Saturday, January 5, 2013

More juvenile seahorses (H. erectus)!

 Two day old sea horses feeding on Artemia (brine shrimp) nauplii picture below

The hatched nauplii (orange) settle toward a light source below, while the unhatched eggs (brown) rise to the top to be separated and then fed out as a regular part of the moon jelly diets, corals and juvenile seahorses

Juveniles hunt nauplii

Since the holidays, we have been exceptionally busy at the VLM, but were rewarded with a nice Christmas/New Years present, albeit a few days late. On January 3, the seahorses in one of our holding systems (the rest are on exhibit), became the parents of several dozen babies. Seahorse broods can vary widely in number, and this one is on the small side, but they are excellent eaters. So far, all are in good health and by the looks of a VERY gravid male, another batch is coming soon!



This handsome devil is the proud papa.

The babies are put into a special tank that is designed to eliminate any risk of them being sucked into a filter, or buffeted too roughly by current. Also, the flow in the tank must be gentle enough for the juveniles to capture food and gain strength as they grow. Because they are small and have some difficulty maintaining their positioning in the water column,  it can be awkward to feed efficiently so we provide them fishing line "hitching posts" they can wrap their tails around and hang onto as they feed. Sometimes they "perch" upright  from it, sometimes they lay on it and sometimes they hang from it sucking up food (below).

 Juvenile seahorse hanging on fishing line 

All of our seahorses are native lined seahorses Hippocampus erectus, a few of which have been bred here, most of which come from Mote Marine Laboratory - who have a widely recognized captive breeding and conservation program - but NONE of which are from the wild. Seahorse populations in this area and in many parts of the world are in decline, and some of the blame must go to the aquarium trade, public and private. Please do not buy seahorses from pet stores, or take them from the wild. The average person simply does not have the adequate resources to house and feed these animals properly and they are very susceptible to stress and disease. These beautiful little creatures have it tough enough without us loving them to death.

The male pictured above will soon produce offspring. Eggs incubate in his pouch (the dark leathery sac on his belly) for a few weeks and he may release hundreds of tiny seahorses. Survival rates in the wild are extremely low; even in captivity with constant attention and no predation a survival rate of 50 % is considered exceptional.

Pictured above is one of the seahorses that did not survive, as viewed through a microscope at 10x magnification



1 comment: