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Aseela said...
Looking at the footage posted on 'the west' yesterday of the fishermen who spotted the GWS, I notice the shark circles around but it does not have it's dorsal fin right out of the water(Jaws style). It's more like a mullet swimming or the surface or bait fish impersonation. No real indication of what lies beneath! This is worrying.
It's in the sharks favour to not be noticeable, especially given one of their primary food sources are seals. Sharks like to cruise near seal rookeries and pick off the slow/weak ones that head out for fish. The sharks wouldn't do to well if they swam around with their fins sticking out of the surface, advertising their presence to the seals sitting on the rocks

Having said that, they still stick their fins out often enough that it's a habit that is exploited with satellite tags (attached to the fin) that only transmit data when they are exposed to the air.