T099 Bella, T099D, and T124A1 Bonapartes (inner coast subpopulation)
Photo Credit: Gary Sutton
The West Coast Transients (Biggs) Outer Coast Subpopulation consists of at least 211 individuals, though an exact count is not currently available due to their pelagic nature compared to the Inner Coast Subpopulation. They are silent hunters, often staying underwater for long periods of time with little to no vocalizations. They're also not as surface active as the resident ecotypes, with very little breaching, splashing, or other disruptive behaviors during their hunts. They often celebrate a successful hunt with breaches, tail slaps, spyhops, and other surface-active behavior.
Range map. Red is the Outer Coast Subpopulation range, yellow is the Inner Coast Subpopulation range, and red-yellow stripes are where the subpopulations overlap.
Figure from McInnes et al., 2025 (https://doi.org/10.1371/journal.pone.0325156)
Species: Orcinus orca rectipinnus
Population Numbers:
Transients, like other populations, are matrilineal, but matrilines often break away into groups of 4-6 to keep up stealth. Due to the prey they hunt, they rarely vocalize to avoid detection by their prey. There are ~211+ transients in this subpopulation.
Population Status: Threatened (CAN- whole population)
Study Years: 1976-present (whole population)
Range: California Coast to Haida Gwaii
Diet: Marine Mammals- 49% California Sea lions, 7% northern elephant seals, 20% gray whale calves (spring only), 8% Pacific white-sided dolphin and common dolphins