Response of a Scarlet Macaw Ara macao population to conservation practices in Costa Rica

The Central Pacific Conservation Area contains one of Costa Rica’s two viable, but threatenedScarlet Macaw Ara macao populations. For 14 years (1990-2003), we monitored the size of thispopulation. Non-linear models fitted to 1990-1994 observations revealed seasonal and longtermchanges in population size. The peak of annual population size occurred in August, with acyclic range of about 90 birds between the lowest and highest points of the annual cycle. Thebest model also revealed a decline in population size of approximately eight birds counted peryear or 4% of the total population per year (1990-1994).

CHRISTOPHER VAUGHAN, NICOLE M. NEMETH, JOHN CARY andSTANLEY TEMPLE, Bird Conservation International (2005) 15:119-130