First Report on the Density and Size Frequency Distribution of the Napoleon Wrasse, Cheilinus undulatus in the Tubbataha Reefs Natural Park, Philippines

A significant discovery reveals that the Tubbataha Reefs Natural Park (TRNP) serves as both a source and sink habitat for the endangered Napoleon wrasse (Cheilinus undulatus), locally known as 'mameng.' The study, conducted in May 2017 using fish visual census techniques across 103 hectares of less-touristed reef areas, recorded an average density of 6.83 individuals per hectare, with the South Atoll showing higher densities (8.13 ± 1.11 SE) compared to the North Atoll (4.20 ± 0.46 SE). However, the North Atoll's Napoleon wrasse population was significantly larger, with a median size of 65 cm versus 60 cm in the South Atoll. The presence of juveniles in the North Atoll further supports its role as a critical habitat for this species, listed under IUCN Red List and CITES Appendix II. These findings underscore TRNP's importance in the Sulu Sea and adjacent regions, potentially facilitating population resilience through pelagic larvae dispersal.

Nañola, C., Paradela, M. A., Songco, A., Pagliawan, M. R., Alarcon, R., & Santos, M. (2020). First Report on the Density and Size Frequency Distribution of the Napoleon Wrasse, Cheilinus undulatus in the Tubbataha Reefs Natural Park, Philippines. Philippine Journal of Science, 150(1). https://doi.org/10.56899/150.01.18