In the Pacific Northwest, orcas that hunt marine mammals were first described as “transients”, as they were rarely seen, and thought to be just transiting through. They later became known as Bigg’s, in honor of biologist Dr. Michael Bigg. Known as the father of modern-day orca study; he was the first to identify that Pacific Northwest orcas specialized in hunting either fish or marine mammals, but not both.
In 2010, a published paper suggested that these marine mammal specialist orcas were genetically distinct from the salmon specialists, and had been for over 10,000 years. The authors proposed they might be considered a separate species, and the name “Bigg’s” was chosen.
Bigg was also the first to recognize that individual orcas could be identified (from simple black and white photos), just by the unique patterns and scars on the saddle patch, the gray area behind the dorsal fin.
He conducted the first census of West Coast orcas, sending out thousands of questionnaires in an attempt to identify the population size. Prior to this, the total number of orcas in the Pacific Northwest was unknown and was overestimated at “thousands”, when in fact questionnaires, and later the photo ID work showed a very different story.
The original population estimate was 350 animals, which turned out to be remarkably accurate. The work to document the Northern and Southern Resident populations, as well as transients, ultimately led to a ban against capturing orcas in these waters for captivity due to the severe impact on their populations.
The Southern Residents are still struggling today to recover from this lost generation of calves taken for captivity. But without the pioneering work of Michael Bigg, they would not be the most studied population on the planet, which ultimately should lead to better protections, and a chance for recovery.