This week for Wildlife A to Z we address “Quantities” in terms of Bigg’s orcas- pod sizes, population and amount of vocalizations! All orca ecotypes are unique (e.g. Southern Resident orcas, Bigg’s orcas, Offshore orcas), behaving, vocalizing and eating in similar but also very different ways. Bigg’s, or transient orcas, travel in small groups compared to another West coast ecotype, Southern Resident orcas.
Bigg’s pod sizes typically range between 2-5 individuals. Why do groups only get so big? Keep reading! Bigg’s orcas make little to no vocalizations while hunting due to their prey type, marine mammals. Seals, sea lions and baleen whales that are hunted by the Bigg’s orcas are all able to hear the orcas’ communication – meaning they have to be very stealthy hunters so that their prey cannot hear them approaching. If you are in a larger group, this increases the chance you might be seen or heard. New orca mothers may leave maternal families with their own offspring in order to control group size. The Bigg’s orca population is growing, due to a high number of prey in the Salish Sea- that is, healthy populations of seals and sea lions.
There are roughly 200 Bigg’s orcas that move quite regularly throughout the Salish Sea, part of the total estimated 350 that typically use coastal areas. There are an estimated 500 individuals in the Bigg’s orca population, with 120 calves born just in the last ten years. Here are some photos of Bigg’s orcas being very active- the first photo displays some hunting behaviour! Information: Pacific Whale Watch Association, Encyclopedia of Puget Sound, The Marine Detective. …#explorebc @hellobc @destinationgreatervictoria