As reported by a study published in the British journal Biology Letters, herrings pass gas on porpoise in order to communicate with each other. Individual fish use what the researchers call "FRTs" (fast repetitive ticks) when darkness falls to let other members of the school know where they are so that the school can stay together and not flounder around. The FRTs are the sounds resulting from gaseous expulsions through a duct next to the fish's anus.
Contrary to the gas passed by humans, which comes from both swallowed air and the fermentation products of bacteria in the colon, the driving force behind herring FRTs consist solely of air swallowed by a fish from the surface of the water and then stored in its swim bladder. It is thus not particularly malodorous (in fact, you might say that it is not smelt at all). The concept of SBD ("silent but deadly") is a total anathema to a herring fartiste.
The herrings engage in these melodies only when it is dark and only when the density of the population reaches a certain level. The sounds are usually in the range of up to 22 kilohertz and are audible to herring but not to most other species of fish (who apparently either have a poor sense of herring or else just simply tuna it out). They thus provide a means of signaling other herring without provoking piscine predators.
For further information on this topic, check out the National Geographic News.
Oh my! A pun-mine at every turn. Well done!
ReplyDeleteI just hope that they weren't too crappie.
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