For the first time ever at the Monterey Bay Aquarium, one of our weedy sea dragons (Phyllopteryx taeniolatus) is carrying eggs. In late April, aquarists saw the animals performing a courtship dance. When they came in the morning of April 27, the male was carrying about 30 eggs. (Male seahorses and sea dragons carry the babies, not females.)
At first we didn’t think the eggs were viable. But a few weeks later teeny tiny eyes were peering at aquarists from some of the eggs. We’re not sure how many of the eggs are currently viable, but it’s still a positive sign, and we remain hopeful we'll have baby "weedies" someday soon! Regardless, it’s another success story for our Secret Lives of Seahorses special exhibition; all eight seahorse species on exhibit have now had babies at the Aquarium. Two pipefish species on exhibit have had babies, and one seahorse species not on exhibit has had babies. In the U.S., only three other institutions have had weedy sea dragons reproduce: Aquarium of the Pacific, Georgia Aquarium and Tennessee Aquarium.
Unlike seahorses, who carry eggs in a bulging brood pouch, sea dragons affix them to the undersides of their tails for the duration of the pregnancy. After courtship, the female pushes the eggs onto a soft patch of tissue on the male’s tail. This tissue then surrounds the fragile eggs and holds them in place.
Not all eggs make the transfer; aquarists found some on the bottom of the exhibit. But a large number did make it, and are now clearly visible on the tail of the new father.
In the viable eggs, tiny sea dragon embryos will develop for a period of about five to six weeks. Before then, aquarists will “isolate the male in a small floating cage within the exhibit,” says Jonelle Verdugo, associate curator of fish and invertebrates. “The male can still swim around, but we want to isolate and protect the babies as they hatch.” Once the process starts, she expects all the babies to hatch over the course of a few days. They’ll be about three centimeters at birth.
Once the young sea dragons are born, they’ll be moved behind the scenes to ensure they get enough food. They would most likely get lost if left on exhibit. Then, if all goes well, they’ll come back on exhibit after four to six months.
A Learning Experience
Raising tiny sea dragons is a fine art, and Jonelle stresses that there are a lot of things that could go wrong. “There’s a high probability that some of the eggs will drop off the male’s tail or that babies will be born not fully developed,” she says. “We don’t expect all the eggs to be there after five weeks.
“We’re really excited to have come this far, but we’re taking it day to day. The fact that this happened means that our sea dragons are doing well. But it’s a learning experience. We hoped this would happen, but we were still caught off guard when it actually did!”