Sharks come in over 400 different varieties. That explains why the sharks look, hunt, and live in such a variety of ways, given their differences in appearance. Reproduction is affected as well by these distinctions. The way that sharks reproduce varies.
Do sharks produce eggs? Are they able to reproduce live young? Let’s begin by addressing the following queries.
Sharks may reproduce in three ways: viviparity, oviparity, and ovoviviparity. Sharks may reproduce via asexual reproduction in certain unusual circumstances.
The biology and habitat of a shark determine how they reproduce. The likelihood of a shark producing live young increases when the species is used to living in the open ocean. Eggs are more likely to be produced by a shark that lives closer to shore.
How Do Sharks Reproduce?
The reproductive organs of a shark are startlingly similar to those of many other animals.
Claspers are the male shark’s reproductive organs. For the majority of shark species, it is long and can be found on the pelvic fin. The clasper is actually located on the head of chimeras.
Females, on the other hand, have oviducts. The oviduct is a lengthy tube that connects the female’s womb to her exterior half of her body.
The male will inject his clasper into the female’s oviduct, where he will create sperm to fertilize the eggs during mating. In comparison to other animal species, sharks don’t mount one another. During mating, the two sharks will swim side by side instead.
How do Sharks Mate: Sharks Mating Habits
Unfortunately, when sharks mate, we don’t know much about their habits. In the wild, it’s tough to locate and watch mating sharks, and even those that do reproduce in captivity will not breed.
Depending on the species, it can take years, even decades, for a shark to reach sexual maturity.
Most sharks, according to researchers, will travel to open seas during mating season. Nevertheless, most sharks prefer to deposit their eggs in protected coast nurseries: shallow areas.
Bite marks on female bodies from male counterparts have also been observed by researchers. It’s also unclear if these assaults are caused by the male attempting to mount them or by a result of the mating ritual.
It’s also known that sharks do not produce many young at one time. Many species of animals will produce a large number of young at once in the hopes that some of them will survive. Usually, because there are so many babies produced, they aren’t of the greatest quality.
Sharks are also said to have a limited ability to reproduce many offspring at once. In the hopes that some of the young will survive, many species of animals will give birth to a large number at once. They aren’t usually of the highest quality since they’re produced in such high numbers.
Sharks appear to favor quality over quantity. Different species will have between 2 and 100 juvenile at a time, rather than numerous young.
Sharks appear to favor quality over quantity. They might have around 2-100 young, depending on the species, rather than having a lot of them all at once.
Ways of Shark Reproduction
Live birth is referred to as viviparity. The most advanced kind of reproduction is thought to be the production of live young by over half of all cartilaginous fishes. Sharks spend the majority of their time in the open ocean, which is why they have such a high rate of birth this way.
Shark bodies must be able to sustain live young in order for them to be able to produce offspring. The fetuses may absorb nutrients and breathe while inside the reproductive tract thanks to evolutionary developments that occurred throughout their development.
In the same way that mammals do, they receive nutrients and oxygen from their mother’s umbilical cord. After that, the babies will subsist on the placenta.
However, unlike mammal viviparity, juvenile sharks are self-sufficient almost immediately after hatching. The eggs of most mother sharks do not hatch before the shark is gone. They simply lay their eggs and go on their way after finding an ideal location for them.
Pup counts in viviparous sharks are usually between 2 and 20, with a few exceptions.
These sharks’ eggs aren’t buoyant, so they wouldn’t be useful in the open ocean where they spend most of their time. Adults may also dominate pelagic (open ocean) zones because they do not lay eggs, as opposed to when they do.
Some of these shark species, meanwhile, are unable to create a lot of eggs. They do, however, create live young instead. Live young produced by sharks have been shown to have a greater survival rate than those produced in eggs, according to researchers.
Below are examples of common viviparous sharks:
- Blue Sharks
- Silvertip Sharks
At around the age of 4-6, both male and female Blue Sharks reach sexual maturity. The male will bite the female to connect with her when they are ready to mate. Researchers believe that due to this biting ritual, females have developed skin three times as thick as males. After that, the male will place his clasper into her to fertilize her.
Blue Shark pups develop inside their mother, as I previously said. A yolk sack provides them with nutrition. The yolk sack is turned into a placenta, from which the mother will provide nutrients after all of the nutrients have been removed.
The mother will produce a litter of 5-135 pups after a 9-12 month gestation period.
The female will give birth to a litter of 5-135 pups after a nine-to-twelve-month pregnancy.
