Presidential Address: The orca conjecture

Abstract

AbstractIn this address, I argue that the Southern Resident Killer Whale (SRKW) population has been negatively affected by commercial vessel traffic, tied to international trade, in the post‐1998 period. I present new data showing a dramatic increase in both the volume of kilometres travelled and the composition of vessel traffic in the Salish Sea. By exploiting recent work in biology linking vessel noise to changes in foraging and socializing behaviour, I argue that these changes have degraded their habitat significantly. Moreover, because SRKWs and Northern Resident Killer Whales (NRKWs) share prey, this negative vessel disturbance shock to the SRKW is magnified by the existence of across‐population competition. Vessel disturbance magnified by competition for prey has placed the SRKW on a slow‐motion path towards extinction.