字幕表 動画を再生する
Dolphins are extremely intelligent mammals which are part of the family that include
pilot whales and Orcas.
The are found around the world and in shallow waters around the continental shelves.
Dolphins are carnivores that mainly eat squid and crustaceans.
They are generally grey in colour with darker backs and lighter undersides.
They use echolocation to help them hunt and navigate the oceans. They listen for echoes
and their senses help to guide them around.
They are very agile creatures and are known for their playful behaviour.
In order to view their surroundings, they will spy-hop which is where they will rise
up vertically out of the water.
It is thought that dolphins look to conserve their energy by swimming alongside ships,
a practice known as bow riding.
They are social animals and will live in groups together often synchronising their movements
with one another. By being in groups, they can hunt more effectively and protect one
another.
In order that they can sleep half of a dolphins brain is asleep whilst the other half stays
awake so they can continue to breathe and stop from drowning.
Dolphins tend to mate throughout the year but there are seasonal peaks in spring and
fall.
Depending on the species, they will have a gestation period of between 9 and 17 months
and by the time they are ready to give birth, they will distance themselves from the rest
of the pod and travel towards the surface and give birth.
Dolphins will usually give birth to one calf a year. Twins have been evidenced but are
rare in the Dolphin world as soon as a calf is born it will be taken to the surface so
it can breathe.
The Dolphin will nurse the calf for between 11 months to 2 years. Once it has been nursed
it will stay with its mother for anything between 3 and 8 years old.