When a female silvertip shark grows to be 6.5 feet (2 meters) long, she becomes sexually mature. At 5.9 feet/1.8 meters, the males reach sexual maturity.
The male will keep the female when they’re ready to breed. Bite marks have been seen on the bodies of many female sharks as a result of this. Several of them have been observed with a section of their dorsal fin missing.
During the summer months, mating season and birth take place. The pups are born in the summer a year after they are conceived, since the gestation period is typically around one year.
The pups will consume a yolk sack throughout pregnancy. The yolk sack transforms into a placenta from which the pups will nourish once the nutrients in it are depleted.
The mother will deliver her baby in shallower waters when she is ready. She will have litters of one to eleven pups. A litter of 5-6 pups is the most prevalent. The pups are around 25 to 32 inches long when they are born, ranging from 63 to 81 centimeters. Before they go their separate ways, the pups have been observed swimming with the mother for a brief period.
Other viviparous sharks include:
- Blue Bull Sharks
- Hammerhead Sharks
- Lemon Sharks
- Mako Sharks
- Porbeagle Sharks
- Requiem Sharks
- Salmon Sharks
- Sandbar Sharks
- Sharpnose Sharks
- Sliteye Sharks
- Whale Sharks
- White Tip Reef Sharks
- Whitecheek Sharks
- Whitenose Sharks
The most frequent manner of fish reproduction is oviparity, which refers to the production of eggs. Skates and chimera, as well as sharks, are the most common species that exhibit this type of reproduction. Oviparity is used by around 40% of all shark species to reproduce.
Hormones such as progesterone and estrogen help to develop the eggs, or ova, in the female’s ovaries. The eggs develop a leathery, tough texture.
The eggs are fertilized in the womb before being laid, which makes sharks “real” oviparous. The eggs may take anywhere from 6 to 9 months to hatch. The length of time a shark takes to gestate is influenced by such variables as water temperature and species.
The mother shark does not spend the entire gestating period inside her. Before she lays the eggs, the mother will typically keep them inside her for many weeks. The eggs are not completely formed when she deposits them. Before they hatch, they will spend the remainder of their pregnancy in the water.
The eggs are not merely spread throughout the water column. Instead, the mother will spend a long time looking for an appropriate nesting site. They’ll often place their eggs in nurseries alongside other sharks, rather than releasing them.
The eggs will frequently have appendage-like attachments that stick them to a surface. The eggs might include horns, sticky mucus, or tendrils that aid the egg stay put. Eggs are frequently eaten by predators, even with this extra protection.
On beaches, for example, a mermaid’s purse is frequently discovered. The tendrils on this egg sack aid it to stay put, and it comes from a skate or shark’s abdomen. You can identify which egg sacs belong to which shark species based on its features if you examine photographs.
On rocky bottoms, coral reefs, seaweed, and even the seabed, eggs may frequently be found adhering to them. Until the embryo develops sufficiently to hatch, the egg will stay there.
The fact that each egg contains a yolk is a prominent characteristic of oviparity. Until the embryo hatches, the yolk is absorbed, allowing it to obtain the nutrients it requires. The embryo will have grown into a tiny replica of the adult shark when it is ready to hatch.
Depending on the species of shark, the size of the eggs and quantity of eggs produced changes. Some species lay more eggs than others, and some are significantly bigger than others. Oviparity-reproducing sharks produce between 10 and 200 eggs on average.
Depending on the shark species, the size of the eggs and number of eggs laid may change. Certain species lay more eggs than others, and some are considerably bigger than others. Sharks that reproduce via oviparity usually create 10 to 200 eggs.
Below are a couple of oviparous sharks:
- Bamboo Sharks
- Port Jackson Sharks
Port Jackson Sharks
Around 11-14 years of age, female Port Jackson Sharks reach sexual maturity. At the age of 8 to 10, the boys will reach sexual maturity. They will only breed once a year.
Males and females stay apart from each other for the most part of the year. They will only come together to breed after spending their lives in different habitats. Between the months of July and August, mating takes place.
Since it has never been observed, researchers are not entirely sure about the entire mating process. They have also found that during the shark breeding season, these sharks are more likely to spend time in caves and ledges. These sharks have also been observed to spend longer periods of time at the ocean’s bottom.
Between August and September, the female will produce egg cases after fertilization. The egg cases are dark brown in color and have a spiral structure. She’ll lay ten to sixteen eggs in shallow reefs and leave them there. Between 16 and 100 feet/5 and 30 meters deep, the eggs are most often found.
