[harbour seal]

exoskeleton certainly narrows down the options:

- given the mobility likely not any mollusca (e.g., not some type of chiton), or at least any that i am aware

- arguably leaving arthropods --- specifically, isopods or shrimp seem likely candidates; however, most local species are both too small and don't tend to move in the fashion witnessed in the whytecliff creature.

Crangon communis - common two-spined crangon

i found a photo of this shrimp in one of my texts, in which it vaguely resembles the shape/colour/eyes you described; however, 8cm is the top of it's size range and (in my limited experience) shrimp tend to display characteristic and recognizable motility. i don't think this is what you saw but it is the best candidate i found thus far.

possibly the creature has extended it's range farther north and thus not previously described in this area. for example, in 2004 the infamous humbolt squid literally invaded our waters (off northern washington and southern vancouver island) in substantial numbers. prior to that time it had not been recorded this far north (outside of the odd single and infrequent occurance usually washed ashore). perhaps these occurances may be "adjustments" to the effects of climatic shift?

if you figure it out be sure to let us know.

cheers,
sean