Hundreds of Christchurch residents gathered at Moncks Bay near Sumner this evening to watch the plight of a whale stranded on a sandbar.

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

The vessels were then revved loudly in an attempt scare the whale into freeing itself.

Those efforts were abandoned after 10 minutes.

At 9.35pm project Jonah staff and the coast guard withdrew to 150m away to reconsider plans.

Another attempt was made to motivate the whale to free itself shortly after with darkness falling.

However, the whale was still stuck as 10pm approached.