First report of spawning and social organization in Hawai’ian Ambon Toby, Canthigaster amboinensis

Abstract

Sharpnose puffers (Tetraodontidae: Canthigasterinae) are small demersal fishes found on tropical and subtropical reefs. They are slow moving, often cryptically colored, and typically occur in low population densities (cf. Vail and Sinclair-Taylor 2011 for report of unusual mass schooling). Thus, they have been poorly studied compared with most groups of reef fishes. Indeed, of the 35 described species, spawning in the field has been reported for only 2, with the most recent report being over 2 decades ago. These include Canthigaster valentini in the Indo-Pacific (Gladstone 1987; Gladstone and Westoby 1988), and Canthigaster rostrata of the Caribbean and tropical Atlantic (Sikkel 1990). Spawning has also been reported in captivity but not in the field for Canthigaster rivulata (see Arai and Fujita 1988), and social organization but not spawning has been reported in the field for Canthigaster punctatissima (see Kobayashi 1988).