Numbers down as Causeway works drive endangered whales away

RARE SIGHT in 2021: A whale breaching during past whale seasons. Photography by Nikki, via Encounter Whales facebook.
RARE SIGHT in 2021: A whale breaching during past whale seasons. Photography by Nikki, via Encounter Whales facebook.

The Conservation Council of SA and the Wilderness Society SA are calling for greater protection for endangered whales near Granite Island, as a scientific study reveals low whale numbers in Encounter Bay as noisy construction activity progressed during the whale season, despite a bumper year elsewhere in the state.

The new $43 million Causeway was officially opened in December.

The preliminary report from the Encounter Bay Right Whale Study (EBRWS) states that lower numbers of whale mothers and babies in Encounter Bay this year goes against the trend of previous years.

Only three female and calf pairs were resident for the season, with these pairs mainly sticking to the eastern end of the bay, well away from the Granite Island works. A further two mother and calf pairs arrived, but quickly departed, one of which fled with her newborn to lower Eyre Peninsula where they spent the remainder of the season.

Whales have made the south coast its adventure playground between May and October in past years.

Whales have made the south coast its adventure playground between May and October in past years.

This is despite 2021 representing the largest cohort of breeding Southern Right Whale females seen along the SA coastline, with numbers well up in other whale nurseries including the Head of Bight and Fowlers Bay.

"This preliminary study is clear evidence that the noisy and intrusive causeway construction works affected whale behaviour and drove whales away from Encounter Bay," Conservation SA Chief Executive Craig Wilkins said.

"While other parts of the SA and Victoria coastline had bumper years with high numbers of whale mothers and babies sighted, numbers were well down in Encounter Bay.

"At the time, we slammed the deeply irresponsible decision to proceed with the upgrade of the Granite Island Causeway during the peak whale breeding season because we feared the noisy pile driving would drive endangered whales away from our shores.

"It's incredibly frustrating and disappointing that our fears proved correct. Highly intrusive construction works must never again be permitted in a sensitive whale nursery during breeding season.

"There was a bumper year everywhere else along the SA coast with much higher whale visits than normal. So, we would normally expect numbers to be higher in Encounter Bay as well. But they weren't," Mr Wilkins said.

The Encounter Bay Right Whale Study is a collaborative research project established in 2013.

Collaborators include Flinders University, Curtin University, the South Australian Museum, the Department for Environment and Water and citizen scientists. Their 2021 Field Summary Interim Report is entitled 'Assessing the effects to southern right whales from construction activities associated with the Granite Island Causeway in Encounter Bay'.

The Federal and State Governments approved pile driving and construction of the new Granite Island Causeway inside the Encounter Bay southern right whale nursery site during the peak whale season this year.

"It's a special gift that endangered southern right whales choose to spend the winter in Encounter Bay," Wilderness Society SA Director Peter Owen said.

"We have an enormous responsibility to provide a safe haven for these magnificent creatures while they are in our waters.

"To progress the Granite Island causeway works during the sensitive whale breeding season was deeply irresponsible and because whale mothers tend to return to the same location to give birth, there is a strong possibility it will affect numbers in future years.

"Studies from Victoria show that every whale that stays close to shore brings in excess of a $1 million boost to the local economy through land-based whale watching tourism. Risking this vital tourism activity makes no sense.

"It's time for greater protection of the Encounter Bay whale aggregation area. The sensitive calving and nursery area in particular needs more focused protections, including a permanent exclusion of industrial activity, as well as other human disturbances such as speed, noise and approach of noisy motorised vessels." he said.

This story Whale numbers down due to works first appeared on The Times.