They returned home about 10pm and a Department of Conservation senior marine ranger went to the beach at first light today and discovered the dead whale.
Representatives of the local hāpu Patuharakeke will undertake flensing of the whale this afternoon and DoC senior marine ranger Cat Peters will also be present.
Patuharakeke has asked the public to give them space while the flensing is underway for health and safety purposes.
The whale will later be buried at a site away from the beach.
Project Jonah is asking locals in Ruakākā to keep an eye on beaches over the next few days and to report any marine mammals in distress to DoC on 0800 DOC HOT (0800 362 468) or Project Jonah on 0800 4 WHALE (0800 4 94253).