Humphead Wrasses: A Threatened Reef Fish
The Humphead, Maori or Napoleon (to mention but a few of its many names) wrasse,Cheilinus undulatus, is the largest member of the family Labridae and widely distributed across the reefs of the Indo-Pacific.
It is listed as Endangered on the IUCN Red List and included in CITES Appendix II in 2004. This species was the first reef fish used as food to be listed on the Convention on International Trade in Endangered species (CITES). The species is conservation dependent.
It is now clear, based on the results of studies, surveys, and many different anecdotal accounts, that the Humphead wrasse cannot withstand anything other than light levels of fishing pressure. It is susceptible to over-exploitation due to its life history, that involves late sexual maturation (sometimes up to 5 years and 35-50 cm total length), long life (over 30 years) and sex reversal from female to male. It appears to be highly vulnerable to overfishing, especially where an export trade has developed, or where night-fishing occurs using SCUBA gear (dive tanks). Despite its widespread distribution, adults of the species are nowhere particularly common, except in a few very well and long-protected areas. Indeed, as far as we can tell, it is becoming increasingly uncommon. Illegal capture of undersize, juvenile fish often occurs, often using cyanide as the fishing method because the species is otherwise difficult to capture.
Historically the Humphead wrasse was prized for its flavour and texture. Considered in some areas to be a 'stately' or 'royal' fish, it is, or once was, highly valued in many cultures and used only for special occasions or exclusively available to highly ranked members of Society. More recently (1990s onwards) it has come to form an important part of the live reef food fish trade (LRFFT) centred in Southeast Asia, at times commanding over US$500 per kg at retail (e.g. in Beijing in 2015 at a luxury hotel). It is one of the two most highly priced fishes in this international trade.
Traditionally, the wrasse was fished by hook and line, hand spear (more recently by speargun using SCUBA, or diving tanks) or by trap, depending on fish size. Larger fish may sometimes be taken at night from their resting places where they are easy targets for SCUBA divers. To catch them alive for the LRFFT, cyanide is frequently used in some areas for it is not an easy fish to catch. Indeed, most smaller, juvenile, fish are almost exclusively taken with cyanide. The use of this poison as a fishing method is widely despised for it is known to kill living coral, itself an important habitat for this, as well as other, reef fish and invertebrate species. Traders of live fish sometimes supply fishers with cyanide. Although cyanide is a poison and will quickly knock out any fish exposed to cyanide solution, if the target fish is rapidly removed to fresh water, it will survive. However, the cyanide can kill corals on repeated use and also causes much bycatch death among those animals exposed to the poison but not removed.
Now protected in many countries, most legal trade in the species is out of Indonesia and into Hong Kong where some fish are consumed and many transshipped to Mainland China. Most Humphead wrasse in this international trade are less than 50 cm total length, and most are juveniles. Thus, trade in this species is almost exclusively one of small large juveniles, a pattern that will doubtless exacerbate the threatened status of this species because its populations are poorly managed. The problem with juvenile fisheries is that insufficient adults will remain in the future to replenish exploited populations (imagine removing all the children from our cities, where will the next generation come from?). The Humphead wrasse cannot yet be hatchery-reared at commercial levels, so all fish in trade are wild-caught.
Due to documented declines, the Humphead wrasse was listed as vulnerable in the IUCN Red List of Threatened Species in 1996 and later upgraded to endangered (2004). The status of this species as a luxury food means that its market value is likely to increase as it becomes less readily available from the wild due to overfishing, thereby encouraging continued exploitation even as populations decline. Such has been the concern for illegal trade in this species that a Decision by the CITES Secretariat was issued in 2010 to look more closely at the legality of its international trade.