First record of two marine fish species from the northern Bay of Bengal, Bangladesh

The present study reports a new record of two marine fishes Filimanus similis (Feltes 1991) and Naso unicornis (Forsskål 1775) from Bangladesh waters. The specimens were collected from Saint Martin’s Island and Cox’s Bazar fish landing canter, Bangladesh. The specimens were diagnosed by analyzing their morphometric characters and DNA barcoding. The study also reports Naso as the first species of the genus ever recorded in the marine waters of Bangladesh.

Standing Out in a Big Crowd: High Cultural and Economic Value of Naso unicornis in the Insular Pacific

Hundreds of fish species are harvested in coral-reef fisheries in the Indo-Pacific region using a variety of fishing gears. This diversity makes the economics, ecology, and management of reef-associated fisheries inherently complex. However, across insular fisheries spanning the tropical Pacific, one species consistently dominates contemporary fisheries catch: the bluespine unicornfish (Naso unicornis, Acanthuridae). I evaluated the relative contribution of N. unicornis to commercial fisheries in the insular Pacific region from long-term (>1 year) fishery surveys across various jurisdictions and provide evidence of the contemporary cultural value of this species. Overall, evidence suggests that N. unicornis is the most commercially-valuable reef-associated fish species across the insular Pacific. This notion, coupled with a diverse representation of N. unicornis across Pacific cultures, suggests that the species is presently underappreciated in its role in coastal fisheries across Pacific Island nations.

Age and growth of bluespine unicornfish (Naso unicornis): a half-century life-span for a keystone browser, with a novel approach to bomb radiocarbon dating in the Hawaiian Islands

Bluespine unicornfish (Naso unicornis) from Hawaii were aged to >50 years using cross-sectioned sagittal otoliths. Fish length was a poor indicator of age because of rapid and variable early growth, exemplified by fish aged to be 4 years near maximum length. Growth was deterministic with adult ages decoupled from body length. Otolith mass and thickness were evaluated as proxies for age and both were encouraging; thickness explained more variance but mass was easier to measure. An age estimation protocol was validated through ontogeny using bomb radiocarbon (14C) dating. Use of the postbomb 14C decline period from a regional reference chronology enabled age validation of young fish — a novel approach for the Pacific Ocean. A probabilistic procedure for assigning bomb 14C dates (CALIBomb) was used for the first time to determine fish birth years. The age-reading protocol was generally validated, and it was possible to describe length-at-age despite difficulties in counting otolith annuli beyond 30–40 years. Growth curves differed between the sexes, and a four-parameter generalized von Bertalanffy growth function provided the best fit.