Pet owners across the New South Wales far south coast have been placed on alert following the sudden beaching of toxic sea hares capable of causing severe poisoning in domestic animals.
The mysterious, gelatinous organisms were spotted scattered along tidelines by coastal residents in recent days, prompting concern among community members who initially mistook them for jellyfish or degraded cephalopods, ABC News NSW reported. Subsequent examination by marine specialists confirmed the creatures to be sea hares—a genus of large marine gastropod molluscs that inhabit coastal rock pools, reefs, and seagrass meadows.
Marine Slug Identified Behind Coastline Influx
While living sea hares play a harmless, vital role in benthic ecosystems by grazing on marine vegetation, their presence on the sand presents an acute hazard. Characterised by their soft, mottled bodies and two prominent sensory tentacles that resemble rabbit ears, the animals can grow to more than 20 centimetres in length.
When threatened or dying, sea hares can discharge a pungent purplish dye to deter predators. More critically, their tissues contain concentrated chemical defences—including aplysiatoxin—which they accumulate directly from the red and brown algae comprising their natural diet. These compounds do not break down quickly after the mollusc dies and washes ashore, rendering the carcasses dangerously potent even when dried out on the strandline.
Lethal Threat Posed to Coastal Canines
For curious canines traversing the sand, the beached molluscs pose a significant and potentially fatal attraction. Dogs are naturally drawn to the pungent odour of decaying marine life, and veterinarians warn that ingesting even a small fragment of a sea hare can trigger rapid, catastrophic toxicity.
Clinical signs of sea hare poisoning in dogs can manifest within minutes to a few hours of contact. Initial symptoms typically include excessive drooling, lethargy, and persistent vomiting, which can escalate swiftly into severe neurological disturbances. Affected animals often suffer muscle tremors, ataxia—a loss of bodily coordination resembling drunkenness—and violent seizures. In severe cases, the neurotoxins depress the respiratory system, leading to cardiac arrest or death if clinical treatment is not administered immediately.
Veterinary Guidance and Prevention
Veterinary practitioners across regional coastal hubs advise pet owners to remain vigilant while walking their dogs along affected beaches. Because there is no specific antidote for the marine toxin, treatment relies on aggressive supportive care. Standard clinical procedures involve inducing emesis if ingestion occurred recently, administering activated charcoal to bind remaining toxins, and managing tremors with muscle relaxants and intravenous fluids.
Beachgoers who suspect their pet has ingested or mouthed a sea hare are urged to treat the situation as a medical emergency and transport the animal to the nearest veterinary hospital without delay.
Annual Winds Bring Mass Strandings
Mass strandings of sea hares are not entirely unprecedented along the eastern seaboard of Australia. Marine biologists observe that these episodes frequently coincide with post-spawning mortality, rough coastal seas, and persistent onshore winds that dislodge the slow-moving creatures from their sub-tidal habitats and deposit them onto exposed sand.
Authorities and local wildlife groups advise the public to leave the creatures undisturbed, refrain from handling them with bare hands, and exercise heightened caution by keeping dogs on leashes near the high-tide line until conditions clear.