News / Species Spotlight / Hawaiis Unique Marine Fish Fauna (01/24/18)

Hawaiis Unique Marine Fish Fauna

Hawaiis Unique Marine Fish Fauna
In late October of this year, the First Circuit Court of Hawaii issued a ruling which effectively halted the collection of aquarium fishes from Hawaiian waters. Though this fishery has long been held up as being among the most highly sustainable and well-regulated in the industry, opponents successfully claimed that it violated existing law, as there had not been, in their eyes, an adequate study conducted on the matter by Hawaiis Department of Land & Natural Resources. Since this is stipulated by Hawaiian law, the courts have taken the drastic step of stopping all aquarium fish collection until such a study can be performed.

Sadly, this means that the beautiful fishes of Hawaii are off limits for the foreseeable future. It may be years before this issue is put to rest and exports can resume, and, if opponents have their way, exportation may never again be allowed. So while we wait for this issue to be resolved, lets take a quick look at some of the species which will no longer be available.

Yellow Tang (Zebrasoma flavescens)
Arguably the single most iconic of Hawaiis marine fishes, this fish has been a lightening rod for controversy among those conservationists who insist its numbers have been reduced by aquarium collection. However, surveys from the areas marine protected areas have generally countered this notion, showing a robust population. Countless millions of this tang exist throughout Hawaii, forming vast shoals that scour the shallow reefs of algae. Thanks to its abundance and beauty, Z. flavescens has become a staple in the marine aquarium hobby and was Hawaiis number one piscine export.

Though it is most closely associated with Hawaii, the species is not actually endemic here. The Yellow Tang has a peculiar distribution, with large populations at both Hawaii and the Mariana and Ogasawara Islands. It also occurs semi-regularly in Japan and as far west as the Northern Philippines. The specimens in this latter location are probably not permanent residents, but, rather, represent isolated juveniles that have drifted over from the waters around Guam. These do sometimes get collected, so Z. flavescens will likely be available on rare occasion, likely at a significant cost given its sudden rarity.

A recommendable substitute is the Scopas Tang (Z. scopas). This fish is the sister species of its yellow cousin and occurs in all the waters of the Indo-Pacific where Z. flavescens is absent. On occasion, xanthic specimens of Z. scopas are found, and these false Yellow Tangs do find their way into aquarium exports. The easiest way to tell them apart from a true Z. flavescens is to look for the fine patterning present around the head and sides of Z. scopas even the yellow ones will have this.

Flame Wrasse (Cirrhilabrus jordani)
Its painful to say that there will be no more Flame Wrasses available from now on. This is a true Hawaiian endemic, found nowhere else. But there are several suitable replacements if youre looking for a bright red wrasse. Take, for instance, the Magma Fairy Wrasse (Cirrhilabrus sp.), which was discovered last year in the Northern Philippines. It belongs to the same species group as C. jordani and is seemingly its equivalent in these waters (and likely to the east in the Mariana Islands). The two share a number of similarities in their color patterns, both being primarily red fishes with a bit of yellow. And, since both of these fishes originate from fairly deep reefs, they are similarly priced. For an inexpensive option, consider the Redfin Fairy Wrasse (C. rubripinnis), another product of the Philippines. It abounds in shallow niches, swimming alongside gigantic swarms of flasherwrasses and sailfin anthias.

Bandit Angelfish (Apolemichthys arcuatus)
This stately black and white beauty is another casualty of the Hawaiian ban. It occurs only along the deeper reefs here, and is said to be an especially easy fish to collect from the wild, practically swimming into hand nets when approached underwater by collectors. Because of this, collectors have typically focused on collecting only the smaller individuals, leaving the adults to continually repopulate the region with new generations of juveniles. Will banning the collection of this species ultimately have any impact on its numbers, especially given how few individuals were actually exported? Unfortunately, there really is no substitute for this one-of-a-kind angelfish. One of its closest relative is thought to be Colins Angelfish (Centropyge colini), and, though it differs dramatically in color, the two are similar in disposition and husbandry.

Potters Angelfish (Centropyge potteri)
This is another standout pomacanthid that will no longer be available. The Potters Angelfish is a connoisseurs species, sought after by those who know of its considerable beauty, but generally unknown to casual aquarists. In many ways, its like a more beautiful version of the familiar Coral Beauty (C. bispinosa), having a similar blue and orange arrangement, with thin vertical bars running throughout the body. Their patterns are essentially reversed, with C. potteri having an orange face and back and C. bispinosa being orange only along its midbody. Since their care is otherwise identical, they can be substituted easily enough, but, in our hearts, the Coral Beauty, lovely though it may be, can never truly replace the majesty of the Potters Angelfish.

And there are many more examples we can list, all of which will be missed. Whether it be the subtle elegance of the Hawaiian Humbug Damselfish (Dascyllus albisella) or the comical Hawaiian White Spotted Toby (Canthigaster jactator) or the efficacious Kole Tang (Ctenochaetus strigosus). Not to mention the deepwater rarities, like the Sunrise Hogfish (Bodianus sanguineus) or the Yellow Anthias (Odontanthias fuscipennis) or the inimitable Personatus Angelfish (Genicanthus personatus). They will all be missed. Hopefully, Hawaii will once again be able to provide aquarists around the world with its beautiful and sustainably harvested fishes.