The Picasso triggerfish is a robust, grey fish with a unique, notable pattern of stripes giving it the distinct appearance of a painters colour palette - hence its name after the famous painter Pablo Picasso. It's Hawaiian name, humuhumunukunukuāpuaʻa, literally means "pig-snouted triggerfish."
This pattern has a number of unique elements, that make identifying the Picasso triggerfish easy:
- A distinct yellow strip from its mouth to just below its pectoral fins.
- A bright blue ring around the mouth.
- Bright blue and dark black stripes running from the top of its head, intersecting with the yellow stripe below the pectoral fin.
- Four white stripes crossing a black patch from the anal fin of the triggerfish to its lateral line.
- A diagonal rusty-black band from the second dorsal fin, forward until the lateral line.
- A series of small black spines on both sides of the peduncle.
It is common on tropical reefs and nearby sandy patches throughout the Indo-Pacific. The Picasso triggerfish feeds on bottom-dwelling invertebrates primarily but is an opportunistic omnivore and scavenger.
The Picasso triggerfish is highly territorial and aggressively protects its territory from large intruders - including attempts at driving away human divers. Both males and females are territorial, but males occupy larger territories, which they maintain for longer in an attempt to overlap it with the territory of a potential mate. Females have smaller territories as they protect their eggs from predators and are thus unable to travel too far away from the nesting site in search of food.
An unusual behaviour displayed by the Picasso triggerfish is its sleeping position - it will spend the night on its side, often wedging itself between corals or rocks with its dorsal and pelvic fins.
What are triggerfishes?
Triggerfish are members of the small marine fish family Balistidae. They are found around the world in tropical and subtropical waters, usually at shallow coral reefs with a few pelagic exceptions.
Triggerfish are generally small to medium-size fish, with maximum sized ranging from 20cm to one metre, depending on the species. Their bodies are compressed and oval or diamond-shaped. Their anal and dorsal fins are set far to the back, and by flapping these in unison the triggerfish is able to swim slowly, much like an ocean sunfish. Their large, crescent-shaped caudal fins are only used when a burst of speed is required to escape a predator.
The name “triggerfish” comes from their ability to lock their first two dorsal fin spines in place, creating a barb to injure the mouths of would-be predators. The locking mechanism of this barb resembles a trigger.
Their pointed heads house strong jaws that power thick teeth used for crushing armoured prey, such as crustaceans, molluscs, sea stars and urchins. Their eyes are set far back on their body, and adaptation to avoid injury from the spines of sea urchins.
Triggerfish are known to be very intelligent and adaptable, able to change strategies to exploit a variety of food sources, such as plankton, algae and small fish.
Male triggerfish are highly territorial. He will mate with females that choose to enter his territory but will fight to the death to prevent males of the same species from entering. When their young are present, male triggerfish will attack animals many times larger than themselves to protect them, including humans.