Latest news with #RowanCarew

9 News
19 hours ago
- Science
- 9 News
These seahorses started vanishing from Aussie waters. Here's why that's a problem
Your web browser is no longer supported. To improve your experience update it here Measuring about 15cm from top to tail, the endangered White's Seahorse is the kind of unique marine creature you have to look hard to find. Not just because they're tiny but because about 15 years ago, they started vanishing from Australian waters at alarming rates. A 2015 study revealed that some New South Wales populations were decimated by about 90 per cent in just five years. The White's Seahorse was declared endangered in 2020, yet there's still hardly any research on their populations in Queensland. (Supplied) And the same could be happening in Queensland, but scientists would never know it. There's currently no broad research about White's Seahorse populations in the sunshine state, meaning scientists have no baseline to measure current numbers against. That makes it difficult to track if these endangered seahorses are inching closer to extinction in Queensland waters, and limits the opportunity to introduce conservation measures that could save them. University of Queensland PhD candidate Rowan Carew intends to change that. Because if the White's Seahorse goes extinct, Australia's oceans will be in a dire state indeed. "Seahorses are what we call indicator species," Carew told Rowan Carew is on a mission to ensure the survival of the White's Seahorse in Queensland. (Supplied) "So if we lost our seahorse species in Queensland, that would indicate that the ecosystem or environment that they're in is unhealthy. "And that has a trickle down effect for all sorts of animals in these ecosystems ... so we definitely don't want to lose them." Research has shown that habitat loss and flood events had a devastating impact on NSW populations of White's Seahorse between 2009 and 2015. Carew fears the same may be happening to populations in Queensland, especially after years of floods and Cyclone Alfred at the start of 2025. "The main threat that we're looking at potentially is habitat loss," she said. "Things such as weather events like the recent cyclone, things such as dredging, things such as coastal development, that all impacts their habitat." But their habitat also makes White's Seahorses difficult to study in Queensland. Finding a White's Seahorse in Queensland can be like trying to find a needle in a haystack. (Supplied) In New South Wales, these seahorses tend to live around swim nets and soft coral colonies, making it easy for researchers to locate them in specific areas. Up north, they prefer to hang around in sea grass beds that can stretch for kilometers underwater, making these tiny critters much harder to find. "It's a little bit like looking for a needle in a haystack, which I think is why no one's really gone to a significant effort to do any research on them in Queensland," Carew said. The "only reason" her team is able to attempt it now is because they have the support of the Queensland Government and millions of potential citizen scientists. Researchers are calling on everyday Australians who spot a White's Seahorse in South-East Queensland while snorkelling or scuba diving to snap a photo and send it to them. Carew shows off a White's Seahorse she collected from a bed of sea grass. (Supplied) Not only will it allow them to collect additional data on individual seahorses, information sent in by citizen scientists may help them discover populations in unexpected locations. "Our team is very small, we can't get out into the whole of Moreton Bay and the Sunshine Coast and Gold Coast," Carew said. "So it's really important to have the citizen science, because that basically informs where we're going to do our surveys." There's something in it for the citizen scientists too. If your sighting leads the research team to a location where they find and tag a White's Seahorse, they'll name it after you and update you on its progress. Carew hopes that her research will help establish key information about White's Seahorse populations in Queensland and facilitate conservation efforts that could help get them taken off the endangered list. Citizen scientists who help researchers find and study these seahorses can get one named after them. (Supplied) Breed and release programs and installing artificial habitats have already boosted numbers in NSW, which is a promising start. "That's the main reason for this research and trying to push for conservation in Queensland," Carew said. "Because we just don't have any of those kind of measures in place to keep numbers stable if something does go wrong." national queensland nature ocean animals science CONTACT US

ABC News
3 days ago
- Science
- ABC News
University of Queensland researchers survey population of endangered White's Seahorse
Researchers hope a survey of endangered seahorse populations in Queensland waters will lead to a better understanding of a fish "very little" is known about. White's Seahorse is found in seagrass beds along Australia's east coast, and scientists say their presence can illustrate the health of marine ecosystems. The species grows to between 10 and 15 centimetres, and is considered endangered in New South Wales and Queensland, as well as at a federal level. Lead researcher and PhD candidate at the University of Queensland (UQ), Rowan Carew, said most of research on the the seahorse has been done in NSW. "In Queensland we really don't know how many there are, how they live, what kind of habitats they're on and what kind of threats they're facing," Ms Carew said. Associate Professor Karen Cheney from UQ's school of environment said research would mostly take place in Moreton Bay, where the Brisbane River met the sea, as well as on the Sunshine Coast and Gold Coast. "We keep seeing them, we know that they're here, we just don't know anything about their population structure, what type of habitat they like to live on, and we just don't know how many we've got," she said. Recorded sightings by citizen scientists have given researchers an understanding of where solid populations might be, but Ms Carew said it was difficult to establish how many seahorses there were because there was no "baseline". "In terms of future conservation, we are trying to figure out what areas are going to be the most important," she said. Ms Carew said seahorses were "really awesome, charismatic little fish" that were considered an "indicator species" for ecosystem health. White's Seahorse can alter their colour, both long-term for camouflage and in short fast patterns, which are part of their mating rituals. The seahorses are "relatively monogamous" and do a replication of their mating ritual every morning to "learn each other's movements", Ms Carew said. "They colour match and flash different colours when they do their mating dance in the morning," she said. Dr Cheney said the species — sometimes called the Sydney Seahorse — was listed as endangered in NSW in 2020 after research showed some populations declined by 90 per cent over six years. That research led to conservation projects aimed at seahorse habitat, as well as breed and release programs in Port Stephens and Sydney. She said "very little" was known of the fish in Queensland, and researchers needed more data before similar efforts could be replicated in the state. Ms Carew said it was not even known if the Queensland seahorses were "genetically the same as the seahorses in Sydney". She said genetic testing would be a part of the project she hoped would lead to more studies in Queensland.