. We radio-tracked 89 adult partridges in all study areas, which allowed us to locate 45 partridge nests and 31 broods. We captured and radio-equipped 108 partridge chicks of two different ages: 46 chicks few days after hatching and 62 chicks over one-month old. We estimated the effect of predator control on the survival rates of adult partridges, their nests and their chicks using program MARK 4.0. According to Akaike information criterion predator control was not included in the preferred models of adult and nest survival rates. Although predator control was not included in the preferred models explaining survival rates of youngest chicks, estimated survival rate was slightly higher in the PC than in the NPC zones. Contrarily, predator control improved survival rates for one month old chicks, and it was included as a factor of the most preferred models. Consequently, predator control did not improve survival rates for adult and nesting partridges, but it improved chick survival, especially for chicks over one month old.Peer Reviewe