A pod of whales has been sighted near a recent stranding site in Tasman's Golden Bay.
Almost 40 pilot whales stranded on Farewell Spit on Monday, with several of them dying on the beach.
Nineteen whales were refloated on Wednesday.
Department of Conservation operations manager Ross Trotter said first light checks on Thursday morning found no whales.
However, whales have now been reported in the bay, close to shore.
There are no strandings at this stage, but rescue teams and a boat are headed to the area.
Rescuers say the next few hours will be critical for the pod.
Trotter says the pod is still swimming, although it was reasonably close to the shore in Collingwood.
"[We're] at high tide now, so the next few hours will be critical with the outgoing tide and risk of restranding."
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