A whale stranded on a sandbar in Christchurch last night has died.

Hundreds of residents gathered as the whale struggled to free itself on Moncks Bay, near Sumner, yesterday evening.

Members of the Coastguard and Project Jonah arrived just after 9pm and approached the whale using a jet ski and a small inflatable craft.

Project Jonah coordinator Daren Grover told 1News this morning the animal was a juvenile fin whale.

The marine protection and rescue group will be working alongside the Department of Conservation and local iwi on a plan going forward.

The whale will be moved to a burial site at low tide, a Project Jonah spokesperson said.

It comes one week after a pod of more than 40 false killer whales and bottlenose dolphins were stranded on a reef near Māhia Peninsula.