- Scientific name: Balistes capriscus
- Also known as: Grey Triggerfish
- Size: Up to 2ft and 6lbs.
- UK minimum size: Data Unavailable
- UK shore caught record: 5lb 14oz
- IUCN Status:
- Global: VU (Vulnerable)
- Europe: DD (Data Deficient)
- Distribution: Found primarily in the warmer waters of the world. Can be caught found the south of the British Isles in the summer, and range appears to be expanding.
- Feeds on: Mostly shellfish and crustaceans, although will feed on other food sources which are present.
- Description: Strange looking fish with oval shaped, laterally compressed body. Eyes are set high up and far back. Dorsal fin is spiky and also set far back. Skin is hard and rough, usually greyish in colour, although can be streaked with other colours. Mouth is small.
- Additional notes: The information above is for the Grey Triggerfish which is the species most likely to be encountered in UK waters.
There are around forty species of triggerfish around the world, with most being brightly coloured species which are resident in tropical and sub-tropical waters.However, the grey trigger fish is found in UK waters. As recently as 2005 a triggerfish being caught in British waters made national news, but now triggerfish are being caught in the UK more and more often, to the extent that they are approaching near-common status in certain areas around the southern parts of the British Isles and there is evidence to suggest that they are making their way northwards.
The grey triggerfish is found throughout the tropical and sub-tropical waters of the world, although it is being found in cooler, temperate seas on an increasing basis. This species can be found throughout the Mediterranean and the Black Sea, with its range extending to the coastline of African and throughout the northern parts of the Atlantic Ocean. It is at the edge of its distribution along the coastline of the southern parts of the British Isles, and is absent from the colder waters of the Nordic countries and the Baltic Sea. It can also be found along the coastline of North and South America, in Caribbean waters and in parts of the Pacific Ocean.
Habitat, Behaviour and Feeding
Triggerfish favour fairly shallow water, certainly no deeper than thirty metres. They feed on shellfish and crustaceans, using their small but extremely powerful jaws to crunch through the shells of the creatures they feed on. For this reason triggerfish are found around stony and broken ground which has a high population of shellfish, invertebrates and crabs for them to feed on. Triggerfish get their name from their spiny dorsal fins. This fin is erected as a means of defence against predators. The first dorsal fin is raised and the second part of the dorsal fin fits into a groove to keep the spine raised up. The second part can be pressed down (like a trigger) to lower the spine.
Divers have found triggerfish to be inquisitive and unafraid when approached. However, they can be territorial and aggressive, especially when guarding nests during breeding season. They can swim at divers and attempt to drive them away if they get to close to the nest. While the grey triggerfish found in UK waters is too small to harm humans the larger triggerfish found in tropical waters are more dangerous. The titan triggerfish (Balistoides viridescens) can attack divers and bite hard enough for the victim to require medical attention.
Despite the rough skin and firm flesh the grey triggerfish is edible and is quite highly regarded as a table fish. The same is not true of all triggerfish species, with the flesh of certain species causing ciguatera poisoning when consumed. Grey triggerfish have suffered from declining numbers across much of their range due to overfishing from both commercial and recreational fishers. The International Union for the Conservation of Nature states that grey triggerfish have reduced significantly in abundance in African and North and South American waters, meaning this species is classed as Vulnerable on a global basis. In Europe the situation is less clear and further research is needed into this species, meaning it is classed as Data Deficient.
Methods and Techniques to Catch Triggerfish
With triggerfish not common in the UK anglers often catch them when targeting other species. However, in areas around the south where trigger fish have been reported it can be worth specifically trying for a this species in the summer months. Deep water rock marks or piers which cast onto broken and rough ground are the top marks. Many triggerfish are caught on baits presented on the seabed, but deep float fished baits can also produce good results, especially if they are allowed to slowly drift around the area with the tidal flow where the triggerfish are feeding. In deep-water rock marks freelining down a bait can work, as triggerfish will come very close in to feed on both mussels and all kinds of shellfish which attach themselves to rocks.
When it comes to bait mussels and peeler crabs are the most obvious fish due to the triggerfish’s natural diet of shellfish and crustaceans. However, they are opportunistic feeders and other baits such as mackerel strip, ragworm and squid will also catch. Indeed, mackerel (being used to target other species) probably accounts for more triggerfish catches than any other bait. The trigger fish has a very small mouth so hook sizes should be kept correspondingly small at size 1 or 2. Remember though that the triggerfish has powerful jaws and teeth, and is a decent fighter, so hook patterns should be kept strong and hooklengths made of 30lb monofilament line or stronger.