Lagoon Triggerfish – Profile | Traits | Diet | Breeding | Facts

Lagoon triggerfish

The lagoon triggerfish, scientific name Rhinecanthus aculeatus, also referred to as the black bar triggerfish, the Picasso triggerfish, or the Picassofish, is a triggerfish, as much as 30 cm in size, discovered on reefs within the Indo-Pacific area.

Lagoon triggerfish profile

The Hawaiian name for the fish, humuhumunukunukuāpuaʻa, additionally spelled humuhumu-nukunuku-a-puaʻa or simply humuhumu for a brief (which means “triggerfish with a snout like a pig”) is shared with the reef triggerfish (R. rectangulus), the state fish of Hawaii.

This species has been studied in a range of analysis contexts, from locomotion to paint vision analysis.

Like most fishes, the reef triggerfish undergoes heterosexual reproduction, during which there are separate female and male parents. Reef fishes are egg-layers, and the eggs are externally fertilized by the male parent.

Nests are constructed by the feminine parent, during which the eggs are fertilized and cared for till they hatch. The newly-hatched younger are additionally taken care of by the feminine parent.

The reef triggerfish swims in a real attribute method, propelling itself by way of the water utilizing waving motions of the broadened dorsal and anal fins, permitting it great maneuverability.

The reef triggerfish has the flexibility to maneuver ahead, backward, or hover above the reef. The presence of a robust, broom-like tail permits the reef triggerfish to sprint shortly into the reef when confronted with hazard.

When encountering predators, reef triggerfish utter grunting noises. It has been speculated that these sounds work to warn different triggerfish of the present hazard.

lagoon triggerfish

When retreating to the reef in response to hazard, a reef triggerfish wedges itself right into a gap by elevating the massive dorsal backbone. A second, smaller dorsal backbone locks the first in place.

Yet one other anal backbone helps the fish to enter the shelter. This behavior can also be typically utilized at night, as a reef triggerfish needs to relax inside a reef. When resting, the reef triggerfish sleeps on its facet.

Considered to be one of much more aggressive of the triggerfish, the reef triggerfish additionally typically shows this aggression towards members of its personal species along with different fish which can be comparable in size.

The territorial reef triggerfish typically emits a whirring sound when startled. It is just not simply approachable and retains a good distance from different organisms.

The vocal reef triggerfish has the flexibility to make a snorting noise when dropped at the floor, as its defensive puffing method is lowered.

This distinctive capacity has given the reef triggerfish its Hawaiian widespread name of Humu-humu-nuku-nuku-apu’a, which straight interprets to “Fish who comes out of the water and sounds like a pig”.

In the wild, the territory of the male triggerfish will often overlap with a number of breeding females. The male will create a harem around himself to breed within the course of the mating season.

The fish typically spawn at daybreak, the place the male will fertilize the eggs after which go away from them within the care of the feminine. Then the male strikes on. This process requires an especially great amount of territory that isn’t possible to recreate in-tank environments.

The humu humu triggerfish is just not a choosy eater. This fish is, for essentially the most half, carnivore. Their natural meals are: clams, snails, shrimp, krill, squid, and so on., and can need to be fed meaty meals to outlive.

Because their teeth will continue to grow, you need to present them some meals, with shells, that may put on down their teeth. This may be within the type of frozen meals or live meals. Try to fluctuate the kind of seafood you feed the R. aculeatus to supply them with a diversified diet.

Rhinecanthus aculeatus also referred to as the picasso triggerfish or humu humu.

Picasso triggerfish are aggressive. No need to mince phrases there–they’re solely appropriate for a tank with different aggressive fish.

You must also simply regulate issues when you have got your palms within the aquarium as a result of in addition they have giant teeth and highly effective jaws, designed for crushing the shells of their meals.

It’s not very possible that you’d get bitten, but it surely’s undoubtedly worth retaining a monitor of all of your digits whereas your hand is within the tank.

