Shark Reproduction
Shark
Reproduction
There hasn’t been much research conducted in regards to shark
reproduction but a great deal is know about the process. The
conception generally takes place privately in the waters of the
ocean. In captivity very few sharks actually will mate so it
can’t be observed that way. Another reason that there isn’t
much research on the subject has to do with the fact that there
is no shortage of sharks out there.
Conception
One of the main differences between sharks and other animals
is that the males has claspers that they use to get the sperm
into the females. There is one on each side of the body and
they alternate which side to use. Some people have mistaken
these claspers for penises which is where they theory that male
sharks have two penises comes from.
The females emit various types of chemicals into the water
during mating season. Since they are normally living apart from
males, these chemicals attract them together. A sign that
sharks are going to mate soon is when the male is seen spinning
circles around the female over and over.
The males often let the females know they are interested in
mating by biting them in various places. Some researchers
believe these bite marks take place during conception too in
order to help keep the two sharks entwined for the process to
be completed. The females aren’t harmed by this biting though.
In fact, they have thicker skins and it is believed this is one
of the reasons for it.
Asexual Reproduction
There have been cases where female sharks in captivity have
had no contact with a male but become pregnant. This means that
asexual reproduction is a possibility with some type of sharks.
This could be a significant reason why they have been able to
evolve so easily and to continue with high population
numbers.
However, it is believed that asexual reproduction doesn’t
take place too often in the natural environment. This is due to
an abundance of both males and females out there to
successfully mate with. Some of the sharks in captivity who
have been part of asexual reproduction only have the DNA of the
female so this finding definitely lends credibility to the
concept.
Giving Birth to Live Sharks
There are species of sharks that give birth to live sharks
called pups. They only have a few at a time and they abandon
them after delivery. Baby sharks instinctively know how to
survive immediately. The mother shark goes on about her
business without giving them a second thought.
Laying Eggs
Other species of sharks will lay eggs in a well hidden area.
The eggs are in a protective case that makes it difficult for
predators to get to them even if they do find them. There can
be only a few or more than 100 eggs laid at a time by a female
shark. Since sharks don’t have very many enemies even the
little ones are often able to survive at a very high rate.
Sharks have always seemed to be able to reproduce at high
enough numbers that no intervention is needed. Yet there is
concern about the number of them dropping in their natural
environment. Sharks have become quite a commodity and that has
many animal activists concerned.
Some species of sharks have been placed in captivity to try
to help their numbers increase again. Yet they seem to have a
difficult time for the most part adapting to being in
captivity. Even when the environment is designed to
significantly resemble their natural locations they can tell
the difference. As a result it can hamper their reproductive
drives.
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