BULLETIN OF MARINE SCIENCE. 00(0):000–000. 0000 doi:10.5343/ 763 Bullein of Marine Science © 2011 Rosensiel School of Marine and Atmospheric Science of the University of Miami Bulletin of Marine Science © 2014 Rosenstiel School of Marine & Atmospheric Science of the University of Miami Portraits of Marine Science Bull Mar Sci. 90(3):763–764. 2014 http://dx.doi.org/10.5343/bms.2014.1006 Observation of macroalgal browsing in juvenile humphead parrotish, Bolbometopon muricatum, in the Spermonde Archipelago, Indonesia Jeremiah G Plass-Johnson * , Sebastian CA Ferse, Christian Wild, Mirta Teichberg Leibniz Centre for Tropical Marine Ecology, Fahrenheitstraße 6, 28359 Bremen, Germany. * Corresponding author email: <jeremiah.plassjohnson@zmt-bremen.de>, phone: +49 (421) 23800 113. In the Indo-Paciic region, the humphead parrotish, Bolbometopon muricatum (Valenci- ennes, 1840), is among the most important and charismatic ishes inhabiting coral reefs. It is one of the largest and oldest growing ishes with adults reaching 45 kg and 130 cm at 40 yrs of age (Bellwood and Choat 2011). Generally, they are found in groups of up to 30 individu- als, and like most parrotishes, they feed from the reef’s carbonate substratum. However, B. muricatum is unique in its mode of feeding, which includes predation on live coral and the excavation of large amounts of carbonate substrate. In the Australian Great Barrier Reef, B. muricatum contributes disproportionally to bioerosion processes, with the capacity of one individual to ingest 5 t of carbonate yr −1 (Bellwood et al. 2003). his feeding redistributes ap- proximately 32.3 kg m −2 of sediment yr −1 , clearing space for new recruitment and reshaping benthic community composition (Bellwood et al. 2003). Nearly half of the ingested sediment consists of live coral (Hoey and Bellwood 2008), suggesting coral predation as another impor- tant functional role for the species. Bolbometopon muricatum’s large size makes it a ishery target and its late maturation makes it susceptible to overishing. As a result, it has been greatly overharvested throughout most of its geographical range (Bellwood et al. 2012). Currently it remains in good numbers at only a few places (Bellwood and Choat 2011). However, even in places where it receives the great- est protection (e.g., Great Barrier Reef), the species’ size distribution is heavily truncated, with only approximately 5% below 45 cm in length, indicating low recruitment (Bellwood and Choat 2011). Generally, because of B. muricatum’s scarcity, studies of its biology and ecology are anecdotal and based on the more conspicuous adults. here is a paucity of information concerning early life stages, and given their low numbers, a greater understanding may help in their conservation. On October 2, 2013, at Kapoposang Reef, South Sulawesi, Indonesia, B. muricatum, dis- playing juvenile colouration (approximately 40 cm), was observed feeding on the macroalgae genus Padina during a remote underwater video transplant assay (left panel). hese assays