A pod of pilot whales has become stranded in shallow waters at Farewell Spit as the tide has begun to fall, prompting an urgent response from the Department of Conservation and volunteers.

The Department of Conservation said it was alerted to the pod at about 11am and immediately deployed a boat and staff to the area.

A department spokesperson said staff, alongside Project Jonah New Zealand members and volunteers, had been standing in the water to help guide the whales away from the shallows while a boat monitored the pod’s movements offshore.

The spokesperson said tides had been favourable earlier in the day, but conditions had since changed, with some of the pilot whales beginning to strand as the tide went out.

It was too early to confirm how many whales were affected, the department said, with an accurate number expected once the tide reached its lowest point.

People would remain with the whales until dark, with teams returning at first light, the spokesperson said.

The department said Farewell Spit was a naturally occurring whale trap due to its geography and location along a migratory route for long finned pilot whales in New Zealand.

The long sandspit curves around the northern entrance to Golden Bay, creating extensive tidal flats and gently sloping waters that can mislead whales, particularly when the tide drops quickly.

Pilot whales are known for strong social bonds, and the department said when one whale enters shallow water, others in the pod often follow in an instinctive effort to stay together.

The Department of Conservation said it would continue to provide updates as the situation developed.