Protected by dragons: Density surface modeling confirms large population of the critically endangered Yellow-crested Cockatoo on Komodo Island

Research confirms that Komodo National Park (KNP) harbors a significantly larger population of the critically endangered Yellow-crested Cockatoo (Cacatua sulphurea) than previously estimated, with approximately 1,113 individuals residing on Komodo Island. This finding challenges prior conservative estimates and underscores KNP's role in preserving Indonesia’s rarest cockatoo species, likely due to its protection of the iconic Komodo dragon (Varanus komodoensis). The study employed density surface modeling (DSM), combining distance sampling with topographic and habitat data to predict local densities. High-density hotspots were identified in wooded valleys, with DSM predictions validated by independent observations (93% accuracy). Annual counts by KNP staff also showed population growth from 2011 to 2017, reinforcing the effectiveness of conservation efforts. This is the first application of DSM to a critically endangered species, demonstrating its potential for identifying abundance hotspots and estimating global populations in threatened taxa.

Reuleaux, A., Siregar, B. A., Collar, N. J., Panggur, M. R., Mardiastuti, A., Jones, M. J., & Marsden, S. J. (2020). Protected by dragons: Density surface modeling confirms large population of the critically endangered Yellow-crested Cockatoo on Komodo Island. The Condor, 122(4). https://doi.org/10.1093/condor/duaa042