Whale Strandings: What you need to know

Source: NZ Department of Conservation

Summer’s here, and with more of us heading to the beach and along the coast for some much needed ‘naturing’ downtime, we thought it would be a good opportunity to talk about whale strandings – something that may occur over summer and something that we should all be aware of.

We’re sharing what causes whale strandings, what to do if you come across a stranded whale, and the important role Aotearoa New Zealand plays in protecting marine mammals.

We put together responses from some of the most frequently asked questions about whale strandings, to help people during the summer season if we have whales stranding.

Why do they strand?

Whale strandings are natural phenomena that have occurred for many years. – Since 1840 we’ve had more than 5,000 strandings recorded around the New Zealand Coast. We usually don’t know why they happen, but theories include:

• Illness or injury.
• Navigational and hunting errors, and predator avoidance
• Extreme weather or changes in water currents.
• Noise pollution or disorientation caused by human activities.

How common are whale strandings in New Zealand?

New Zealand is known as the global hotspot for whale strandings, having one of the highest rates of whale strandings in the world, responding to around 85 marine mammal stranding incidents each year, most involving just one or two animals. Mass strandings, events involving large groups, are less common but tend to occur with oceanic species like pilot whales.

Not all incidents are live strandings, most incidents that we respond to are of whales or dolphins that are already deceased. These are really important opportunities to learn more about these animals, so please report them promptly.

Between January 1, 2023, and May 23, 2024, there were 151 marine mammal stranding events involving 527 animals across our (DOC’s) 35 coastal districts. Of these, 63 individual animals were removed or buried following. Additionally, 27 animals were successfully refloated.

What are some notable whale strandings in New Zealand?

The largest recorded stranding was in 1918 on the Chatham Islands, involving about 1,000 pilot whales.

In 2024, 600 pilot whales stranded on Farewell Spit.

Which species strand most often?

Dolphins, pygmy sperm whales, and beaked whales are the most frequently stranded marine mammals.

Large whales, like sperm whales, also occasionally strand.

What should I do if I find a stranded whale?

1. Keep your distance Until you are advised what to do – prioritise the health and safety of yourself and others.
2. Keep animals calm – avoid loud noises, keep dogs and small children away.
3. Call 0800 DOC HOT or Project Jonah (0800 4 WHALE) immediately to report the stranding.
4. Follow DOC or Project Jonah’s instructions.

Who helps rescue stranded whales?

New Zealand is recognized as a world leader in successful whale rescues, thanks to:

• The partnership between DOC and Project Jonah.
• Support from iwi, local communities, volunteers, and other marine mammal rescue groups.

Are there any positive outcomes from stranding?

While strandings can be distressing, they also provide valuable opportunities for:

• Scientific research to learn more about marine mammals, understand environmental pressures, like climate change and pollution.
• Community involvement in conservation efforts.

Why is New Zealand a hotspot for strandings?

New Zealand’s location, surrounded by vast oceanic waters and its unique coastal geography, makes it a hotspot for marine mammal activity—and unfortunately, strandings.

For more information, visit our website or contact Project Jonah. Remember, the experts are there to assist both the whales and the public!

MIL OSI