The devastating deaths of five little penguins on Granite Island in one week are believed to have been caused by a fox.
Lower Inman Valley man Stephen Hedges, who monitors the island's little penguin colony for Flinders University studies, has been voluntarily keeping an eye on the population since penguin tours stopped due to the coronavirus.
He was first alerted to a little penguin death when the first body was found by a Victor Harbor Horse Tram staff member on Wednesday morning, June 24. Two more bodies were found between Wednesday and Thursday.
Mr Hedges, a past tour guide, said only three penguins were seen during his evening monitoring on Thursday, when normally he could spot about a dozen - and on Friday he located a fourth and fifth body.
He said he spotted the fox himself while on the island with another volunteer, so he knew it was there.
"I saw the fox with a penguin, it dropped the penguin in front of me and another guide," he said.
"I saw it flopping on the ground and the fox next to it, then the fox ran off."
The little penguin bodies were found on lawns and gardens and near burrows on the island, further indicating they were killed by the fox and not a seal.
A Department for Environment and Water (DEW) spokesperson confirmed at least three of the deceased penguins had injuries "consistent with a fox attack", while the other two are still being examined.
They said bait and cage traps were laid to catch the fox, to no avail as yet.
"National Parks and Wildlife Service SA rangers placed fox baits and traps on Granite Island on Thursday after receiving reports on Wednesday night of a fox having taken little penguins on the island," the spokesperson said.
"Rangers attended the island on Wednesday night in an attempt to locate and remove the fox, but it could not be found."
National Parks and Wildlife Service (NPWS) SA Victor Harbor senior ranger Seiji Iwao said he and another ranger had patrolled the island for five days and nights from Wednesday night and had not located the fox.
Last night I saw a Granite Island little penguin for the first time! It’s been at the top of my bucket list since I moved here. Grateful that local guide Gael took me out while she checked burrows. Grave concerns for colony after a fox got onto island, leaving 5 dead @VictorTimespic.twitter.com/h2G4HZDUVc— Dani Brown (@itsdanibrown) July 1, 2020
But Mr Iwao said a Canid Pest Ejector, a spring-activated device which baits foxes and sprays poison in their mouths, had been installed on the island and had since been "activated".
He believed the fox responsible for the attacks had ingested the poison and most likely died.
Although the body has not been found, there have been no more animal deaths reported from Saturday onward and he had not seen any fresh fox paw prints on the island.
"After the ejector was activated, it would've killed the fox," he said.
"The baiting will be there for another month, but we are monitoring the situation."
Mr Iwao said NPWS SA acted as fast as it could, with other stakeholders including Mr Hedges, to remove the fox to reduce its impact.
"The penguin population is quite low on the island. The wildlife is an important asset to the park and we need to protect them," he said.
He said along with the penguin bodies, he had also found a deceased pigeon which appeared to have been attacked by a fox.
Mr Iwao said NPWS SA was investigating preventative measures to stop any more foxes returning to Granite Island, including a sonic repellent device.
The little penguin population has sat at about 30 birds since 2012, so if all five deceased penguins were from Granite Island, it would mean about one-sixth of the colony was now gone.
Flinders University penguin ecologist Diane Colombelli-Negrel said these deaths were even more devastating as it is currently breeding season.
"Some of the birds were showing mating and nesting behaviour," she said.
"We had some highly active mating birds ... one breeding pair that was highly productive in the last year is gone.
"It's too early to see the height of the impact this is going to have (on the population)."
Dr Colombelli-Negrel said although there had not been a fox on the island in a long time, it was an issue she was "constantly worried about".
She said because the little penguins are highly adapted to marine life, they struggle to run and have no defence and predation on land could be "catastrophic".
Mr Hedges is unsure whether there are more bodies yet to be found and is concerned the colony has been lost.
He said the loss was heart-breaking, especially as there were no other little penguin colonies on the Fleurieu Peninsula.
"There are tears, there is frustration, there's a bit of anger," he said.
"I think to myself that we've let this happen because we haven't done anything.
"Nobody took our advice to close the Causeway at night."
This is not the first time a fox has been on the island and killed little penguins.
In 2006, a fox killed 19 birds before it was killed with bait and in 1994 when there was a larger population, 74 penguins were killed by one fox.
The areas around burrows were patrolled as penguins returned each evening and the volunteer guides continued to monitor the colony.
While dogs are not permitted on the island at any time of year, DEW urged people not to take their pets to the island as the baits that have been laid were "highly poisonous" for dogs.