# Asian sheephead wrasse

The Asian sheephead wrasse (Bodianus reticulatus), also known as kobudai in Japan, is one of the largest species of wrasse. Native to the western Pacific Ocean, it inhabits rocky reef areas and prefers temperate waters around the Korean Peninsula, China, Japan, and the Ogasawara Islands. It can reach 100 cm (39 in) in total length, and the greatest weight recorded is 14.7 kg (32 lb).

## Taxonomy

The Asian sheephead wrasse, as the common name indicates, is a wrasse, and thus is in the family Labridae. It has long been placed in the genus Semicossyphus, along with the California and goldspot sheephead wrasses, but a 2016 molecular phylogenetics study suggested that it (along with its two congeners in Semicossyphus) be moved to Bodianus, as Semicossyphus was nested deep within Bodianus. The phylogenetic placement of Semicossyphus was supported by subsequent studies as well.

## Description

The Asian sheephead wrasse is one of the largest labrid species found in the waters of the western Pacific, reaching a weight of around 14.7 kg (32 lb) and a length of 100 cm (39 in). The body is globiform and bulky, and males are typically larger than females. The mouth is terminal, consistent with the fact that this fish is usually present in the middle of the water column, and prefer to eat prey directly in front of them or beneath them. This fish has hard tooth-like structures present in the mouth, which are excellent for crushing crustaceans. The caudal fin is truncate.
The fish is most known for the development of its bulbous forehead; however, this is prominent only in (adult) males, and juveniles lack this feature entirely. However, the juveniles do have black areas on certain fins; they are eventually lost in adults, and give way to the dominating pink-gray color of adults. So, unlike many other wrasses, the Asian sheephead wrasse is not particularly colorful.
Like many other wrasses, the Asian sheephead wrasse is sequential hermaphroditic species. Specifically, they are protogynous, meaning that fishes of this species are always born female and only change sex when they grow older (although there is no definite age when this occurs) and reach a critical body size; the sex change does not always happen, and the reverse change is not possible. After the transition, the fish gains a bulbous forehead.

## Biology
### Reproduction

As mentioned above, adult females of this species are able to change into males when they reach a critical body size; after the transition, the fish gains a bulbous forehead, and also starts exhibiting aggressive behavior. Post-transitioned males possess some left-over characteristics of females, including some ovariform gonads.
Males and females reproduce by practicing spawning, which usually occurs in warmer waters; prior to mating, males and females engage in courtship. It has been observed that one large male tends to mate with multiple smaller females at the same time, indicating a polygynous mating system.

### Age and growth

This fish is able to live up to forty to fifty years. At age zero, immature females are around 1 cm (0.39 in) in length, reaching around 40 cm (16 in) at the age of fifteen years. Mature males are around 40 cm (16 in) to 60 cm (24 in) and can spend the remaining portion of their lives that size.

### Diet

This fish mostly consumes marine invertebrates such as mollusks, crabs, and sea urchins, but also takes vertebrates like small fish. In eating sea urchins, the Asian sheephead wrasse plays an important role in their population control, and thus is crucial in maintaining healthy marine habitats.

## Human interaction

The sheephead wrasse gained media attention when the sex change was caught on camera by the BBC Earth crew while filming in the waters near Sado Island, Japan. In 2017, it was shown on the Blue Planet II episode "One Ocean".
According to Great Big Story, Japanese diver Hiroyuki Arakawa had a 30-year relationship with an Asian sheephead wrasse, which he named "Yuriko", in Japan's Tateyama Bay, where he was the caretaker for an underwater Shinto shrine. He called Yuriko by hitting a bell on the underwater shrine.
In Japan, this species is considered edible, and it is valued for its sweet, shellfish-like taste.

## Conservation status

The Asian sheephead wrasse is vulnerable to anthropogenic impacts and has suffered declines; directly ones include overfishing (and unsustainable fishing practices such as bottom trawling), pollution and habitat loss and degradation, but there are many other indirect anthropogenic factors. Despite this, the IUCN lists this fish as Data Deficient, which means that it views the proper conservation status of this species to be undetermined due to a lack of data.

## Gallery

* Juvenile
* Attended by a bluestreak cleaner wrasse