The Department for Environment and Water (DEW) has confirmed to The Times that an investigation is under way following a report that a boatie came too close to a whale mother and calf off Basham's Beach, on Sunday, September 15.
Adelaide based student Will Gilmore was whale watching last Sunday, when he witnessed a small boat approach a mother and calf pair, who had been "playing" in the Encounter Bay Restricted Area, approximately 200 metres from shore.
"The whales were just relaxing at the time and playing," he said.
"The boat came around from Port Elliot and then swung in towards the whales and hung around for about five to ten minutes."
The boat is then alleged to have made more than one close pass of the whale pair.
Under National Parks and Wildlife (Protected Animals - Marine Mammals) Regulations 2010 (SA), within the Encounter Bay Restricted Area all vessels engaged in observing marine mammals (motorised and non-motorised) must not move closer than 300 metres to a whale or calf.
Mr Gilmore said it appeared the boatie was aware of the whales.
"He was going towards the whale [mum] and then moving off a bit before coming back again, he probably did that once or twice.
"He definitely knew the whales were there. There was no way he didn't see them. The boat was directly facing the whales."
According to Mr Gilmore who photographed the incident, the boatie did not appear to abide by National Parks regulations.
"He didn't cut the engines or let the whales move on," said Mr Gilmore.
"There was no regard to the government regulations concerning approach distances to mums and calves, he just went straight for them.
"It looked like once he left the whales he went out deeper and anchored, so he may have been fishing, but he definitely didn't stop to fish close to shore, and his intention appeared to be to see the whales."
Mr Gilmore said the whale mother showed disturbed behaviour in the presence of the boat and left the area at speed.
"She moved very quickly, much more so than what she was before," he said.
"The whale did a complete 180 and swam off, she just took her calf in the opposite direction staying down [underwater] for quite a long time.
"I think I saw her surface once or twice before making it all the way over to Frenchman's Rock."
At the time of writing, the boat and owner are yet to be identified.