A massive landslide at Ohau Point in Kaikoura has wiped out a special seal sanctuary just weeks from breeding season.
The Department of Conservation (DoC) says it's not yet known how many seals have been killed, but some will have been out at sea foraging at the time of the earthquake.
DoC staff familiar with the area say aerial photos of the damage make it clear that the nursery for pups has been destroyed.
A dead fish is seen around the Ohau Point waterfall where seal pups used to shelter
The spot off State Highway 1 just outside Kaikoura is popular with tourists, with the waterfall and sanctuary just a few minutes' walk from the road.
DoC manager Ian Angus says there are still some areas to the north and south where the mammals can find refuge.
But the earthquake has had an effect on more than just the seals and the town's now world-famous cows.
DoC says the Hutton's shearwater, blue penguin and other bird species that live in the area also have been affected. Half of the largest Hutton shearwater colony has slipped away in a landslide caused by the quake, which DoC says a devastating loss for a species already considered at-risk.
Bees and wasps now occupy where the sea was once one to two metres deep
However, the department says its first and immediate priority is to help Civil Defence with the recovery effort, including making sure structures and tracks are safe.
"Seals and seabirds are often found breeding or resting in exposed areas, such as a cliff or seashore, and so may be prone to further slips or landslides. It will be important that the safety of the researchers can be ensured before visiting seal or seabird colonies."
Mr Angus says that means it could be weeks before a full assessment of the earthquake's impact on wildlife can be completed.