Dense masses of krill have appeared along the coastline north of Wellington especially along Kāpiti beaches as well as Porirua's Pukerua Bay yesterday and today.
There was also a noticable smell from the dead krill.
Diane Cooper saw masses of the krill at Waikanae Beach.
"Obviously not a regular event as not a seagull in sight to enjoy the feast.
Department of Conservation marine ecosystems technical advisor Emma Hill said, "The volume of krill is likely due to a phyto-plankton bloom in the area, which in turn has created a bloom in zooplankton, which eat phyto-plankton, ie krill.
"There look to be several species involved, the most common one is probably nyctiphanes australis.
"The most likely explanation to them washing up onshore is due to heavy onshore winds or strong currents.