The Odyssey searching day and night for sperm whales 350 miles off the coast of Western Australia
Photo: Chris Johnson
May 19, 2002
Surveying the New Holland Grounds
This is Genevieve Johnson speaking to you from the Odyssey.
Since leaving Fremantle, we have been traveling northwest, on passage to the Cocos Keeling island group-27 idyllic specks of coral lost in the Indian Ocean, 1620 miles from Perth.
Our first 24 hours at sea were characterized by blue skies, a calm blue ocean, endless flotillas of blue bottle jelly fish (also called Portuguese Man O' War Jellies) and a Blue whale - our fifth sighting in Western Australian waters.
It appeared that good fortune was on our side, and before dawn on our second morning we had picked up a rowdy group of sperm whales just outside Australian territorial waters. The whales were clicking and making codas and as the weather held the favorable conditions enabled us to stay with this group of 12 -15 animals for 2 days collecting a lot of data.
Throughout this time, our lives were punctuated by the constant squeals, creaks and squeaks of pilot whales that were broadcast over the speakers aboard Odyssey along with the sounds of sperm whales. The pilot whales' sounds made a striking contrast to the slow, monotonous clicks of the foraging sperm whales.
Click here to listen the Pilot and Sperm Whales on the Odyssey underwater microphone - Real Audio required
Our encounters with pilot whales are usually fairly short lived, however on this occasion the whales remained in our immediate vicinity all day, and their attentions seemed to be focused entirely on the sperm whales. Whenever they surfaced, the pilot whales porpoised toward the sperm whales at high speed, circled them tightly, and swam directly in their wakes with their heads close to the trailing edges of the sperm whales' flukes. Were they simply 'playing', or was this some form of natural association we don't understand or perhaps aggression related to food competition? While we were still trying to find out, the wind abruptly picked up and we were forced to leave the group and continue our course North to the New Holland Grounds - (so named by the early Dutch whalers before the name "Australia" was officially adopted in 1829). We are currently searching for sperm whales here, because The Townsend Charts that show the distribution of whales based on catch records from early whalers, indicate that this area
was heavily exploited by Yankee Whalers in the 18th and 19th centuries between the months of April and July.
Sperm Whale slapping its tail.
Photo: Chris Johnson
Note: This photograph was taken under the authority of
Research Permit No. 751-1614, issued by the National Marine Fisheries
Service under the authority of the Marine Mammal Protection Act and the
Endangered Species Act.
The Wallaby Saddle, made up of two, large, underwater plateaus - Cuvier plateau and Zenith plateau, runs through the center of the New Holland Grounds. Each of these plateaus rises from the ocean floor for 5 kilometres to within about 1 ½ kilometres of the surface. The plateau walls plunge steeply into the ocean depths, dropping in some places for thousands of metres within a distance of one or two kilometres. We know from experience that bathymetric features such as these attract deep-water fish and squid which in turn attract the sperm whales.
We have been traversing the old whaling grounds for the past few days and have found a large, dispersed group of about 20 whales travelling west along the southern underwater escarpment of Cuvier Plateau. After spending yesterday collecting data from the group, we stopped at sundown in order to do some squid 'jigging'.
We jig for squid for three reasons-
- To help us identify the squid beaks we find in sperm whale fecal samples (we compare them to the beaks of the squid we catch in the same waters).
- In order to measure the levels of man made toxicants in the squid we catch (we look for correlation between pollutant levels in the squid and pollutant levels in the whales that are living in the same area.
- We also jig for squid because we are hoping to catch a fresh meal.
A low pressure front has descended upon us over night, the swell has risen significantly and we are experiencing wind gusts of up to 50 knots. We have left Cuvier Plateau and are now headed northwest toward Zenith Plateau, where we hope to cross paths with more sperm whales. For now, when not on watch, we crew members seek sanctuary in our cabins. Moving around the boat is difficult and is undertaken only at one's own risk. Oh how rapidly life changes at sea.
So stay tuned!
Log by Genevieve Johnson