Annual variation in reproductive activity and productivity of the Thick-billed Parrot (Rhynchopsitta pachyrhyncha)
We studied annual variation in reproductive activity and productivity of the Thick-billed Parrot (Rhynchopsitta pachyrhyncha) during a five year period (1997-2001), in five nesting areas at the Sierra Madre Occidental in Mexico. Two breeding areas continue to be the breeding strongholds for the species. We documented 491 nesting pairs and determined the outcome of 162 accessible nests. A nesting pair laid in average 2.7 eggs, and produced 1.6 fledlings per egg-laying pair.