Safety in numbers they say. Look at these babies, clinging together like a miniature wheel.
Newborn seahorses tend to move in a group like this. This is because in their earlier phase they live in the upper water column, floating along with the planktons which are their main source of food, compared to the adult seahorses which mostly live in the benthic area (the seabed) where dense underwater plants grow. Because of this, baby seahorses will use anything - debris, floating weeds, and even their siblings' tails - as holdfasts. As a result, cute tiny wheels of baby seahorses.