Great tit (Parus major) breeding in fire-prone oak woods: differential effects of post-fire conditions on reproductive stages

Abstract

Wildfires negatively affect the overall reproductive success of several woodland avian species, but there is scarce information about which stages of the nesting cycle are specifically affected. We conducted a 3-year study to identify the effects of fire on the reproductive parameters of the great tit (Parus major) and the survival of its nests at different stages of the nesting cycle. We recorded the occupancy rate, clutch and brood size, hatching, fledging and nesting success in nest boxes placed on study plots with different post-fire age. By examining the post-fire succession, we analysed the survival of eggs and nestlings under predation risks. As the forest matured after a wildfire, tits occupied more nest boxes and laid more eggs that suffered less predation than in earlier successional stages. Although the incubation fate improved at each step of succession, the conditions to fully raise nestlings seemed to be suitable only in the oldest woods. Our findings indicate that the population dynamics of a reputed generalist avian species may be affected by fire. Furthermore, the effects of wildfires on stage-specific reproductive parameters show that an avian species that inhabits woodlands regains its full productivity only when its habitat has completely recovered from fire.