Current Projects on White's Seahorse

Seahorse hotels and captive breeding program

After dramatic reductions in population numbers over the past decade, a collaborative project is underway in Sydney Harbour to reverse the decline of White’s Seahorse. Also known as the Sydney Seahorse, this iconic seahorse was recently listed as ‘Endangered’ in NSW, making it Australia’s only threatened seahorse species and the second worldwide.

In an effort to recover dwindling numbers, NSW Department of Primary Industries Fisheries (DPI) partnered with SEA LIFE Sydney Aquarium, University of Technology Sydney (UTS), Sydney’s Indigenous Gamay Sea Rangers and Transport NSW and commenced a world-first conservation project.

Baby White's seahorse in SEA LIFE Sydney Aquarium

Successfully collecting and breeding the seahorses marked the first stage of the project. In October 2019, five breeding pairs, including pregnant males were collected from Clifton Gardens swimming net and taken to a custom-built breeding facility at SEA LIFE Sydney Aquarium. Dozens of juvenile White’s Seahorse were successfully bred and these baby seahorses (fry) thrived.

SEA LIFE Sydney Aquarium staff and volunteer constructing a seahorse hotel

In March 2020, the second ‘habitat’ stage was launched when nine ‘Seahorse Hotels’ were installed on the seafloor at Clifton Gardens. These novel artificial habitats were constructed by the team with help from SEA LIFE Ocean Youth Team. Inspired by lost crab traps that were previously identified as providing ideal habitat for seahorses, the purpose-built seahorse hotels have a major point of difference in that they are completely biodegradable. Designed to simulate natural seahorse habitats which have been lost, the hotels start as artificial habitats, but are rapidly encrusted by algae, sponges and coral once placed in the marine environment. Over time, the weight of this marine growth causes the artificial structure to collapse leaving a new natural habitat behind and perfect homes for seahorses.

DPI Fisheries and SEA LIFE Aquarium staff and Indigenous Gamay Rangers with the seahorse hotels (Photo: SEA LIFE Sydney Aquarium)

The seahorse hotels are ferried across Sydney Harbour by the Indigenous Gamay Rangers (Photo J. Keating)

Two months later the juveniles were big enough to be tagged and released onto their new five-star hotels as well as protective swimming nets in the Harbour. An important monitoring program has been implemented by the team to assess their growth, survival and breeding, and has yielded impressive results so far. Surveys conducted in November 2020 revealed that some of the captive bred juveniles are now pregnant with fry of their own.

DPI Fisheries, SEALIFE Sydney Aquarium staff and UTS students holding plastic bags containing juvenile White's seahorses prior to their release into Sydney Habour

The second year of captive breeding has also commenced with an additional 10 adults collected from Clifton Gardens to supplement the adults held at Sydney Aquarium. The plan is to breed up more fry then release these onto new hotels at Fairlight early next year, adjacent to Posidonia seagrass beds. This will provide more insight into how seahorse hotels, as a conservation tool, can help the recovery of White’s Seahorse.

Two tagged juvenile White's seahorses living on a seahorse hotel covered in macroalgae

Expansion of the hotels and breeding program

2021 saw a busy year for the White’s Seahorse, with the roll out of more hotels in Sydney Harbour and the release of over 140 new babies. In June, 18 new Seahorse Hotels were deployed, marking a major milestone for the seahorse team as these new additions tripled the number of Seahorse Hotels in Sydney Harbour.

In September, over 140 aquarium-bred baby White’s Seahorses were released into the wild, onto the newly established hotels. The hotels provide vital housing for the latest colony of seahorses, in a bid to recover their population in Sydney Harbour.

This breeding and recovery project is a collaborative effort between SEA LIFE Sydney Aquarium, DPI Fisheries, Ocean Youth, the Gamay Rangers, the University of Technology Sydney (UTS), the Sydney Institute of Marine Science(SIMS), generous support from Taylors Wines and all those who support the campaign.

A baby White's Seahorse released onto one of the new hotels in Sydney Harbour

More information

See White’s Seahorse for more information about the species.

Watch a video on the White’s Seahorse Recovery Project DPI is working on in collaboration with SEA LIFE Sydney Aquarium, University of Technology Sydney and the Indigenous Gamay Rangers (3:04 mins)

Watch the next instalment of the project – Five star ‘seahorse hotels’ installed in Sydney Harbour  (1:14 mins)

Watch White's Seahorses being released into Sydney Harbour after hugely successful breeding program (1:40 mins)

Watch a video of baby White's Seahorses born in captivity (0:26 mins)