A sperm whale that was stranded off Caroline Bay in Timaru for more than nine hours has started to swim "under its own power" following earnest efforts from rescuers.
According to the Department of Conservation, the whale came off the tension strap earlier on Sunday evening with the Coastguard then trying to shepherd it into deeper water.
While it is possible the whale could beach again, it is a step in the right direction.
Earlier on Sunday a digger was used to remove sand between the whale and the ocean to create a channel before the tide returned.
About 5.30pm, DOC's operations manager Duncan Toogood said the whale was in a much better position.
It was hoped it would refloat itself on the high tide at 9.30pm.
"In the meantime a fishing vessel is holding tension on a strap designed to come free if the whale swims away," Toogood said.
"It's now dark and everyone is out of the water, and there's not much more we can do."
Police will monitor the beach overnight with DOC returning at first light to check on the whale.
"DOC would like to thank Project Jonah, Timaru Prime Port and the keen volunteers who helped out today," Toogood said.
Speaking earlier on Sunday, Project Jonah general manager Daren Grover said early attempts to place a wide set rope around the body of the whale and attach the other end to a powerful fishing boat were unsuccessful in moving it into deeper water.
He said they halted that refloat plan when the tide became too low.
One onlooker took a video of the scene and tweeted: "My heart aches. Stranded whale here in Timaru. Waiting to be told what to do, may need all hands on deck team!"
Just three days ago a Bryde's whale was stranded at Whakatete Bay, north of Thames, but it died.
DoC staff shifted the whale from Whakatete Bay on Saturday and tried to bring it onshore to take it to a burial site, but weather conditions made it too difficult.
Staff were working again on Sunday to bring it on shore at high tide and are having more success, with a large number of spectators standing by.