Something in the water in Newport Bay

Last night in Newport Bay we saw 1 sunfish (my first this year!), 2 grey seals, 3 bottlenose dolphins including 1 juv. and also something large and unidentified breaching clean of the water! Whatever it was breached clean of the water 3 times, definitely not a dolphin and much too big to be a sewin - size closer to a dolphin. We never saw it surface again after those 3 breaches, so I'd lean towards a shark of some kind? Unfortunately it was just a bit too far away, the other side of the bay from us. If anyone else saw it just off Cat Rock at around 7pm last night please let us know!