In “an extremely rare occurrence,” a pregnant male seadragon made history at a La Jolla aquarium.
The weedy seadragon’s pregnancy marks “the first successful transfer of eggs from a female seadragon to a male” at the Seadragons & Seahorses habitat at the Birch Aquarium at Scripps Institution of Oceanography at UC San Diego, a Jan. 9 news release from the aquarium said.
“We’re elated to be able to witness this at the aquarium,” Jenn Nero Moffatt, senior director of animal care, science and conservation, said in the release. “It’s extremely rare for seadragons to breed in captivity, so this is a monumental milestone for all of our staff.”
The habitat, which opened in 2019, was designed with breeding in mind, according to the aquarium. “We have been working with seadragons since 1996. Since then, we have learned so much about caring for these creatures and invested a lot in our breeding program,” Nero Moffatt said. “From the lighting to the rockwork; everything has been strategically designed with breeding seadragons in mind.”
Exciting News 🎉 Sometime overnight one of our female #WeedySeadragons transferred eggs to a male. While there is no guarantee that any #seadragon #eggs will hatch, we’re excited to share this milestone with you all! pic.twitter.com/DWNMAw6g0K
— Birch Aquarium (@Birch_Aquarium) January 9, 2023
Similar to seahorses, male seadragons carry the eggs until birth, the aquarium said. Though transferring the eggs from female to male is quick, it requires something unique — a “courtship dance,” according to the aquarium.
“The male and female mirror each other, often with their tails curled away from their mate, and spin together snout-to-snout moving up and down in the water column,” the aquarium said. “This dance is essential for the successful transfer of eggs from the female onto the male’s tail, where he then fertilizes and hosts the eggs.” For four to six weeks, the aquarium’s seadragon will keep the eggs on his tail “until they are ready to hatch,” the aquarium said.
During that time, the aquarium said they will be keeping a close eye on him.
“He is doing well and can be seen up close in Seadragons & Seahorses, though he might move behind the scenes closer to the hatching date,” according to the release. The aquarium said it only expects a “small percentage of eggs” to develop. This is the “first time a seadragon has laid eggs on the public side of the aquarium,” the release said.
In 2020, the aquarium had a seadragon lay eggs “behind the scenes,” which led to the birth of two weedy seadragons, the aquarium said, making it “one of only a handful of aquariums in the world to breed these mysterious animals.”
CHALLENGES IN THE WILD
Weedy seadragons are native to southern Australia, according to the release. They face a number of “challenges in the wild including climate change, warming oceans and compromised habitats.”
The species was listed as “near threatened” in 2006 by the International Union for the Conservation of Nature, according to Birch Aquarium. They have since been “downgraded to ‘least concern’ — partially because of the lack of population data.” “Their remote habitat along Australia’s rugged and underpopulated South Coast makes observation difficult,” according to the aquarium. Birch Aquarium studies the weedy seadragons in the wild and in captivity “to alleviate pressure on wild populations,” according to the aquarium.