Dear Kelly:
Welcome to the Club and congratulation on your new brood of Hippocampus reidi babies!
It is not unusual for a pregnant male to give birth to a few babies a bit prematurely, and then temporarily suspend operations, only to deliver the rest of his brood as usual a day or two later. That seems to be what has happened in your case, but a brood of 50 would be abnormally small for a mature reidi stallion, so I suspect you are correct — it seems likely that more newborns (perhaps several hundred more) will be forthcoming shortly.
As I was discussing with Amber recently, Hippocampus reidi, the Brazilian breeding machine is the most prolific of all the seahorses (Abbott 2003). They have a well-deserved reputation for churning out brood after brood every two weeks with relentless regularity, and hold the world record for delivering ~1600 young in a single brood (anecdotal reports of broods up to 2000 fry are not uncommon)! So the festivities may just be beginning and there could be a lot more babies on the way.
In seahorses, a hormone known as fish isotocin, which is the equivalent of oxytocin in mammals, triggers parturition or giving birth (Vincent, 1990). Thus anything that stimulates excess secretion of isotocin can result in premature births, whereas anything which decreases or delays the secretion of isotocin can postpone delivery and prolong a pregnancy abnormally.
So there’s not really much a hobbyist can do to hurry things along when a stallion appears to be experiencing an extended pregnancy. Make sure his mate is present (i.e., don’t isolate the male in a paternity tank), maintain optimum water quality, keep the water temperature in the comfort zone, keep your dissolved oxygen levels high, and keep the aquarium as stress-free as possible. Other than that, Kelly, all you can do is relax, give your pregnant male plenty of peace and quiet, and let nature take its course.
If you do a search on this forum for the words "reidi rearing tips," you should find some useful suggestions for raising this challenging species.
Best of luck with your prolific ponies and all their progeny, Kelly!
Happy Trails!
Pete Giwojna, Ocean Rider Tech Support
Ocean Rider, Inc. is an Organic Hawaiian-Based Seahorse Aqua-Farm & Aquarium that Follows Strict Good Farming Practices in Raising Seahorses and Other Aquatic Life.
