The colour and eye-stalks threw me, so I had to have the two side by side and go over each part and limb just to make sure they were different characters... and they aren't even redecos of each other.
I guess they are both red because that's the colour of crustaceans when they are cooked... which is what westerners are more familiar with.
Bisk is obviously lobster themed (base on the name), so I think Clampdown is crab themed.