The Picasso triggerfish is a daring, stunning, aggressive fish that’s enjoyable to look at and straightforward to maintain alive, however extraordinarily territorial.

They develop fairly giant (10 inches) and require a big tank. They are incompatible with almost any reef invertebrates, consuming the mobile inverts and knocking over the others.

With that stated, if you wish to have a really cool fish-only aquarium, this brightly colored fish will study to acknowledge you while you feed it, the state fish of Hawaii might be a great selection.

lagoon triggerfish

Lagoon triggerfish Geographic Range

Considered to live within the Indo-Pacific area, reef triggerfish transverse all kinds of marine areas from thirty degrees north to south in latitude. Reef triggerfish prolong from the Hawaiian islands southward to Polynesia and Australia, westward by way of Micronesia and Melanesia, by way of the East Indies together with the Philippines, throughout the Indian Ocean, to the coast of Africa and the Red Sea. More particularly, reef triggerfish occupy the Red Sea south to South Africa, east to the Hawaiian, Marquesas, and Tuamotu Islands, north to southern Japan, south to Lord Howe Island, Micronesia, and the Eastern Atlantic from Senegal to South Africa.

Lagoon triggerfish Physical Description

A reef triggerfish is well distinguished by its angular body, distinctive shade pattern (resembling blocks of colors), fin association, and attribute dorsal backbone.

This ahead backbone on the dorsal fin lies barely above and behind the attention. It could be very sturdy and inflexible, serving as protection adaptation.

When this backbone is raised, it typically locks on this protecting place, giving the triggerfish its name. Altogether, there are three dorsal spines, twenty-three to twenty-six dorsal softrays, twenty-one to twenty-three anal soft rays, and no anal spines.

Considered to be sturdy and well-built, the reef triggerfish reaches a maximum size of thirty centimeters. It has a small however highly effective jaw, outfitted with sharp, slicing teeth.

The eyes of a reef triggerfish are set atop the pinnacle, transferring independently, in order to scan the reef for possible predators and prey.

lagoon triggerfish

Lagoon triggerfish Habitat

The Picasso Triggerfish may be discovered within the Indo-pacific ocean and the red sea. Most generally it may be seen around Hawaii, Polynesia, and the Philippines.

This fish tends to be discovered within the sandy components of reefs swimming round actively and usually present in more shallow components of reefs, the place there are rocks for it to cover away in. It’s the official fish of the state of Hawaii.

The reef triggerfish is mostly present in shallow outer reef habitats. Swimming alongside the underside in quest of meal gadgets, it’s discovered on surge-swept basalt reefs.

The reef triggerfish is usually present in subtidal reef flats and guarded lagoons. This marine fish often occupies water with salinity ranges starting from 1.020 to 1.023, and water temperatures from seventy-seven to eighty degrees Fahrenheit.


Body compressed with an elongated head. Blueline above the higher lip. Smallmouth with the yellow space surrounding the mouth and increasing to the bottom of pectoral fin. Dark thick black banding close to the lateral line with smaller banding extending ventrally. Dorsal fin III, anal fin 0, pectoral fin (13-14).


This species has one kind of single cone (SC), with visible pigment peaking in sensitivity at 413 nm (S), and a double cone with totally different visible pigments in every member peaking at 480 nm (M) and 530 nm (L) respectively.

Behavioral analysis has offered proof that particular person members of the double cones can act as unbiased channels of shade information, aiding in understanding double cone function. This analysis suggests the species has trichromatic vision, like people.

lagoon triggerfish


Lagoon triggerfish live within the reefs and sandy areas of coral reefs, the place they eat absolutely anything that comes alongside.

They are at all times restlessly swimming round and vigorously defend their territory towards intruders, together with divers, particularly when guarding their eggs throughout reproduction season.

Their comparatively small size makes them a lot much less harmful than the bigger titan triggerfish of the same family.

Food Habits

The reef triggerfish diet consists primarily of reef invertebrates and algae. Common meal gadgets are small crustaceans, worms, brittlestars, sea urchins, and snails.

