Encounter Bay Whales May Be Escaping Construction Noise From Granite Island Causeway

Construction noise from pile drilling for the new Granite Island causeway is driving mother whales away during birthing season, conservationists say. Clare Peddie Climate & Environment Editor

A southern right whale has returned back to the sea after a brief stay in Wallace Lake on the New South Wales Mid North Coast.WHALE watchers and conservationists fear noise from the construction of the new Granite Island causeway is disrupting mothers and calves during birthing season.

Having campaigned unsuccessfully to shift the project’s timing in advance, the state’s peak environment body is now calling for an immediate stop to pile driving and other noisy construction activity at the Granite Island causeway while endangered southern right whales and their babies are in the vicinity.

Conservation SA chief executive Craig Wilkins said the current situation at Victor Harbor was a “dangerous experiment”.

“Never before in Australia has there been such invasive and disturbing activity allowed in a Biologically Important Area during the breeding time for an endangered species,” he said.

“We know that whales are incredibly sensitive to noise – they communicate with each other over many kilometres. We also know that noise travels far further under water than in the air.

“Residents in Victor Harbor can hear the pile driving activity in their homes kilometres away from the causeway construction site. So, heaven help any whales that happen to be nearby or approaching Encounter Bay at the time.”

Respect marine mammals and help keep them safe. Always keep at least 100m away from a whale, or 50m from a dolphin. Special restrictions apply when a calf is present.

Encounter Bay’s first mother and calf of the season were recorded about one kilometre off Basham Beach, then Frenchmen Rock, Port Elliot last Thursday, July 1. The pair were later observed the following day (Friday, July 2) out from Yilki between Granite Island and Wright Island, near the causeway. This forced the construction company to stop their works.

On Saturday morning, pile driving recommenced and that pair of whales hasn’t been seen since.

On Tuesday at 11.40am, another pair of southern right whales were spotted off Encounter Bay near West Island, travelling east.

A humpback whale was seen between The Bluff and Wright Island at 12.15pm.

The Southern Right Whale mother and calf at Christies Beach on Sunday July stayed close to shore and crowds gathered to watch. Picture: Selina Guckenbiehl

Another whale mother known as ‘Broderie’ arrived in the whale nursery mid-June but has not been seen for two weeks.

During a previous visit, Broderie stayed for 90 days in the nursery – offering a wonderful opportunity for land-based whale watchers, Mr Wilkins said.

“We know from economic studies that each whale that comes and stays in a whale watching area produces about $1 million in visitor tourism income,” he said.

Local whale observers have become increasingly concerned that whale behaviour has changed since pile driving commenced.

“Allowing noisy construction in Victor Harbor during the whale breeding season is like a hospital allowing jackhammers to be working within a maternity ward,” Mr Wilkins said.

“It’s outrageous and deeply disappointing this is going on. These magnificent wild creatures deserve better.”

Meanwhile a mother and calf was reported at Maslin Beach, 100m from Gull Rock at 9.37am on Tuesday.

Whale watchers have enjoyed sightings at Christies Beach and Port Noarlunga over recent days.

However the appearance of these whales at metropolitan beaches may indicate they want to escape the noise at Encounter Bay.

Construction on the new Granite Island causeway in Victor Harbor during March. Picture: Tom Huntley

Elizabeth Steele-Collins of Encounter Whales suspects the mother of the calf born at Christies Beach was trying to get to the next whale nursery and got “caught short”, like a mother forced to have her baby in the car on the way to the hospital.

“It is certainly possible that due to the pile driving and other noisy construction works that are currently happening with the Granite Island Causeway that whales are leaving, and some could even be bypassing the area altogether,” she said.

The Infrastructure and Transport Department has established protocols during piling works to mitigate potential noise impacts during the construction of the new Granite Island Causeway.

The team from The Encounter Bay Right Whale Study continues to document the individual whales and record their movements and behaviours and liaise with the Granite Island Causeway project team to report whale sightings.

Team leader Dr Claire Charlton from the Centre for Marine Science and Technology at Curtin University said it was just the beginning of the study and therefore too early to notice any trends