dw5448's picture

Harbour porpoise at Newcastle

Observed: 2nd May 2010 By: dw5448
S159 Neighbourhood Nature - course complete
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2 or 3 of 6-8 porpoises feeding for about 30 minutes then moving south along the coast. First image just shows countershading. Last image shows tailstock during dive

Species interactions

No interactions present.


the naturalist man's picture


The relatively triangular dorsal fin indicates porpoise. In dolphins the dorsal fin is far more swept back with a very curved leading edge. Though your first photo looks to be of an animal with a curving leading edge to its dorsal fin it is not curved enough to be a dolphin.

Graham Banwell

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dw5448's picture

Definitely HP

There is some variation in dorsals - I think the triangular idea is to contrast with the big dolphin "sickles", as you say. Because dorsals are not being used for individual ID in this species (unlike bottlenose), I think we don't look at them often enough.

I have seen this little group before I think - the one that rolls high and shows the lighter underside has been around for a few months I think, though I can't prove it really is the same individual.