Less widespread dietary supplements are different fishes, corals, tunicates, forams, and eggs. Highly versatile in its feeding potentialities, the reef triggerfish will feed on all kinds of crustaceans, molluscs, and fish. Reef triggerfish receive their meals primarily by rooting by way of sand or rocks

Lagoon triggerfish Compatibility

The Picasso triggerfish is NOT REEF SAFE. They like to eat invertebrates. Skunk cleaner shrimp, peppermint shrimp, any form of crab or shrimp, and even Nassarius or Cerith snails can be on their menu.

Even in the event that they aren’t consuming your inverts, they could knock down or in any other case terrorize your corals. They will assault much less aggressive fish.

So they’re greatest stored in a fish-only tank with different aggressive fishes, just like the snowflake eels, Lionfish, and equally sized surgeonfish.

Although solitary, some fish keepers have had success with retaining a number of Picasso fish in a tank when launched as juveniles. Remember to test the tank every day to verify there isn’t bullying happening in your community.

Another necessary tip can be to keep away from including fish (even aggressive ones0 which can be considerably smaller than your humu humu.

lagoon triggerfish

Lagoon triggerfish Mating and reproduction

Both sexes guard territories, some sustaining a territory for eight years or longer (with males holding territories for considerably longer than females).

A typical male territory might overlap with one to 5 feminine territories, and their mating system is described as haremic, though not a lot is thought about this (comparable mating programs are seen in different Balistidae species).

If a male or feminine is eliminated or disappears their territories are quickly taken over by a brand new fish. They reproduce a number of occasions over their lifetimes.

Pair-spawning takes place around dawn, with the egg lots being hooked up to sand, coral rubble, or algae. They hatch on the same day around sunset.

Although paternal care is regular in teleost fishes with exterior fertilization, it’s the moms on this species that guard and takes care of eggs till they hatch.

The mom stays above the eggs for about 12–14 hours, fanning the eggs along with her pectoral fins to enhance aeration for maybe 30% of the time.

She chases away most fish that strategy and takes away different intruders like starfish by mouth. Maternal care is efficient in stopping predation, and experimental removing of the moms lowered survival to nearly nothing suggesting this behavior is adaptive.

Unlike fathers, moms forage much less and over a smaller space close to the egg mass whereas caring for the eggs.

Since the males have a number of mates, caring for an egg mass would in all probability be more expensive by way of lost mating alternatives so maternal care is taken into account to be an evolutionarily stable strategy.


Great tankmates for a Picasso triggerfish can be bigger, aggressive fish (or different fish that may not be threatened by their aggression) like Dog-faced pufferfish, Snowflake eel, Ribbon eel, or Foxface rabbitfish.

lagoon triggerfish

Lagoon triggerfish Ecology

The species inhabits shallow lagoonal reef flats usually dominated by sand to a depth of about 4 meters. It is quite common within the native range and feeds on quite a lot of benthic organisms together with fishes, sea urchins, crustaceans, polychaetes, gastropods, ostracods, sipunculids, and algae.

It can also be very territorial and can have interaction in intra- and interspecific border fights, typically making pig-like grunts when disturbed.

The species is haremic with male territories overlapping with roughly two or three feminine territories. Both women and men keep territories for long durations, with some documented over eight years. Pair-spawning happens around dawn and females take care of the demersal eggs till hatching.


Currently considerable in many marine environments, the reef triggerfish is just not presently in danger. However, main alterations are occurring in many of those habitats, carrying the potential to tremendously cut back their numbers.

In addition to tropical fish collectors, human population growth and the elements that accompany it pose threats to reef triggerfish, in addition to different marine fishes and organisms.

Though presently not in danger, different organisms in many of the reef triggerfish’s habitats are being tremendously lowered by abiotic elements.

More Interesting Articles

Leave a Reply

Your email address will not be published. Required fields are marked *