Cool....must have been a good experience! They are amazing mellow creatures.

Not sure what I saw today but I saw a fin between me (and about 8 surfers) and the beach down at Woolamai.
If it was a shark I'd guess it would have been around 5ft long (going off the size of the fin). It didn't make a second
appearance which makes me think it wasn't a dolphin or seal as they tend to pop their heads up and hang around for
a while.

Anyway...I kept it to myself and everyone had a good surf. Should I have told people in the water?

The dorsal fin on those mantas is a pretty good match for a white pointer fin - under the right conditions with a big one slicing through the dusk lineup I reckon there'd be some deckpads that would need cleaning.

On the topic of sharks - I was out in the boat a few kms offshore and the place was lousy with small hyperactive hammerheads - all about 3' long. Real nervous things darting in and out, this way and that. I was chucking a hookless popper out there to see what would happen, lots of follows, but no big hits. Would've made a heaps better video than the mantas.