Do you want to know the sex of the ornamental goldfish (Carassius auratus)? You may want to know this for breeding fish, or to have the fish name match their gender. Fortunately, you can identify the sex of an ornamental goldfish by observing the fish's body and behavior.
Step
Part 1 of 3: Identifying the Female
Step 1. Watch for fish with a more rounded and stockier body shape
Female goldfish generally have a rounder and stockier body than male goldfish of the same age and species.
- Female ornamental gold fish also generally have a tapered back body. Therefore, you can easily identify the gender from the side.
- During the breeding season, the female fish begin to produce eggs. This will cause a bulge on one side of the fish's body so that the body looks asymmetrical or one-sided.
Step 2. Notice the protruding anal opening of the fish
The anal opening of the female ornamental goldfish is rounder than the anal opening of the male. During the breeding season, this hole is generally more protruding.
- When viewed from the side, this hole will look like a protruding surface on the female fish's belly.
- In addition to the protruding anal opening, the anal fin of the female fish looks thicker than the anal fin of the male.
Part 2 of 3: Identifying the Males
Step 1. Note the presence of tubercles on the fish
One of the characteristics of male goldfish is the presence of tubercles (protruding white spots) near the front fin of the fish.
- Generally, tubercles only appear during the breeding season for fish. However, some adult males that have gone through the breeding season often have tubercles that are visible all year round.
- Tubercles may also be seen on the pectoral fins, face, and scales of fish.
- While a tubercle can indicate that a fish is male, a fish that does not have a tubercle is not necessarily a female. This is because not all male fish have tubercle.
Step 2. Watch for fish with smaller, leaner bodies
Male goldfish generally have a longer, smaller, and slender body than females of the same age and species.
Step 3. Pay attention to the sunken anal canal
Male ornamental gold fish have a small and elongated anal opening so that it looks like an egg. The anal opening of the male fish is also concave and does not protrude.
Step 4. Note the presence of a midline ridge (midline ridge)
If possible, look under the fish's underbelly for any jagged midlines. This is a prominent line that extends from behind the pelvic fins to the area near the gills. In females, this line is not very visible, or even non-existent.
Step 5. Watch for fish chasing other fish
One way to identify male goldfish is to observe their behavior during the breeding season.
- The male fish will chase the female in the aquarium. The male fish will continue to follow the female fish from below and sometimes he will head his butt.
- To force the female fish to mate with him, the male will also try to push the female fish to the side of the aquarium or plants.
- However, if there is no female, the male ornamental gold fish will still chase each other. Therefore, observe the body and behavior of the fish to find out the gender.
Part 3 of 3: Understanding the Difficulties Encountered
Step 1. Understand that sex differences will only be visible when the goldfish are fully grown
The sex differences between male and female ornamental goldfish will be clearly visible after the fish grow up. Male ornamental gold fish takes 1 year to grow up.
- However, the growth rate of ornamental goldfish depends on the sex and species. Some species of male goldfish take only 9 months to grow up. Some female goldfish may take up to 3 years to mature.
- Due to the lack of DNA analysis, identifying the sex of juvenile goldfish is very difficult. If you want to keep both male and female goldfish, it is best to buy at least 6 fish of the same species. Statistically, there is a 98% chance that at least 1 fish purchased is of a different gender than the others.
Step 2. Understand that there is no easy method for determining the sex of an ornamental goldfish, except by looking at the fish spawning process
Identifying the sex of goldfish accurately is very difficult, even some experts are still having trouble. This is because there are many exceptions to the rules made.
- Some male goldfish do not have a tubercle, but some female goldfish may do. Some female goldfish do not have a prominent anal opening, but some males may have one.
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In addition, some species of ornamental goldfish do not follow the general rules. For example, some breeds (such as ranchu or ryukin) have naturally round and large bodies. Therefore, it is almost impossible for you to identify the sex of a fish based on its body shape.
Tell if Your Goldfish Is a Male or Female Step 9Bullet2 - Therefore, it is better to know the sex of the ornamental gold fish by observing more than one feature.
Step 3. Understand that this method only applies to healthy goldfish
An unhealthy goldfish may not behave like a healthy fish during breeding season. In addition, fish may also not have body shape characteristics that can indicate a particular gender. It is important to ensure that the fish are in good health (by providing them with healthy food and a clean environment) before identifying their sex.
- For example, an unhealthy male goldfish may not have a tubercle during breeding season. Female goldfish may not have a convex anal opening.
- Body shape can also be misunderstood. A lanky goldfish might be considered a male (since males are generally smaller than females), but the fish may be an underfed female. On the other hand, you might think a fish's distended belly is a sign that it's a female, but the swelling could be a symptom of pineapple scale disease (an internal bacterial infection).
Tips
- Some goldfish enthusiasts believe that the males are more active and have a brighter coloration than the females.
- Visit the pet shop and watch for the large ornamental goldfish. This can help you learn how to sex fish more easily.
