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Yellowhead Jawfish Breeding | A Complete Guide |

If you enjoy watching underwater excavators and would like social ones in your tank, Yellowhead jawfish can be a perfect choice for you! They work all day tirelessly long to maintain their home and rarely bother with their tank mates. Although they are small, they are well known for their personality. They are also easy to breed in captivity.

This article will guide you through the yellowhead jawfish breeding with tips and tricks to get them on the right track.

Yellowhead Jawfish Breeding

What is yellowhead jawfish, and how do they reproduce?

Yellowhead jawfish (Opistognathus aurifrons) are found in the Western Atlantic Ocean from Florida to Brazil.

They inhabit shallow reefs and prefer areas with a sandy substrate where they can bury themselves.

The Yellowhead jawfish is a small-sized fish with a yellow head and brown body. The male yellowhead jawfish are usually larger than the females and can reach a size of up to 4 inches (10.16 cm).

The Yellowhead jawfish are mouthbrooders, meaning that the male incubates the eggs in his mouth until they hatch. The fries are then released into the water column, where they fend for themselves.

While most fish release their eggs and larvae into the open water, yellowhead jawfish keep their eggs in their mouths until they are fully developed and hatch.

This behavior helps to protect the fry from predators and gives them a higher chance of survival.

How many eggs do yellowhead jawfish lay?

The number of eggs that a yellowhead jawfish lays depends on the size of the female. A large female yellowhead jawfish can lay up to 200 eggs, while a small female may only lay 50 to 100 eggs.

When do yellowhead jawfish breed?

Yellowhead jawfish breed throughout the year, but the peak breeding season is from May to August.

How long does it take for yellowhead jawfish eggs to hatch?

The incubation period for jawfish eggs is about 7 to 9 days. The male jawfish releases the fry once they hatch. This often happens after the sunset.

Tip: According to Blenny Watcher, Yellowhead jawfish release their eggs “30 minutes after the sunset”. Some may say it will happen early in the morning, but this is just a misconception.

Do yellowhead jawfish show prenatal care after the eggs hatch?

Yes. Yellowhead jawfish are prenatal mouth brooders, which means the fry develops and hatch inside the male’s mouth. The fry is then released into the water column, where they fend for themselves.

Yellowhead jawfish male and female identification

Usually, most jawfish species exhibit color variations during breeding. Unfortunately, yellowhead jawfish do not display this behavior.

So, it isn’t easy to distinguish male from female as both sexes look alike, even during the spawning season.

The only way to decide the sex of yellowhead jawfish is by observing their breeding behavior. You will have to wait until your fish get ready to spawn.

Once they are ready to breed, the male will leave its den and arch its body. Then it will spread all the fins and open its mouth as wide as possible. This is to show the female its mouth-brooding prowess.

If the female is impressed, she will allow the male to chase her into his den. There, the pair will spawn, and the female will lay her eggs inside the male’s mouth.

While you observe this courtship behavior, you will miss one spawning session already. However, you can separate the pair to another tank and wait for another spawning session, which will come sooner.

How to set up a yellowhead jawfish breeding tank?

The first thing you need to do is to set up a separate breeding tank for your yellowhead jawfish. This is to make sure that the fries have a place to grow and develop without being eaten by other fish.

The breeding tank of yellowhead jawfish should be at least 30 gallons (136.383 liters) in size. It should also have a deep sandy substrate and plenty of rocks and coral for the jawfish to hide in.

The sand bed of their tank should be at least 5 to 7 inches deep so that your jawfish can bury themselves.

The fish tank should also have a tight-fitting lid to stop the jawfish from jumping out. Jawfish are known to be jumpers, so a lid is a must.

The water temperature in the jawfish breeding tank should be between 75 and 82 degrees Fahrenheit (24 to 28 degrees Celsius).

The pH should be between 8.1 and 8.4, and the water should be well-aerated with a powerhead or air pump.

The carbonate hardness should stay between 8 and 12° dKH, and the specific gravity should be at 1.020-1.023.

So, basically, this means that the breeding tank should have the same conditions as the main tank.

Additionally, you can keep a refugium (another tank) for the fries to grow up. Or else, you can move the parents into the main tank once you get the offspring in the breeding tank.

Yellowhead jawfish breeding

Move breeding pair in to separate tank

The first thing you ought to do is move the breeding pair into the breeding tank. You may already have missed the spawning, but don’t be discouraged as these fish spawn all year along. 

Important: If you see the male fish is already keeping eggs in his mouth, DO NOT move your fish into the breeding tank unless it is an already established tank. (This means that your jawfishes should already have built burrows for them to hide in.)

Otherwise, your mouthbrooding fish will not be able to burrow itself in since he can not build a new burrow as he is holding eggs.

Use species only tank

Another easier way to breed yellowhead jawfish is to keep a species-only tank. As it is difficult to identify the sex of these fish, many choose to keep a group of fish to ensure both male and female fish are present in the tank.

The magic number is six fish in the tank. However, the tank should be large enough to provide separate territory for each fish. Otherwise, you will have one big mess in the tank. 

If you successfully get a breeding pair, you can move them into the breeding tank. If not, you can leave them in the main tank and wait for them to spawn. 

