Labroides dimidiatus, commonly known as Bluestreak Cleaner Wrasse, is among the most commonly spread cleaners on tropical corals. We should point out that there are many Cleaner Wrasse species, but we will refer to the Bluestreak Cleaner Wrasse as it is the most prevalent of its species.

Distributed across coral reefs from French Polynesia to Eastern Africa and the Red Sea. In a symbiosis interaction that offers food and protection for the wrasse as well as significant health benefits for the other fishes, it consumes pests and necrotic tissue from the skin of larger species. The Bluestreak Cleaner Wrasse is an important addition to its ecosystem.

Appearance

Bluestreak Cleaner Wrasses can grow up to a maximum of 4 in length; they are relatively small fish. Bluestreak Cleaner Wrasses have a vivid blue color with a wide, jet-black track that extends from the apex of the head to the end of the tail. The band is narrower at the anterior portion and progressively gets wider as it moves toward the tail’s distal edge. 

Close up of a Bluestreak Cleaner Wrasse
Close up of a Bluestreak Cleaner Wrasse

Credit: François Libert

With the exception of the top and lower segments, which are blue, this band often occupies the majority of the tail. With the exception of a light band along the lower, upper, and rear caudal rays, young wrasses can occasionally be entirely black. Juvenile and mature Cleaner Wrasses have different hues. In accordance with their emotional state, they are also known to alter their hue.

Diet

The Cleaner Wrasses welcome guests by moving their rears up and down in a dance-like gesture when they approach the cleaning stations. Bluestreak Cleaner Wrasses clean host fish so they may eat the ectoparasites. Because they have a lateral stripe running the length of their bodies and because of the way they swim, other fish may identify them as cleaner fish. Then they provide access to their body surface, gills, and occasionally mouth.

The degree to which the Bluestreak Cleaner Wrasse relies on its customers’ ectoparasites as its main food supply varies according to the locale. The Bluestreak Cleaner Wrasse feeds on corals rather than fish in tidal habitats such as the Great Barrier Reef.

Habitat

The Bluestreak Cleaner Wrasse inhabits coral reefs in the tropics, from the Red Sea and the Indian Ocean all the way to the western Pacific. They are also spread out into Papua New Guinea, Japan, Fiji, and French Polynesia.

Bluestreak Cleaner Wrasse helps clean a Moray Eel
Bluestreak Cleaner Wrasse helps clean a Moray Eel

Credit: Patxi Vidal Landaribar

They typically create cleaning stations, which are visible locations around the reef, such as outcropping rocks, where other fish may go to obtain alleviation from parasites. Bluestreak Cleaner Wrasse established cleaning stations as means to secure an adequate food source. The newcomer Bluestreak Cleaner Wrasse will typically be chased out of the current Cleaner Wrasse’s habitat. An encroachment is a rivalry for scarce resources.

Reproduction

Bluestreak Cleaner Wrasse is a hermaphrodite species. Wrasses use an external fertilization technique where the female releases her eggs into the water. Sunset is often when animals breed. Large males defend reef territory and draw several females there, frequently by engaging in a stunning courtship ritual. Within these boundaries, females reside and reproduce with males. 

Planktonic larvae are formed from fertilized eggs and float freely in ocean currents. The most dominating female will assume the position of the territorial male and turn into a male within the next 20-24 hours if he departs or passes away. She takes over the area and mates with the other females.

Threats

The Bluestreak Cleaner Wrasse is on the least concern list among endangered species. It doesn’t have a special protection status among all watchdog organizations committed to raising awareness for endangered species. 

Juvenile Bluestreak Cleaner Wrasse noted from its jet-black body
Juvenile Bluestreak Cleaner Wrasse noted from its jet-black body

Credit: François Libert

While aggressive predators like moray eels and barracudas can easily attack the Bluestreak Cleaner Wrasse, they most often will put their aggression to the side. The threat that Bluestreak Cleaner Wrasse faces is virtually non-existent. The benefits that these fish provide for the ecosystem and its participants are more valuable than a simple meal. 

Facts about the Cleaner Wrasse

  • The first fish to ever be seen passing the mirror test were Cleaner Wrasses.
  • Cleaner Wrasse forms symbiotic relationships with most other species of fish.
  • The participants of the cleaning relationship of Cleaner Wrasse are known as “clients”.
  • Cleaner Wrasse is highly territorial of their cleaning stations.
  • Cleaner Wrasse can switch from male to female and vice versa.


FAQs

What fish does the Cleaner Wrasse clean?

The Balaenopteridae, Chondrichthyans, Homaridae, Octopodidae, Dermochelyidae, and even highly aggressive predators such as barracudas are documented to be cleaned by the Bluestreak Cleaner Wrasse.

Is Cleaner Wrasse friendly?

As a species, the Cleaner Wrasse is the least aggressive; it can be argued that they are particularly friendly as means to attract potential fish, which usually means another food source is secured.

Do Cleaner Wrasse clean sharks’ teeth?

All those little fish feed on the parasites that live on sharks’ bodies, which helps the shark. Additionally, the cleaner wrasse will make its way inside the shark’s mouth, where it will consume any scraps that the shark hasn’t previously ingested.

Are Cleaner Wrasse self-aware?

Amazingly, a recent study now contends that the cleaner wrasse, a small tropical coral fish, is the first animal to be capable of recognizing itself. To determine if an animal is capable of visual self-recognition and, therefore, self-awareness, scientists have traditionally utilized a mirror test.