10 Facts about Whales

Blue whale fluke
© Richard Barrett / WWF-UK
Fascinating Facts

Whales are the world's largest mammals. They roam throughout all of the world's oceans, communicating with complex sounds.

Here are some things you might not know about whales.

1.   Two types of whales 

Whales are divided into two groups: baleen whales that have baleen plates in their mouth, which they use to filter out and consume huge quantities of krill and plankton and toothed whales who have teeth which enable them to feed on larger species such as fish and squid.

2.   Dolphins are also whales

Dolphins and porpoises are considered toothed whales. The other species of toothed whales include the sperm whales, beaked whales and the unicorn of the sea, the narwhal.

3.   New Zealand whales

A number of whale species are found in New Zealand waters, some year-round, some, like humpback whales, just passing through on the annual migration between Antarctica and the tropics. Noted resident populations include Bryde’s whales in the Hauraki Gulf and sperm whales in Kaikoura.

4.   Unknown numbers

Most of the whale species found around New Zealand are listed on the Threat Classifications system as 'data deficient', meaning they are seldom seen, but not enough is known about them to determine how at risk they are. This includes the blue whales that spend part of each year off the coast of Taranaki. 

5.   Whaling

New Zealand would have more whales if we hadn’t been actively involved in commercial whaling from the 1820s. The last whaling station closed in 1964, mostly because we’d run out of whales. The practice didn’t become illegal until 1978. 

southern right whale and human diver
© Brian J. Skerry / National Geographic Stock / WWF

Southern right whale and diver

6.   Still whaling

A moratorium on commercial whale hunting was implemented by the International Whaling Commission (IWC) in 1986. Despite this three countries – Iceland, Japan and Norway – continue their commercial whaling with more than 1,000 whales a year killed for commercial purposes.

7.   The right whale

Southern right whale populations were deemed the “right” whales to catch and almost hunted to extinction. They are making a comeback with the New Zealand population growing and sightings around mainland New Zealand, including in Wellington Harbour becoming more common. In 2019 their threat status was changed from "Threatened – Nationally Vulnerable" to "At Risk – Recovering".

8.   Threats

While the end of most whale hunting has allowed some species like the southern right whale to recover, whales still face many threats. Notably bycatch, pollution, ship strike and underwater noise, habitat degradation and climate change. 

9.   Climate change impact

Antarctica and the Southern Ocean are important feeding grounds for the largest animal on Earth - the critical endangered Antarctic blue whale. Rising ocean temperatures and melting sea ice in the region poses a grave threat to krill - a key species in the Antarctic food web - and the whales that prey on them.

10.   Climate change solution

Whales, particularly the larger baleen species play a significant role in the carbon cycle. Not only do they sequester large amounts of carbon in their giant bodies, their presence or more specifically their excretions, boosts phytoplankton production. These tiny photosynthesisers capture an estimated 40% of all CO2 produced. Saving the whales could help save the planet from global warming.