Ankyra Sound one if by land, two if by sea

He had been basking in the warmth of the summer-warm sand when it began to move around him. The sensation was strange, but not entirely unpleasant. At least not until something jabbed at his belly and then his groin, each feeling more insistent than the last. As the boy shot to his paws he looked down at himself, thinking it was something wrong with him, and after a few seconds a soft looking rock popped out of the sand where he'd been settled.

Reyes was so focused on the shifting objects immediately beneath him that he failed to notice the plethora of others erupting from the earth, flapping their little fins in an attempt to creep closer to the water. He was perplexed by the presence of this weird rock and began to circle it, his eyes and ears trained down to where it sat while he moved around, around, around, sniffing and poking and then barking sharply, because what the hell???

He flipped the rock over, and it swatted at him, which was weird. He chuffed over it, licked it, nudged it with his nose again, and as soon as it was right-side-up the creature attempted to escape by veering towards the water too. It was during Reyes' attempted corralling of the weird rock that he nearly crushed another one shooting through the sand. The motion caught in his eyes and his attention diverted, only to shift again and again as more of the rocks became apparent. They were moving in droves across the dry sand towards the lower sections of the beach, where their fins scalloped at the wet surface. 

Reyes snorted and frowned, then charged after the horde of newborns — pointedly slamming his paws against them if they aligned beneath, or changing his trajectory to try and scoop them up and toss them this way, or that way, not understanding that it was nearly impossible for him to catch them all. What the heck was going on???