Massey University students have arrived at Farewell Spit to begin taking samples from dead whales to better understand what might have caused the stranding.
Massey University researcher Emma Betty said the samples would show the ages of the whales and the maturity of the pod.
"We're trying to get a good idea of what the composition is of the pods that strand and if that potentially is changing over time, or if we're getting consistently the same composition of pods," she said.
Ms Betty said the sampling wouldn't be able to determine exactly what caused this stranding.
Instead the researchers are hoping to understand more about the life history of the whales.
"We've been looking at some stomach content so it's more learning about the biology of the whales and what we can learn about the species," Ms Betty said.
Ms Betty said determining the cause of a stranding was like "looking for a needle in a haystack".
"We're just trying to learn more about the population so we can actually work out how these strandings are impacting the population."