Nothing to see here.

Oh my god it’s Kelp!

Giant manta ray.

Pelican on the water and it casting a shadow on the wave? Or a pterodactyl

Kelp

Not to be devil's advocate here, but that could have been seaweed. It doesn't crest with the wave and disappears so fast. Strange for sure, though.

It's a sort of conglomerate of algae, or simply algae, which is not an uncommon phenomenon.

bizarre !

This makes me never try surfing again 🤣