Every year, female Port Jackson Sharks deposit their eggs in the same spot. To safeguard the eggs from predators, they will place them inside the cracks of rocks when they create them.
Males will immediately return to greater water after mating. As soon as the eggs are deposited, the females will join them.
Before they hatch, the eggs will need around 10-12 months to develop. The pups are around 10 inches/25 millimeters long when they emerge from the shell. Juveniles will spend their lives in bays and estuaries, unlike adults.
The male Horn Shark will pursue the female when they are ready to reproduce. They will sink to the ocean floor, where the process will begin, when they are both ready to mate. The guy will bite the lady and clasp her in his arms. After that, the male will place his clasper inside the female, and the two will mate for roughly 30-40 minutes.
Between December and January, Horn Sharks begin to breed. She will deposit the eggs just a few weeks after because the females don’t hold onto the eggs throughout the pregnancy period.
Horn Sharks don’t deposit all of their eggs at the same time, which is surprising. Instead, they’ll lay two eggs at a time. They can deposit up to 24 eggs in total and lay two eggs every 11-14 days. Between February and April, the entire process may take place.
The female shark will deposit her eggs in shallow water after she lays them. To try to keep predators at bay, she’ll conceal the cone-shaped egg cases in the nooks and crannies of rocks.
The eggs will then take around 6-10 months to fully develop from there. The rate at which the eggs develop is determined by the water’s temperature.
The pups will be around 6 to 7 inches/15 to 17 centimeters long when they hatch. They take a long time to grow, and they won’t start eating until around a month after hatching.
Other oviparous sharks include:
- Epaulette Sharks
- Necklace Carpet Sharks
- Bamboo Sharks
- Swell Sharks
- Zebra Sharks
Ovoviviparity is the most complicated of the three reproductive modes. In reality, ovoviviparity is a mix of viviparity and oviparity. Sharks that develop eggs through ovoviviparity are called ovoviviparous sharks. The eggs, though, will hatch while still in the mother’s womb, allowing the juvenile sharks to emerge.
The mother does not create a placenta like she does in viparity birth, therefore this is similar to viparity. Instead, before they hatched, the embryos will feast on the egg’s yolk sack. Despite the fact that the mother does not have a placenta, she supplies oxygen to her kid.
The eggs will be laid and developed wherever the mother places them, whereas sharks that create eggs through oviparity will lay them. The eggs are carried inside the mother’s body in ovoviviparity, and they will develop there.
Because it provides protection to the eggs, this method of producing and developing eggs is preferred. The eggs are typically exposed to predators while they are oviparous. The eggs may develop completely inside the mother before hatching with ovoviviparity, which ensures their safety.
Ovoviviparity produced eggs have a fragile membrane that is simple to break out of, as opposed to oviparity, where the egg cases are tough. The mother will deliver the pups when the juvenile is fully developed. Ovoviviparous sharks typically bear 1 to 8 pups.
Pups may be born up to a week after they emerge from their eggs, in certain cases. The pups of some species may feed on the eggs that are not fertilized while residing inside the uterus. Oophagy is the term for eating unfertilized eggs.
Intrauterine cannibalism is practiced by pups in some species, such as the Sand Tiger Shark. The pups that have emerged from their eggs will prey on their undeveloped siblings at this point in time. To ensure that only the strongest puppy survives, the first puppy to emerge will do this.
Here are examples of ovoviviparous sharks:
- Nurse Sharks
- Tiger Sharks
Around the age of ten to fifteen, male Nurse Sharks reach sexual maturity. Around the age of 15-20, females reach sexual maturity. When the male inserts his clasper into the female, he will bite her to hold onto her.
She will give birth between June and July, and Nurse Sharks have a six-month gestation period. Young are produced once every two years by these sharks. She is physically unable to reproduce for another 18 months after she has given birth to one clutch of pups.
The female will typically have roughly 30 pups at a time when she gives birth. The pups, on the other hand, are cannibals. The smaller and weaker pups will be devoured by the bigger and stronger ones. There could be fewer than 30 pups left once everything is completed.
Pups are spotted at birth and are around 12 inches long/30 centimeters long. With time, the marks will fade.
Every year, tiger sharks may travel thousands of kilometers across the water. As a result, researchers have a difficult time studying them because so much of their reproductive practices remain unknown. Unfortunately, female sharks’ whereabouts during pregnancy are unknown to scientists.
At a height of 7.5 feet (2.3 meters), male Tiger Sharks reach sexual maturity. At 8 feet/2.5 meters, females will reach sexual maturity. Males will grip the female with his teeth while inserting their clasper inside her in order to mate.
