Longnose butterflyfish. Image by Nick Hobgood via Wikimedia Commons.
'Tad', the longnose butterflyfish (Forcipiger flavissimus) has a pretty small part in 'Finding Nemo'. But these fish are stunning and interesting, and since we keep them in the aquarium at World Museum, it would be a shame not to mention them due to Tad being a bit-part.
The most striking feature of Yellow Longnose butterflyfish are their long noses. This long snout can be poked into little holes and crevices in rocks amongst corals to pick at small copepods and worms and the small crustaceans living in them. We keep our longnose in with rocks and corals, so they’re able to pick out foods. They will also feed on brine shrimp and chopped up mysis, which we defrost each morning and enrich with more nutrients. They also use their snouts to pick at the tube feet of starfish, so we don’t house them with starfish!
Young longnose butterflyfish can be found in groups of five, but when they become adults they are found in monogamous pairs, claiming their own territory in the reefs amongst the corals. They’ll stick together; males will fend off other male intruders when they are paired with a female, and females will fend off other females who may be trying to edge in on their food resources. It’s difficult to sex fish, so it’s best to be wary about getting a pair of longnose butterflyfish, because if you were to get two males or two females they would end up fighting. We keep our longnose in with another member of the Chaetodontidae family - the Copperband butterflyfish (Chelmon rostratus). Though they’re the same family, they’re not the same species and are less likely to be aggressive towards each other. Copperbands are notorious for being bad feeders in captivity, so when paired with a longnose who is less shy about acquiring food, they soon learn to eat the brine shrimp and mysis that is dropped in their tank.