Concerns for the survival of the Granite Island little penguin colony are growing as the population dwindles.
The current population is estimated at 20 penguins, and has fallen dramatically since 2001 when there were more than 1500 penguins on the island.
Chair of Save Granite Island Penguins and former City of Victor Harbor Mayor Graham Philp, has been proactive in advocating for a solution and said he was concerned for the survival of the colony.
"The aim is to find out if human interaction and recreational use has impacted the colony of penguins that inhabit Granite Island," Mr Philp said.
"The island has lost a large amount of penguin population over time. It is extremely sad to see a native animal's population decrease more and more every year.
"With a high volume of people filtering through, the penguins may avoid the area potentially limiting their access to food, shelter, and other resources. The penguins may also come across rubbish and try to eat it."
Over-fishing has also been raised as an issue, reducing the food sources of penguins and driving them away from the area.
At the start of 2020 at least 10 penguins were killed by foxes, another key concern. In 1994, a fox travelled to Granite Island and killed 54 penguins.
"This is why it is so important for the council to work with the managers of the island the Department of Environment and Water to erect gate to keep the foxes and dogs from crossing to the island over the causeway," Mr Philp said.
"Penguins have been killed and kicked around by cruel humans that disposed of them in the water as well."
Save Granite Island Penguins maintains a Facebook group to spread awareness and fundraise for preservation efforts such as supporting scientists to study the colony and its threats.
Recently, discussion on the group has turned to the planned construction of the new Granite Island Causeway, which is viewed as another serious threat to little penguins. The $31.1 million project to be delivered by the Department for Infrastructure and Transport (DIT) is expected to cover two penguin breeding seasons, which worries Mr Philp.
"The bridge being built could disrupt the penguin's habitat and lifestyle, which could lead to them not breeding in their normal cycle, or not breeding at all," he said.
"The building of the new and updated causeway will have a high chance of making the penguins extinct. Penguins need privacy to breed and if they are disturbed by humans for two years as well as big machines and noisy construction work, they will find it really hard to breed."
The causeway project is currently before the State Planning Commission (SCAP), with community information sessions planned for Friday, February 12. As part of DIT's application to SCAP, an Environment and Heritage Report addresses the potential impacts on marine life including little penguins.
"A recent census undertaken in October 2020 confirmed that the project footprint does not overlap with any active burrows," the report reads.
"It is however noted that the status of burrow activity can change and as such a pre-construction 'active penguin burrow' survey on Granite Island in the immediate vicinity of the project construction zone will be undertaken prior to commencement of works on the island."
Mr Philp remains concerned however and said pile driving specifically would have "a dramatic effect on the penguins that are left."
He said the little penguin colony was a very important part of South Australia due to it being the only place you can find them.
"The penguins are a big part of Granite Island and is one of the reasons people go there. If the penguins are wiped out, it would be very sad for South Australia to lose a species to extinction," Mr Philp said.
"There should be other plans and ideas to prevent the causeway from being built and disturbing the penguins or be postponed until they breed enough to have some sort of sustainability.
"Extinction could be prevented if better management strategies are put in place to minimise the negative impacts by recreational users and help build a sustainable future for the little penguins."