do catfish have periods

Do Catfish Have Periods? (catfish menstrual cycles)

As a human, it would be typical to think that most other living creatures would have similar anatomy to you. It would be easy to assume that female animals such as fish or more specifically, female Catfish would experience menstrual cycles just as female humans do. You will be surprised to find out though, that fish are oviparous animals. Meaning, they are an animal that lays eggs instead of mammal-like child labor.

Do catfish have periods? No, catfish do not have menstrual cycles.  No oviparous or egg-laying animals will ever experience periods. Their anatomy is simply different than mammals, and they don’t have uteruses for lining to shed.

Read on to learn about the different stages and life cycles of catfish and overall general fish reproduction. Discover interesting facts about how most fish parent (or don’t parent) their young. Learn about the ongoing issue of rising catfish populations (hint: catch more catfish!), and other types of animals that don’t have periods!

Egg Stage

Before we can have fish, we must have a fertilized egg. Most female catfish will build a nest to house their eggs, and the male will come to the nest to fertilize. This depends on the breed though, because some breeds of catfish do things differently.

catfish spawning den
The spawn of a catfish in a spawning den

Most eggs will not make it to complete maturity, even with superb conditions. Eggs face many threats at such a young age, such as; predators, temperature and oxygen changes,  natural disasters, or disease.

Larval Stage

The larval stage is the next part of the growth process for baby catfish.

Unfertilized or failed eggs will attach to viable eggs, and the viable baby larval will feed off of these abandoned yolk sacks until they can reach independence.

The yolk sacs are attached to the larval’s bodies, and once absorbed the fish are independent and called fry.

Fry Stage

The fry stage is one where the baby fry can begin eating on its own.  Most species of fish consider their young fry from about two months until they reach adulthood or sexual maturity. Some species have a juvenile period, but most catfish do not.

Typically, catfish are considered fry until they are nine to twelve months old when they reach sexual maturity.


The juvenile period is a period only some species of fish have. Species that have this period typically have longer lifespans and reach sexual maturity later in life.

For example, two breeds of catfish that have a juvenile period are hardhead and gafftopsail catfish. They both do not reach sexual maturity until about two years old. So, from around twelve months until around two years old, these catfish are called juvenile.

Adult Stage

Once a fish has reached sexual maturity, it is considered an adult or fully grown fish. While most fish do grow to an average size at this age, it doesn’t mean they are fully done growing in size.

Fish can grow larger over time just as humans can. All species of fish reach maturity at different times in their life.

For most fish, it is usually between one to three years. A longer example would be sturgeon, which lives for 80-150 years. They reach sexual maturity at twenty-five.


Spawning is the process of laying and fertilizing eggs for reproduction. Typically, female fish will lay eggs in a nest or hidden area. Male fish will come and fertilize those eggs.

Then, the process repeats itself over and over again.

Female catfish will typically spawn once a year, sometimes more if none of her eggs are fertilized. Female catfish can spawn up to once a week until fertilized if conditions stay correct.

Males will fertilize from September to May of every year.

Interesting Parenting

Some species of catfish have some interesting twists on spawning!

Saltwater catfish are often mouthbrooders, meaning after the eggs are fertilized, the paternal fish carries the eggs around with him in his mouth, until they hatch.

This is super beneficial for these fish because their females don’t spawn as many eggs as typical fish do. So by the male protecting the eggs, they aren’t as likely to lose eggs for natural reasons.

Where Catfish End Up

Although being born to the areas their parents are local to, can catfish travel or migrate? Most of the time, catfish have seasonal migration patterns that decide where they will be in certain months. Daily, catfish can travel anywhere from ten to twenty miles a day. Catfish are one of few fish that have a special organ that allows them to communicate with one another underwater, so they tend to stay in groups.

Adulthood Past Breeding

Catfish aside from breeding will feed all day and night long. They spend their time prowling the bottoms of oceans, rivers, lakes, and ponds looking for food.

Types of things catfish enjoy eating are shrimp, insects, algae, larvae, smaller fish, crustaceans, anything dead. Catfish are essentially the vulture of the sea!

Catfish even in old age tend to stick with their crowd, meaning hang out with a pack of usually 4-10 other catfish.

Catfish Populations

Catfish are all over the world. Some of the most common types of catfish are channel catfish, blue catfish, flathead catfish and hardhead catfish and gafftopsail catfish.

Channel catfish are located all over the United States, being the official fish of Kansas, Missouri, Iowa, Nebraska, and Tennesee.

There is an abundance of blue catfish in the Chesapeake Bay, in Virginia, and in Wisconsin.   Flatheads are local to the great lakes of Michigan to the  Mississippi, Missouri, Ohio, and Rio Grande river basins.

Both hardhead and gafftopsail catfish are local to Florida and the Gulf of Mexico.

Other Animals Without Periods

Any animal that is not a mammal will not have a menstrual cycle or period. Although not all mammals have what we call periods exactly, that’s for another topic. For example, reptiles do not have periods.

Birds, also do not have menstrual cycles. Another mammal that does not menstruate, whales.

Most animals, in fact, do not have periods, it’s an unknown rarity to a couple of species including humans.

Conclusion – Do Catfish Have Periods or Menstrual Cycles?

So luckily for catfish, they don’t have to experience periods. Although we don’t know what it’s like to be oviparous and lay eggs, it might even feel worse than childbirth.

The reproduction cycle of a catfish starts at the egg stage, where eggs are laid and fertilized. The next step is the larval process, where the unfertilized eggs attach to the viable eggs, feeding them throughout the rest of this stage. Once those yolk sacs absorb into the baby fish, it is now called a fry. A baby is considered a fry until sexual maturity.

A fish may be considered a juvenile in-between the fry and adult stage if it has a particularly long lifespan. Once the catfish reaches the adult stage, it is sexually mature and ready to reproduce. Catfish reproduce through spawning which is just the process of laying eggs.

Some catfish interestingly carry their eggs in their mouths while incubating. Catfish like to travel in groups of around four to ten fish of their kind. Surprisingly, periods are not as common as you would think. Most animals do not experience periods, and definitely not oviparous or egg-laying animals.