Male and Female Sharks

Although males tend to be smaller than females, the easiest way to tell them apart externally is that males have a pair of claspers which are used for mating. There are a number of internal differences, most notably that males have two muscular sacs (siphon sacs) in their abdominal wall, they have testes to produce sperm and they secrete hormones that control the development of male characteristics. Females have a pair of ovaries where eggs are produced along with hormones that control the development of female characteristics.

Starry Smoothhound (Male):

Male Shark Morphology © Marc Dando.

Spiny Dogfish (Female):

 Female Shark Morphology © Marc Dando


Some types of shark (such as Blue Sharks and Spiny Dogfish) spend most of their lives in single sex groups. When they’ve reached maturity and are able to reproduce they’ll meet just once a year with the opposite sex in order to mate.

Courtship behaviour has not been observed in many species of shark, but the males of some species (such as catsharks) have been observed twisting their body around females before mating. The males of larger species, (such as Lemon Sharks and Nurse Sharks) have been observed swimming parallel to the female while biting their pectoral fin to hold her alongside him during mating. Basking Sharks have been seen following each other nose-to-tail and it has been suggested that breaching may form part of a courtship display.

Chemicals released into the water by females stimulate the male sharks. A shark’s courtship can be quite aggressive and female sharks often end up with teeth marks (or ‘love bites’) on their fins or back as a consequence of mating. However this aggressive display does not hurt female sharks as their skin can be up to three times thicker than a male’s.


Shark Reproduction