Listening for Leviathans
Blogger: Forest & Bird’s Marine Advocate, Karen Baird
I’m part of a group of five scientists and conservationists departing Whangarei on ‘SV FalconGT’ this Sunday to listen out for whale chatter near the Kermadec trench – a deep trench to the far, far north-east of New Zealand.
Physically, the Kermadec trench is defined by an extensive, volcanic and highly active submarine arc extending from White Island to Tonga.
In the 1800s American whalers killed hauled in great numbers of sperm and right whales around this deep-sea trench and it is well-known migratory route for humpback whales, so it hoped the ocean will be alive with whale-conversation!
One species we’re especially interested in is a group of more enigmatic cetaceans – beaked whales.
As the name suggests these whales have a beak studded with small teeth – not too dissimilar to a dolphin. And in the males, they have a secondary set of teeth that protrudes from their bottom jaw – not too dissimilar to a deer’s antlers.
It is thought that these protruding teeth acts as both an identifier and a weapon – potential females mates will size up a male’s teeth to ensure they’re dealing with the right species and males will use these teeth in jousting competitions.
All of this is particularly speculative though because for the large part, these creatures have remained very much unstudied. Unlike other whales, beaked whales only surface for a short breather before returning to great depths to literally ‘suck back’ squid, crustaceans and fish.
So we’re going to spend the next two weeks bobbing on top of this almighty trench (it could sink Everest) and listening to whale speak using a hydrophone and specialised recorder.
And it is hoped that by listening out for the high frequency clicks of these elusive creatures we’ll be able to change the IUCN’s red list status of ‘data deficient’, and hopefully help to better define their conservation status.
If you’re interested in see some of the research that has been done on beaked whales, see this video here – http://www.whaletrackers.com/beaked-whales/
For more information on our trip keep your eyes on this website – http://www.thekermadecs.org/