The Longnose Hawkfish (Oxycirrhites typus)

Author: Bob Fenner

A popular marine staple, the longnose hawkfish makes an excellent addition to a peaceful setup with plenty of places for it to perch and look out over its aquatic domain.

Good News, Hobbysists!

The longnose hawkfish (Oxycirrhites typus) had a reputation for being both expensive and hard to find, but now it is relatively affordable and easy to obtain. That is great news for hobbyists; like all hawkfish, this species is bright, intelligent, disease-resistant, and a real character. It can even be frisky at times! Be forewarned, however; the longnose is meant for larger reefs and peaceful fish-only systems—it is not meant for every tank.

Hawkfish Natural History

Hawkfishes are distributed principally in the Indo-Pacific, with two species originating in the tropical western and eastern Atlantic Ocean. Most species are found in shallow water, with some being found at depths of up to a few hundred feet.

The longnose hawkfish itself is found widely throughout the tropical Indo-Pacific, the Red Sea, off the coast of eastern Africa to southern Japan, Noumea over to the eastern Pacific, and the lower third of the Sea of Cortez from northern Colombia down to the Galapagos. The fish is not commonly found throughout its range, and at times one has to dive deep outer reef slopes and search about large gorgonians and black coral stands to find it.

Appearance

Superficially, hawkfishes resemble rockfish, scorpionfish, and lionfish, but they lack the prominent head spines found on members of the scorpionfish family. Hawkfishes have a continuous, 10-spine dorsal fin that includes both hard and soft dorsal rays, some of which often have cirri (which look like small pom-poms) at their tips. The pectoral fins are distinctive with elongated, unbranched lower rays. Their tail fins are truncate (squared off). Longnose hawkfish reach about 5 inches in total length.

If you collect your own fish, it is important to know that all members of the hawkfish family lack swim bladders. This means they can be rapidly decompressed after capture. That is a real bonus because it allows you to avoid waiting out in bouncy seas for your catch to decompress, especially if your catch is from deeper waters and takes considerable time to adapt.

Environment

Longnose hawkfish are almost always found skirting around lacey, fan-shaped, stinging-celled animals, particularly sea fans and black corals. I recommend that you provide similarly shaped structure, whether it is alive, a skeleton, or fake, though this species is highly adaptable and will learn to live in caves, overhangs, and on other perches in your system.

O. typus requires plenty of room—a bare minimum of 60 gallons if the tank is not crowded, but it is much better to have a system of 100 gallons. Other than the need for space and its preference for perches, this species really has no other special considerations. It just needs a standard marine aquarium setup along with regular maintenance.

In fact, despite their reputation for being secretive at times and the fact that they are nocturnal and possess large eyes, longnose hawkfish have been observed adapting to well-lit aquarium conditions. Though this species can be found as deep as 300 feet, most are collected from their minimum depth of about 30 feet or so in Micronesia.

Territoriality

Longnose hawkfish get along fine with other species as long as their tankmates are larger than bite sized, though they can sometimes become territorial after being in the same system for a long time. Rearranging the decor or adding or removing parts of their habitat alleviates this problem. They may chase other fishes but rarely do any damage.

Don’t Mix Hawkfishes

But in general, it is not a good idea to mix hawkfishes (of the same or different species) due to their territorial nature. To put it bluntly, unless you have a system that is huge—at least several hundreds of gallons—one hawk to a tank is the rule. Also, add it later on in the stocking lineup to reduce territorial tension.

Reef Tank Considerations

Be careful if you plan to keep your hawkfish in a reef system, as most have relatively large jaws and sharp teeth that are ideal for capturing crustaceans. As far as hawkfish species go, the longnose, with its much smaller mouth, is probably the best candidate for reef tanks, though it can and will eat small crustaceans and worms. In fact, small molting hermit crabs and feather duster worms have been consumed in captivity by O. typus.

The longnose, like most hawkfish, will generally leave almost all stinging-celled life alone, but it can become a meal if placed in a system with very powerful stinging animals like Catalaphyllia corals or sea anemones. Also, be aware that other cnidarians can be irritated by the hawkfish’s settling behavior, which can cause polyps to close up. Try to have a larger system with carefully chosen corals.

Tankmates

Some good tankmate choices include dwarf angels (as long as they’re not too small), dottybacks, most damselfishes, larger gobies and blennies, midsized wrasses, and any motile invertebrates that are not mouth-sized crustaceans and worms. To reiterate, hawkfish should be the last specimens added to a tank due to their territorial nature.

Foods and Feeding

Longnoses, like most other hawkfish, spend most of their time perched on a rock, sea fan, or piece of coral, waiting to make a short, fast rush at a food item. Their conical teeth are modified for grasping benthic and free-swimming crustaceans (their principal diet in the wild). In captivity, most specimens can readily learn to accept live, fresh, frozen/defrosted, and even some prepared foods readily with only brief training.

Disease

Hawkfish are typically quite healthy and have a low parasite load. In fact, other fishes in a system will typically show symptoms of disease and succumb before a resident hawkfish does. They are not particularly sensitive to medications or treatments. Of course, quarantine and a prophylactic dip are suggested.

Reproduction

The longnose hawkfish is known to lay demersal eggs (eggs that sink to the bottom) (Randall, 1981). Takeshita (1975) describes a courtship dance that occurred in the early evenings with a pair in captivity. He describes males as being smaller and more colorful, with black margins on the pelvic and caudal fins. All hawkfish that have been studied are protogynous, synchronous hermaphrodites—they start life as females and eventually turn into males. Some species of hawkfish form harems, but longnoses remain in monogamous pairs.

In captivity, pairs have formed and spawned (laying demersal eggs), but as of this writing, the young have not been raised to maturity. If you’re interested in trying to spawn them, it is advised to introduce two animals of about the same size simultaneously and then watch them for overly antagonistic behavior.

A Hawkfish Home

Do you have room for a colorful, comical, aquatic acrobat in your otherwise peaceful marine system? Assuming you don’t have small crustaceans, a longnose hawkfish might be perfect for you. Like all members of its family, the longnose is not a conspicuous, out-and-about tropical, but it is always an interesting conversation piece.

See the full article on TFH Digital http://www.tfhdigital.com/tfh/201203#pg89