Yellowhead Jawfish

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The species Opistognathus aurifrons is known under several different names in English, including Yellowhead Jawfish, Yellow-head Jawfish, Yellow-headed Jawfish, Pearly Jawfish, and Yellow Headed Pearly Jawfish.   

Opistognathus aurifrons has not been evaluated for the IUCN Red List of Threatened Species.

Geographical range, habitat and habits

The Yellowhead Jawfish inhabits the Western Central Atlantic. Its native range stretches from Florida, USA down to the northern parts of South America. This is a reef associated species that live inside burrows made of crushed coral and sand. It is typically found in sandy and rubble-strewn reef environments. These fishes enter the burrow tail first and you can often see their head stick up from the whole while the rest of the body remains hidden.

When the fish is not hiding, you can see it hover vertically in close vicinity to its burrow, often straight above it. If anything frightens it, it will instantly dart back to its protective burrow tail first. This fish will not swim around much, because it wants to stay close to its burrow at all times. In the wild, you can find large colonies of Yellowhead Jawfish.  

The depth range for the Yellowhead Jawfish is 3-40 meters / 10-131 feet.   

Size and appearance

The largest scientifically measured Yellowhead Jawfish was 10.0 cm / 3.9 in.

The body is of a bluish gray shade and decorated with an abundance of pale blue dots. The head, nape and anterior section of the dorsal fin are yellow. On the chin, you can se a pair of black dots.  

Yellowhead Jawfish care

If you wish to keep Yellowhead Jawfish, you need an aquarium of at least 30 gallons / 115 litres. The aquariums should ideally be at least 3 feet / 90 cm in length. A secure lid is strongly recommended since this fish is an agile jumper, especially if frightened.

The bottom of the aquarium should be covered in a deep (at least 3 in/7.5 cm) layer of sand since the Yellowhead Jawfish needs to dig out a burrow. Ideally use various grades of sand (not only soft sand) and include crushed corals. Also use large amounts of rock for the set up to mimic the natural environment of this species. Various size rocks among the soft substrate can be necessary to help reinforce the burrows and rockpiles will be highly appreciated.

All heavy objects must be placed directly on the glass; otherwise they might fall when the fish is digging.

The Yellowhead Jawfish is generally a peaceful species that can be kept with other peaceful species of similar size in the community aquarium. Aggressive species should be avoided and it is also safest to avoid other burrowing fishes that may bully the docile jawfish. As mentioned above, you can find large colonies of Yellowhead Jawfish in the wild and you can keep a colony if your aquarium is big enough. An entire colony of Yellowhead Jawfish hovering above their burrows is a fascinating sight. Sticking to one species of jawfish is safer than trying to combine several species.

The Yellowhead Jawfish may nip at and even eat small crustaceans in the aquarium.  
The recommended water temperature when keeping Yellowhead Jawfish is 75-82° F / 25-28° C. The pH-value should be in the 8.1-8.4 range, the carbonate hardness at 8 - 12° dKH, and the specific gravity at 1.020-1.023.

Feeding Yellowhead Jawfish

The Yellowhead Jawfish feeds chiefly on zooplankton and detritus in the wild. Since it is primarily a carnivore, it needs to be provided with meaty foods in the aquarium. You can for instance give it brine shrimp, mysis shrimp, bloodworms and small pieces of clam flesh. It can be trained to accept fresh, frozen and dried food in addition to live food. To make sure it gets everything they need, it is recommended to feed it high-quality flake food (with vitamins) as well. Most specimens will start eating dry food eventually but it can take some time for the fish to realise that it is actually food.

The shy Yellowhead Jawfish doesn’t like to venture far from its burrow, especially not when newly introduced to a new aquarium, and it is therefore advisable to place the food near the opening of the burrow. When it feels safer in the aquarium it will dare to swim further and further away from its home to find food.

Breeding Yellowhead Jawfish

The Yellowhead Jawfish is an egg-laying species where the male fish broods the offspring inside his mouth. This is called paternal mouth-brooding. The eggs will hatch inside his mouth and the offspring will not be released until they are large enough to be free swimming.

During spawning, the male will court the female by swimming in an arched position with his fins spread towards her.

Several other species of jawfish changes colour during the period period, but this is not the case for the Yellowhead Jawfish.

The Yellowhead Jawfish has been reared in captivity.