Tohorā sightings: giants of the ocean numbers are increasing

A tohora whale with her calf.

New Zealand's tohorā, or southern right whales, are considered a remarkable conservation story and as their numbers increase, these whales are returning to the waters around our mainland.

Southern right whales were hunted almost to extinction in the 1800s.

Whalers considered them the 'right' whale to hunt because they are slow moving and docile.

By 1920, there were thought to be only 40 whales from the original estimated population of 30,000.

An international hunting ban and establishment of a marine reserve in the Auckland Islands allowed the whales to recover to about 2000 whales by 2009.

The reserve provides a safe space for breeding and raising calves during winter which has been vital to their recovery.

Sightings from the mainland have become more common, such as Matariki, who captivated Wellington locals in 2018 with his acrobatics in the harbour.

However, little is known about where these gentle giants go outside their subantarctic refuge and how their migration is being affected by climate change.

To help boost this knowledge, scientists from the University of Auckland, in partnership with marine conservation charity Live Ocean, are asking the public to report sightings of southern right whales, and sightings of all other whales, to the Department of Conservation hotline 0800 DOCHOT (0800 362 468).

These sightings are likely to include southern right whales, humpback whales, blue whales and sperm whales which are the most common around mainland New Zealand in the winter months from June to October.

A Live Ocean information sheet is available to help people identify the type of whale they have seen.

The data from the public will help increase knowledge of whale distribution and movements around the country and bolster the satellite tracking programme, which will begin when researchers visit the Auckland Islands, which lie almost 500km south of the South island, in August this year.

Dr Emma Carroll, lead researcher from the University of Auckland and Rutherford Discovery Fellow, says: "Over the next few months southern right whales can literally be seen anywhere along Aotearoa New Zealand's coastline.

"Every sighting helps us understand what areas are important to the whales and how we could protect them in the future.

"We need the public to tell us what they're seeing out on the ocean."

A recently published pilot study involving researchers from across Australia and New Zealand showed two tracked whales went to the west of New Zealand up towards Australia, rather than to the east as expected.

This appears to be a startling change from the whaling era.

A key part of the campaign is how to record the details including the number of whales and calves, the direction they were travelling and how to take photographs or videos using identifying marks.

It also aims to educate the public on how to be whale-wise at sea.

How to be whale-wise at sea: Check your distance 
• keep 50m away (or 200m if the whale is with a calf)
• Keep a 'no wake' speed within 300m 
Check your position 
• Always come from a direction that is parallel and slightly from the rear
• Do not circle whales or obstruct their path
• Don't box whales in (against the shore or other boats)
• If a whale moves towards you, slow down and stop or carefully manoeuvre out of the whale's path
Be kind 
• Avoid loud or sudden noises 
• Never cut through a group or separate mothers from calves
• Don't feed or swim with whales