Seals are frequent visitors to Sydney Harbour and occasionally Botany Bay, but they are not often seen in the highly urbanised and polluted Cooks River.
For the past week, Sydneysiders have been spotting a seal resting on the banks of the Cooks, as far upstream as Earlwood.
Craig Ryan, a spokesman for the Organisation for the Rescue and Research of Cetaceans in Australia (ORRCA), said members of the public first reported the seal a week ago. It had been spotted at Kyeemagh on the bay, Muddy Creek at the mouth of the river, and upstream at Wolli Creek and Earlwood.
“We’ve noted the condition of the seal is declining, but there’s no determination of the cause, and it hauls back in before we can get to it,” Ryan said. “We’re working with the National Parks and Wildlife Service to assess it.”
Ryan said members of the public should stay at least 40 metres away, keep dogs well clear, and report further sightings to the ORRCA 24/7 Rescue Hotline on (02) 9415 3333.
Based on photographs, the seal is a long-nosed fur seal – also called a New Zealand fur seal – while sex is yet to be determined.
Wildlife scientist Dr Vanessa Pirotta said the animal appeared “skeletal and probably unwell”, so members of the public should report any sightings to ORRCA but otherwise keep their distance.
Pirotta is the chief scientist for citizen science project Wild Sydney Harbour which, along with groups such as the Gamay Rangers, is trying to understand how seals use Sydney’s waterways.
The Cooks River seal was the same species as Benny and the other seals often seen resting on the VIP stairs at the Sydney Opera House. Pirotta said the long-nosed fur seals often swam up from Montague Island on the South Coast.
“It reminds us how we coexist with these creatures in the urban environment, but often we don’t see them,” Pirotta said.
“The most famous ones occupy the steps of the Opera House, but those are healthy animals resting between feeds.
Ryan said seals would sometimes travel up rivers either to rest or to find food, but it was unusual for the Cooks.
“I grew up on the Cooks River and the thought of having a seal in it is quite remarkable. But that said, it’s a lot cleaner than 20 years ago,” Ryan added.
Jason L’Ecuyer from the Cooks River Alliance said it was a positive sign to see life in the river, not only the seal but also mullet spawning, although the water quality continued to be poor.
“We’re not making a lot of gains in terms of improving water quality,” L’Ecuyer said. “If it’s gaunt, I would hope it’s coming up a healthy river for refuge, but that’s not the case.“
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Caitlin Fitzsimmons is the environment and climate reporter for The Sydney Morning Herald. She was previously the social affairs reporter and the Money editor.Connect via email.