News / Species Spotlight / Highly Underrated Fish - One Spot Rabbitfish (10/01/14)

Highly Underrated Fish - One Spot Rabbitfish

In The Wild

Siganus unimaculatus is a very common fish all over the tropical Pacific. As juveniles they form schools up to several hundred individuals. These schools break down into pairs as the fish segue into adulthood. They are usually found in less than 90 feet of water, most frequently on the shallow end of that range.

They have a maximum size of nearly 8 inches, which is one of the reasons they are also harvested commercially as a food fish. They are primarily herbivorous though a large quantity of small inverts are likely to be ingested as well.

S. unimaculatus is a "venomous" fish; its dorsal spines have a weak venom that makes it a less desirable prey item for larger carnivores. The venom is not unlike that utilized by panfish and catfish. These fish have a very short population doubling time, making them very resilient as a population.

In The Aquarium

Siganus unimaculatus is also known as the One Spot Rabbitfish, the One Spot Foxface and the Blotched Foxface. They are a very common fish in the south Pacific and are one of the hobby's best algae grazers. Like most "Rabbitfish" they are so named because of their propensity for vegetation in their diets, as well as a superficial likeness in appearance to rabbits.

For hobbyists looking for grazers, this family has no equal in that department. They are aggressive consumers of many nuisance algae including hair algae, most forms of caulerpa and occasionally even bubble algae. Because of this, a large amount of vegetable matter should be included in their diet; we like to feed them a variety of algae and occasionally nori. They always take pellets within a few days of arriving here.

Much is made of their being venomous. This venom is very weak, and a tiny bit of common sense can prevent anyone from ever having to experience it's burn (don't pick them up without gloves). This is a very timid fish, and they use their spines only in self defense. Having one in your tank will not prevent you from reaching in to do maintenance.

Small (under 3 inches) One Spot Rabbits can be added in small groups. To avoid aggression, larger specimens should be added singly or in pairs. Adding any Rabbit to a system with established fish (especially Angels and Tangs) is ok, but expect the Rabbit to be shy for a little while. unimaculatus
Scott W. Michael, Reef Aquarium Fishes, 1st ed. (T.F.H. Publications Inc, New Jersey, 2005).