Searching for dolphins

BLOG: DAY EIGHT

By: Rochelle Constantine

Latitude: 29o14 South
Longitude: 177o54.0 West
Wind Speed: Light
At anchor, off Raoul
Sea State: 1

Cloud Cover: 9 octaves

I have been waiting a while for today. I went up to the bridge, picked up my binoculars and the first thing I saw was a juvenile humpback whale.

It was travelling slowly from its northern breeding grounds, making its way over the next several weeks to the Antarctic feeding grounds after many months without food.

While everyone else ran up the stairs to see the whale passing very close by the ship, I grabbed my camera case and biopsy rifle from the ship’s armoury, met the rest of the crew and we were off to try and photograph and sample the whale.

I’m interested in these whales because I am part of a long-term collaborative research effort by the South Pacific Whale Research Consortium trying to understand the lives of these endangered humpbacks.

My research at the University of Auckland has evolved to include the Antarctic end of these whales’ lives and we are now curious about where they go to feed – it’s possibly in the remote Bellingshausen Sea area. If so, this might explain why the population is recovering so slowly. To answer this question, we plan to attach satellite tags to humpbacks here at Raoul when migrating whale sightings peak from September to November.

We briefly returned to the ship in the RHIB, picked up a load of students and Andrew from the LEARNZ team and went out find New Zealand’s northernmost population of bottlenose dolphins. We know nothing about these dolphins and finding them was a challenge.

Ironically, the first thing we saw when we dropped anchor several sleeps ago was a small group of five bottlenose dolphins. Since then we have only seen one other group in a 2m swell in Denham Bay. This was to the delight of the students, but to my disappointment the dolphins disappeared too quickly, without a single sample taken.

Today we found a group of nine dolphins and managed to get a perfect tissue sample to add to our other sample from last year.

The students were in charge of keeping an eye on the elusive animals and did a great job.

We all returned happy, especially me, and now we have another small piece of information to help us understand our bottlenose dolphins.

ABOUT ROCHELLE CONSTANTINE – Expedition Team Leader

Rochelle is a Senior Lecturer at the University of Auckland where her research is primarily on the behavioural ecology and conservation biology of cetaceans. In particular she likes integrating different research techniques to answer questions about the marine environment, threats to cetaceans and solutions to anthropogenic impacts.

She currently runs projects on Oceania's humpback whales, Bryde's whales in the Hauraki Gulf, bottlenose dolphins and Maui's dolphins.

Rochelle also curates one of the world's largest cetacean tissue archives from stranded and biopsied cetaceans. Her research on ship-strike, tourism impacts and population recovery is successful because of collaboration with many other researchers; many of whom she will be visiting over the coming months as part of my Fulbright Scholarship.

Rochelle's interest in the Kermadec Islands is to sample the bottlenose dolphins believed to be resident in around Raoul and to hopefully see humpback whales on their southern migration past the islands.

As part of the Southern Ocean Research Partnership (a non-lethal whale research programme) along with the South Pacific Whale research Consortium, they hope to tag whales at Raoul in 2013 to ascertain where their feeding grounds are.