405_April_24

The whisker-like barbels surrounding the mouth of a striped catfish are packed with taste buds. Unlike goatfish, their barbels lack muscles and are floppy.

wobbegongs have barbels but none have taste buds: their barbels are used to feel objects or to house ampullae of Lorenzini, which are sensitive to the electrical fields generated by prey. A recent fascinating discovery has been the finding of taste buds on the leading edges of the fins of some tropical damselfishes. These small, active fishes are visual predators, feeding on plankton in bright, clear waters. It’s likely they use these taste buds to expand their sensory field, giving them the ability to detect plankton drifting by that they didn’t see.

Using taste buds localized on barbels or spread across the entire body are effective solutions to the problem of finding food in challenging environments. The recent discoveries about damselfishes remind us that we have a lot to learn about the ways that fishes sense their world in their daily quest to survive. Whenever I get frustrated by a school of goatfish stirring up the bottom and reducing the visibility I console myself with the fact that I’m watching a remarkable adaptation at work that is much more sensitive than my own very limited abilities. •

While looking impressive, the barbels near the tip of the snout and the lobes on the upper jaw of this spotted wobbegong ( Orectolobus maculatus ) lack taste buds. The taste buds of wobbegongs are located inside the mouth, throat and the gill supports.

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DIVE LOG Australasia #405 - April ‘24

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