Between March and May, the species reproduces, with babies being born between April and June of the following year.
A female Tiger Shark’s pregnancy lasts around 15 months. Ten to 80 pups, ranging in size from 75 to 29.5 inches, will be born.
Other ovoviviparous sharks include:
- Cookiecutter Sharks
- Crocodile Sharks
- Greenland Sharks
- Gummy Sharks
- Great White Sharks
- Pacific Angel Sharks
- Pelagic Thresher Sharks
- Pygmy Sharks
- Sand Tiger Sharks
- Soupfin Sharks.
Sharks may occasionally reproduce asexually, although this is unusual. The female shark can reproduce independently of a male by reproducing asexually. She accomplishes this by genetically reproducing herself, which results in a copy of herself that is similar or identical to her.
There have only been two documented cases of this phenomenon in sharks, and it is extremely uncommon. When there are no other sharks around them in the wild, female sharks are most likely to reproduce this way. When kept in captivity, they may also breed this way.
This is due to the fact that it is an unideal method for sharks to reproduce. The species will be more genetically restricted if the young’s genetics are limited solely to the mother. It may possibly cause illness and mutations if it happens over enough generations.
Interesting Shark Reproduction Facts
Sharks are extremely sophisticated animals. Their reproductive processes, on the other hand, make them more intriguing. Some interesting facts about shark reproduction that you may not have heard before:
- Some female sharks will mate with several males. The sperm from all the males may then be used to generate the young. As a result, even though they were born at the same time, the pups in her litter might have different dads.
- Sharks have lengthy gestational periods, as I’m sure you’ve already discovered. A Dogfish Shark’s pregnancy may last up to 24 months, in particular. Of any vertebrate, this is the longest gestational period.
Why Are Sharks Threatened?
Sharks are threatened by a variety of factors, including humans. Their meat, oil, and fins are all hunted. They’re trapped and murdered as a byproduct of fishing for another species. Pollution, littering, and environmental change are all having an effect on them.
Sharks, on the other hand, have a hard time recovering from these dangers. Their long reproductive cycle is the direct cause of this.
Some shark species do not reproduce every year. Every other year is the maximum reproductive period for some species.
The pregnancies are long-lasting, and only a few pups are born when they do reproduce. Gestation lasts between 9 and 12 months for most sharks, but up to 31 months for some species.
Each reproduction of a species of shark may result in as few as two pups. The Blue Shark, which may have up to 135 sharks, is responsible for the greatest number of pups produced. Even that isn’t enough, which may seem like a lot.
Millions of eggs may be laid at one time by several types of fish. Even so, the threat of overfishing continues to endanger many fish species. Imagine how the sharks are faring if fish can reproduce at much faster rates and remain in danger.
So, it’s a pretty remote possibility that the babies will survive to have their own offspring if the mother shark reproduces and gives birth. There is no difference between juvenile and adult sharks in most nations that hunt them. Unfortunately, since many shark species take years to reach sexual maturity, they die before they have a chance to reproduce.
How Do Sharks Mate FAQs
1. Are Male Or Female Sharks More Aggressive?
It appears that there isn’t a straight yes or no answer regarding whether male or female sharks are more aggressive. Because of their greater size, males are typically perceived to be more dominating than females. Although this might not always be the case, it does suggest that they are more aggressive towards other animals.
Males, on the other hand, may be quite aggressive during the mating process, causing bite marks on females’ bodies. Females have also been reported to avoid males for this reason, according to researchers.
2. Do Sharks Have Belly Buttons?
The short answer is yes, some sharks do have belly buttons. It may seem ridiculous, but it is true. While inside the mother’s womb, viviparous sharks, which give birth to live young, are linked to a placenta.
Once the mother and offspring are no longer connected, a placental link causes the creation of a belly button, as it does in mammals.
A shark’s belly button will fade in a few years, unlike humans, where it is plainly visible throughout their lifetime. It doesn’t appear to be a human belly button, either. Instead, between the pectoral fins, it appears as a scar.
3. How Many Babies Do Sharks Have At A Time?
The species of shark determines the best response. The litter size of viviparous sharks is likely to be lower than that of shark species that lay eggs. Even so, most sharks have a litter size of 1-100.
It doesn’t begin that way, however; some sharks only have one or two children. Inside their womb, they will have a large number of fetuses. When the bigger pups emerge from their eggs, they will devour the smaller ones until only one of the two is left.