Araucaria araucana and the Austral parakeet:: pre-dispersal seed predation on a masting species

Pre-dispersal seed predation by Austral parakeets, Enicognathus ferrugineus, on pehuen, Araucaria araucana, was Studied to assess the relationship between predation and seed production. We collected failing seeds in four araucaria forests of southwestern Neuquen Province, Argentina during four years that included both mast and intermast years. Predation rates were negatively correlated with seed production. When seed production was high. predation rates ranged from 0.6 to 3.3 %; when it was low, predation rates ranged from 13.0 to 20.6 Years differed in the pattern of monthly seed fall with peak seed fall in March 2002 and April 2003. Predation rates were lower and more uniform in the year of higher seed production, but did not differ between sites. In an intermast year, predation rates increased during the season, reaching their highest rates after peak seed fall. Parakeets handled seeds differently in mast and intermast years, dropping fewer slightly-damaged seeds when production was low. We discuss these results in the context of the predator satiation hypothesis.