Over 300 baby White’s seahorses have been released into the waters off the Australian coast in an effort to save the country’s only endangered seahorse.
The White’s seahorse, endemic to the east coast of Australia, is a medium-sized species – for a seahorse. Their maximum size is only around 6 inches. That said, even the largest species in the world, the big-belly seahorse, rarely exceeds 11 inches.
The aquatic equine prefers shallow habitats and only ventures into depths of around 80 feet at the deepest. As a result, it has long been known as a common species in estuaries on the NSW coast. Sadly, however, its numbers have plummeted in recent years.
“Twenty years ago I could go diving here and I’d find 20 to 30 seahorses a dive,” diver and Department of Primary Industries scientist David Harasti explained to ABC. “But if I go there now I’d be lucky to find one or two.”
As with countless species of wildlife, both on land and under the sea, the decline of the White’s seahorse is largely due to human expansion and climate change. Coastal ecosystems are already fragile, and disturbances from human interaction have a devastating effect.
“Everything from boat moorings to coastal development, and any of the washout that comes during normal rains,” said Laura Simmons, Regional Curator for Australia and New Zealand Sea Life.
“The decline of the seahorses has been impacted greatly by the flooding that we’ve been having in New South Wales over the past few years.”
Baby White’s seahorses move into underwater ‘hotels’ to mature
To combat the dramatic loss in the White’s seahorse population, Sydney Aquarium launched a breeding program for them. After the gestation period, the males give birth to anywhere from 100-200 babies. The young seahorses then remain in captivity until reaching a safe size, at which point scientists release them into the sea.
The thought of hundreds of baby seahorses finding a new home in their natural habitat is pretty heartwarming. But it doesn’t end there. Once they reach the sea floor, they have actual homes there waiting for them.
More specifically, they have underwater “hotels” – metal structures designed to provide shelter for juvenile seahorses. Over time, the hotels accumulate algae, sponges, and coral. The finished product? The ideal habitat for a White’s seahorse.
After a massive multi-institute effort, we have 15 brand new seahorse hotels in Botany Bay. For the first time, wild and released White's Seahorse will be able to use Posidonia transplants along with the hotels as habitat pic.twitter.com/xXdhum31gl
— Operation Posidonia (@operationposid1) June 8, 2022
“That was the best one we’ve ever done. 350 baby seahorses sitting around in their new home,” Harasti said of the most recent release. “It’s great to see and I can’t wait to go back in a couple weeks and see how they’re doing.”
Now that the babies are safe in their hotels, scientists will monitor their survival and growth rates. Come October, the young White’s seahorses will be all grown up and ready to breed themselves.
