Dolphin or porpoise?

[jmack]

I'm sure someone can help explain the difference between a dolphin and a porpoise fin. This was taken a few days ago from the Arran ferry.

[ChrisJB]

Harbour porpoises. They have a small triangular dorsal fin and their backs come out of the water in a rotating manner.

Chris

[tom00_uk]

there are a few different species of dolphins found in Uk waters, each one is different

the whale and dolphin conservation society have a good site showing you the species around the world.
Welcome to the WDCS Species Guide

in general porpoises are not acrobatic, they roll through the water and have the dorsal fin far along the back. they also have a vocal range that does not travel far through the water, though you will need a hydrophone

dolphin's tend to be much more acrobatic and will bow ride they also porpoise (swimming fast with a clear jump from the water whilst cruising along, also done by sea lions, penguins but very rarely porpoises)

[STYRBJORN]

Plesiosaur.

[Adam Cheeseman]

Originally Posted by ChrisJB

Harbour porpoises. They have a small triangular dorsal fin and their backs come out of the water in a rotating manner.

Chris

Watched many porpoises doing their slow, rolling motion as they swim along. Seems that they hardly move along before surfacing again, unlike dolphins.

Cheers,

Adam

[jmack]

Thanks for the replies, I noticed the rolling movement you mentioned that porpoises do. A great treat to see them even for a fleeting glimpse.

[~T~]

Originally Posted by STYRBJORN

Plesiosaur.

I was gonna say kestrel but now you mention it..