Humans are fascinated by sharks. They're sleek, scary and amazing creatures of the ocean that both fascinate and terrify many. It's no wonder many people find themselves wondering how these huge toothy fish reproduce.
But with over 440 species of sharks existing around the world, asking about sharks mating rituals is a bit more complicated than it seems. Each species of shark approaches reproduction a bit differently. However, there are certain elements to shark sex and attracting mates that are similar in all species.
The Difficulty in Observation
The main problem with observing shark mating habits is the fact that these animals live deep underwater. While some sharks live and mate in the shallows, many sharks travel hundreds of miles in deep oceans where their mating habits haven't been observed.
Sexual and Asexual Shark Reproduction
Most sharks reproduce sexually via internal fertilization. However, there are certain shark species that can reproduce asexually.
For example, the female zebra shark can switch from sexual to asexual reproduction in the absence of male sharks. Female sawtooth sharks have also been observed to produce offspring without mating with a male. While asexual reproduction in sharks is extremely rare, it is possible for some species.
For sexual reproduction, the male uses reproductive organs called claspers that are at the back of the pelvic fins. These claspers transfer the shark's sperm to the female's oviduct, which is an opening that leads to the female shark's eggs.
General Shark Mating Habits
Each species of shark is going to have a slightly different mating ritual and different mating habits. However, scientists believe that a few commonalities exist between all shark species.
The first is the emission of chemicals by the female sharks. These chemicals signal to males in the surrounding area that the female is ready to mate. These chemicals are called pheromones and are common in other animals as well. As many sharks live alone and not close to other sharks in their species, this is essential for the sharks to find each other when they're ready to mate.
Biting to Stabilize
In terms of the actual act, you can imaging that it's a bit difficult to mate underwater with no hands or limbs to stabilize your movement. That's why many male sharks are observed biting the females during the mating process in order to stabilize them during reproduction.
This doesn't usually hurt the female as their skin is tough and thick (oftentimes twice as thick as male shark skin), although scientists do observe bite marks all over their body, which suggests multiple males will mate with the same female.
Some scientists suggest that the biting of the female is also to get the interest of the female. These bites are also considered a part of the courtship ritual as oftentimes the biting of the female doesn't occur during the physical mating but right beforehand. At the end of the biting phase, the male will bite the pectoral fin of the female and insert one of his claspers into the female.
Other observations include apparent dances or acts of strength to attract mates, although these observations are rare.
Great White Shark Reproduction
Great white sharks are perhaps the most popular and well-known shark species for their humongous size and use in pop culture like "Shark Week" and the movie Jaws.
However, great white sharks have never been observed mating or performing any type of mating ritual. Scientists believe that this is a combination of the long migratory habits of the white shark, long gestation/reproductive cycles and low overall numbers. In fact, most shark species have not been observed mating for these same reasons.
- World Atlas: How Many Species of Shark Are There?
- Science Alert: Zebra Shark Makes World-First Switch From Sexual to Asexual Reproduction
- LiveScience: Animal Sex: How Great White Sharks Do It
- Smithsonian Magazine: Meet Eight Species That Are Bending the Rules of Reproduction
- DNR Hawai'i: Hawai'i Sharks Mating and Reproduction