Egg laying process

Once the female jawfish is ready to lay her eggs, she will arch her body and release them into the male’s mouth. The male jawfish will then fertilize the eggs and hold them in his mouth for about 7 to 9 days. 

The male jawfish will not eat anything during this time. He will just stay in his burrow and fan the eggs to aerate them. He will also change the water by spitting the water out and taking in new water. 

Hatching the eggs

After 7 to 9 days, the fry will be ready to be released. The male will then open his mouth and release the fry into the water column.

The fries are very tiny and are not able to swim well. They will usually just sink to the bottom of the tank. 

Tip: Just one to two days before releasing the fries, the mouthbrooding fish will routinely pull some rocks and debris over his hole for protection.

Although jawfishes usually cap their holes for the night, the mouthbrooding fish who is ready to release his fry will not do so.

Tip: If you want to observe your fish release its eggs, make sure that the lights are dim. Otherwise, your fish will get stressed and not continue the process.

Once the fries are released, they are on their own. The parents will not care for them. In fact, if you see the parents eating their own fry, then it is best to remove them from the tank. 

Yellowhead jawfish fry care

Yellowhead fries are about 4mm in size. They will triple their size within about two weeks. However, they are still very small and cannot compete with other fish for food. 

Unlike other saltwater burrowing fish species, caring for yellowhead jawfish is relatively easy. Like other fish, they are not demanding and will do fine in most aquariums.

It is best to remove the fries into the refugium or remove the parent fish from the breeding tank. Otherwise, you will not see many fries survive to adulthood. 

The fry will hide in the rocks and debris for the first few days. They will slowly start to come out and swim around as they grow bigger.

You can begin to feed them live baby brine shrimp, enriched rotifers, or copepods once they are big enough to eat them.

How long does it take for a yellowhead jawfish fry to grow up?

Yellowhead jawfish fry takes about one year to grow up. Once yellowhead jawfish fries reach maturity, they will start to form pairs and breed. 

Yellowhead jawfish lifespan

The average yellowhead jawfish lifespan is about five years. However, some yellowhead jawfish have been known to live up to 8 years in captivity.

Yellowhead jawfish tank size

The minimum tank size for a yellowhead jawfish is 30 gallons. Of course, that assumes you only intend to retain ONE jawfish. If you want to keep several fish, you will have to increase the tank size accordingly. 

A 40-gallon tank can house a pair of yellowhead jawfish. If you want to keep more than a pair, you will need to increase the tank size by 10 gallons or more for each additional fish. 

Tank set up and water quality

Since yellowhead jawfish are used to living in tropical Atlantic waters, it is expected to provide them the same water conditions in captivity

The main tank setup mimics the breeding tank setup we covered before. Basically, these fish require temperate saltwater conditions with a deep sand bed to build their burrows. 

As for the water quality, these fish are pretty tolerant to most water parameters. They can live in a wide range of temperatures (72 to 82 degrees Fahrenheit), salinity (1.020 to 1.025 specific gravity), and pH (8.1 to 8.4). 

Of course, it is always best to provide them with the optimal water conditions for their long-term health and well-being. 

Feeding yellowhead jawfish

These fish are known to feed on small crustaceans, zooplankton, and other tiny marine creatures in the wild. 

They will readily accept most live, frozen and freeze-dried foods in captivity. You can feed your fish with live baby brine shrimp, Mysis shrimp, blood worms, black worms, and similar foods. 

However, you will have to feed them at their burrow entrance. Otherwise, they will be too shy to come out and compete with other fish for food. 

To make things easier, you can use a turkey baster or a small tube to target feed your fish. 

Yellowhead jawfish tankmates

These fish are relatively peaceful and can be kept with the most peaceful community fish. However, they are known to be aggressive towards their own kind.

So, it is best to keep them as a single fish or in a mated pair. If you intend to keep a group of yellowhead jawfish, you will have to increase the tank size accordingly.

Some good tankmates for yellowhead jawfish include:

  • Clownfish
  • Cardinalfish
  • Gobies
  • Blennies
  • Firefish 
  • Pipefish
  • Dottybacks
  • etc.

As you can see, many different kinds of fish can get along with yellowhead jawfish. Just be sure to avoid aggressive fish that may bully or harass these peaceful bottom dwellers. 

Further, avoid adding small crustaceans as these fish tend to nip at them and eat them.

You can even house these fish with other jawfish species if your tank is big enough. Just be sure to provide your jawfish with plenty of hiding places and sand beds so they can establish their own territories. 

Important: If you intend to breed yellowhead jawfish, it is better to keep a species-only tank. Otherwise, the fry will likely be eaten by other tankmates.


Yellowhead jawfish breeding is not straightforward. But it is possible to breed these fish in captivity.

The main key is to provide them with the right tank setup and water conditions. Also, be sure to feed them live foods at their burrow entrance.

If you can do all that, you will likely be successful in breeding these exciting fish. 

Credit to : AquariumKids
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About Dr.Chamika

Hello, I'm Dr. Chamika. I am a Researcher in Water quality, Aquatic organisms, and Environmental chemistry. I am a passionate fish keeper, with10 years of experience. My mission is to help other aquarists experience the joy of fish keeping.