Hey ! They are pregnant seahorses ! Do you know that they are not female seahorses but..
they are actually the male seahorses that carry the eggs for about 9 to 45 days before the tiny seahorses emerge fully developed ! The male seahorse is actually equipped with a brood pouch on the ventral, or front-facing, side of the tail. When mating, the female seahorse deposits up to 1 500 eggs in the male's pouch.
( http://en.wikipedia.org/wiki/Seahorse )
Do you know that scorpion carries its young on its back ? The live female scorpions give birth to live young 2 to 18 months after mating, depending on the species. The newborns will immediately climb onto their mother's back, where they will remain for several days until their first molt (shedding of skin ). Some young will remain there much longer, depending on the species too. The mother will not feed them but she does carry them around and protect them until they are able to hunt and defend themselves.
However, suprisingly if the mother gets hungry, she will no longer recognize the young ones as her young but may eat them. That is why after the first molt, the young scorpions will leave to establish territories of their own and will be sexually mature after the sixth molt.
( http://www.sandiegozoo.org/animalbytes/t-scorpion.html )