News item submitted by
News item dated
17 Mar 2011
Our volunteers at Mafia Island, Tanzania have been busy carrying out underwater surveys along the coral reefs. The triggerfish which makes up the family Balistidae has been particularly abundant this past month, this is great news for the marine ecosystem. They are also a very visually attractive species, one of my favourites - lucky divers!
Triggerfish are listed as vulnerable or facing a high risk of extinction in the wild on the IUCN website and are normally one of the first species to disappear due to overfishing. So the fact that they are being frequently sighted shows that recovery is occurring. Healthy numbers of triggerfish is important in maintaining low levels of crown-of-thorns starfish (COTS) and sea urchins. Theses species feed on coral polyps and if numbers are too high due to depletion of their predators, will lead to the irreversible damage of coral species.
Triggerfish get their name due to their ‘trigger’ spine which is erected to deter predators. They are also quite distinct due to their big head, small projectile mouth and compressed body. They are capable of boring open mussels and other hard shelled invertebrates with their powerful jaw and eight teeth. But don’t approach a mother triggerfish when she is looking after her eggs though, as they are known to nip divers which get too close!
Fancy joining our Tanzania team to help with marine conservation whilst having the opportunity to dive in crystal clear waters? Find out more here