Strandings education resource

Why do whales strand?

Whale strandings are complex events that involve various causes – anything from disease to extreme weather.

A stranded whale might be old or infested with parasites. It could have been poisoned by natural toxins or have had problems with giving birth.

Coastlines may play a part in whale strandings. Whales chasing prey near shallow sloping beaches can strand. They can also be trapped by receding tides. Some people have suggested that abnormalities in the Earth’s magnetic field may also cause strandings.

Human-made noise and pollution, accidents involving boats, and entanglements with fishing gear add to whales’ mortality rate

Find out more about whale strandings.

At the exhibition

Introduce students to this section about the reasons for whale strandings and human responses to them. Get the students to explore the immediate area then discuss the following questions and topics.

Questions for 5 to 10 year olds

•  How do whale strandings make you feel?
• Are there any images in this area that you like or dislike? Why is that?
• Why do whales strand?

Questions for 10 years old and over

• How do whale strandings make you feel?
• Are there any images in this area that you like or dislike? Why?
• Why do whales strand?
• Can you think of any other reasons for strandings?
• If you were on a beach and a whale stranded, what would you do?
• Find the Stranding Innovation Pontoon. Can you think of a way to save a  stranded whale?
• In what ways can pollution affect whale strandings?
• How might fishing have an impact on strandings?
• Should we save stranded whales?

Teachers notes:

Strandings can have a strong emotional effect on communities, impelling people to come together to try to rescue the whales.

Whales strand for many different reasons – parasites, pollution, disease, disorientation, accidents with boats, and entanglements with fishing gear. Even coastlines may play a part in strandings – whales chasing prey near shallow sloping beaches can become trapped by receding tides.

Once stranded, whales suffer internal damage and overheating, and deteriorate rapidly. Because of their size, they can be difficult and dangerous to refloat.

If refloating isn’t possible, the current thinking is to prevent the whales from suffering further. Humane killing methods have recently been devised for this purpose.

Stranded pilot whales on Okawa Beach, Chatham Islands, December 2005. Reproduced courtesy of Department of Conservation Te Papa Atawhai

Stranded humpback whale calf, Mason Bay, Stewart Island, October 2002. Reproduced courtesy of Department of Conservation Te Papa Atawhai

Girl pouring water over stranded pilot whale, Karikari Beach, 1997. Photograph by Dr Ingrid Visser, reproduced courtesy of Dr Ingrid Visser, Orca Research Trust

Stranded pilot whales on Ocean Beach, Stewart Island, January 2003. Photograph by Barry Harcourt, reproduced courtesy of The Southland Times.