Thursday, August 4, 2011

Fins, Flukes & Photographs - Fingerprinting Humpback Whales

A humpback whale calf breaches in the protected waters of Exmouth Gulf, Western Australia.

Next month Pam and I will haul our 6.3 metre Gemini Inflatable 1300 kilometres up the North Western Coastal Highway to Exmouth to photograph the 2011 humpback whale migration and hopefully add another 400 or so whales to the identification catalogue.  Each fluke and dorsal fin is different and a unique 'fingerprint' for that whale.

In 2010 we travelled 671 NM on the water and observed 526 whales in 215 pods.  After allowing for  known re-sights, we saw 483 whales and photographed 444 of them.  164 were new season calves.  

We have been travelling to Exmouth each year since 2006.  Our first trip was to SCUBA dive and we accidentally stumbled across the best place on the planet to photograph humpback whales - Exmouth Gulf.

From August through to October each year the gulf fills with humpbacks on the southern leg of their migration from the Kimberley to Antarctic waters.  They have travelled 1200 kilometres from the Kimberley birthing grounds and calves are about 4 weeks old. The mothers and calves tend to congregate along the western shoreline from Bundegi Reef past the marina, along Pebble Beach and further south.

The shallow north facing waters of Exmouth Gulf provide an ideal rest and respite sanctuary for the world's largest population of humpback whales.  Here the calves can rest and build endurance before the arduous journey ahead.

Ningaloo Reef sits just around the corner from Exmouth Gulf.  Its inclusion in June 2011 as a World Heritage Area was well deserved but the critical resting areas in Exmouth Gulf were excluded.

New Humpback Babies

The new birthing season for Western Australia's humpback whales is up and running.  These images of a mother and new born calf were taken from The Centre for Whale Research (Western Australia) vessel 'Whalesong.'

Whalesong is a new ice capable vessel recently acquired by CWR (WA) and ironically was operating just offshore from the abandoned whaling station Norwegian Bay towards the southern end of Western Australia's Ningaloo Reef.  Just as it was when whalers operated from this station, it is an ideal location to observe humpbacks on both the northern and southern legs of their annual migration.

Most humpback calves are born 1200 km further north in the warmer waters of the Kimberley and scientists are concerned that these births may be occurring too early in the migration cycle and incur high mortalities.

In the last few weeks two calves have had to be euthanised after becoming separated from their mothers in Ningaloo's shallow lagoons. Orcas (killer whales) have attacked and taken two other calves. It's a wild ride for the newborns and a sad end for some.