Study sheds new light on whale movements

A photo-identification study of humpback whales has uncovered new evidence of the migratory movement of whales between the Antarctic, the east coast of Australia and the Oceania region, including New Zealand.

Two projects have been completed by members of the Southern Cross University Whale Research Centre, in collaboration with a number of other researchers who make up the South Pacific Whale Research Consortium.

The results were presented to the Scientific Committee of the International Whaling Commission.

Trish Franklin, a PhD student with Southern Cross University and co-director of The Oceania Project (Hervey Bay) said the photo-identification had yielded important information.

“This is a very critical step in gaining a broader insight into the migratory interaction within and between the feeding grounds in the Antarctic and among the migratory corridors and breedings grounds along the east coast of Australia and Oceania,” Ms Franklin said.

Over the last 20 years, Trish and partner Wally Franklin, also a PhD student, have collected more than 3000 photographs identifying individual whales.

The information they have collected, together with a catalogue from the migration of whales past Byron Bay and Ballina, has now been matched with much smaller catalogues from the Balleny Islands, Antarctica, and catalogues from Oceania – New Zealand, New Caledonia, Vanuatu, Fiji, Samoa, Tonga, Niue, Cook Islands, French Polynesia and American Samoa.

“We have had matches between Hervey Bay, Byron Bay, Ballina and the Antarctic, including the same individuals seen at Hervey Bay and Byron Bay, but in different years, that were then photographed in Antarctica,” Ms Franklin said.

“One whale was identified in the early part of the season near New Zealand and then in the later part of the season in Hervey Bay.

“The fact that they are moving between New Zealand and Hervey Bay within the same season is absolutely fascinating information. In terms of the science it reveals a relationship between New Zealand and east Australian whales that we didn’t know about previously.”

Migratory movements were also recorded between east Australia and New Caledonia and Tonga.

Ms Franklin said while the number of matches was relatively small, it was still significant as the catalogues for Oceania and Balleny were also quite small.

“These findings provide an incentive for us to get more data from the Antarctic. That is one of the big gaps in our knowledge,” she said.

“Having this information directly assists in identifying whether the whale populations are separate or combined management units, and that in turn helps us effectively manage those groups.

“We do suspect that a number of these populations, particularly in Oceania, are highly vulnerable.”

Professor Peter Baverstock, Pro Vice-Chancellor Research, said it was only possible to get this sort of information through the extensive collection of data.

“The chances of finding a match in such cases is only possible when one has a huge collection of identified whales. It is a huge tribute to the dedication of the Franklins to have amassed this huge collection of individually identified whales that now makes these matches feasible,” Professor Baverstock said.

Ms Franklin said she and Wally would be returning to Hervey Bay in the next month to continue their photo-identification work during their annual whale expeditions, run as part of The Oceania Project, a not-for-profit research and education organisation.

The expeditions are run for five days/six nights, over a period of 10 weeks, on board the 12-metre catamaran 'Moon Dancer' and are open to paying interns.

Photo: Norah, a humpback whale, was photographed in Hervey Bay by Trish Franklin on September 26, 2005. The whale was photographed again at Balleny Island on February 14, 2006 and at Byron Bay on July 6, 2004.

Media contact: Brigid Veale, Southern Cross University communications manager, 02 66593006 or 0439 680 748.