There are two species of killer whale found in the Salish Sea — they are Bigg's killer whales, the marine mammal-eaters, and southern resident killer whales, that eat salmon. The two subspecies could not be having more different years.
Both are setting records this year, but in opposite ways.
Keeping up with a decade-long trend, Bigg's killer whales are being seen more than ever. Southern resident killer whales, however, are having one of their worst years ever recorded.
The changes in whale population sightings have direct correlations with human policies and practices, based on decades of expert observation.
Puget Sound orcas set sighting records
The Pacific Whale Watch Association reports that data obtained by the Orca Behavior Institute (OBI) shows more Bigg's killer whale sightings in 2023 than any other year.
OBI tracks whale sightings reported by professional whale watchers, regional scientists and regional sightings groups. The reports are then confirmed with pictures. Based on these reports, the groups say there have been 1,270 unique Bigg's killer whale sightings between January 1 and October 31, 2023.
The record for most Bigg's sightings in a year was set in 2022, at 1,220. This means 2023 beat the record by 50 sightings with two months still left in the year.
This number reflects sightings of distinct groups of Bigg's killer whales on a specific day. Multiple sightings of the same group will not be counted more than once, according to the press release.
"Ten years ago, we were only getting 15% of that," OBI director Monika Wieland Shields stated in a press release. "This is the ninth year out of the last ten that the record has been broken."
Shields notes there was a slight decrease in observations in 2020, but that is likely due to COVID-19 impacting whale watching and observation opportunities. It is not necessarily a reflection of the population.
Conversely, the southern resident sightings have decreased dramatically in recent years. Based on current numbers, 2023 has recorded the second-lowest amount of sightings ever. OBI data shows only 2021 had fewer sightings.
Human impact on Salish Sea orcas
So, why are the numbers changing so drastically? Orca populations in the Salish Sea are directly impacted by multiple forms of human interference, often unintentional.
Historically, Bigg's killer whales were not often seen in the Puget Sound. It wasn't until protections were in place for seals and similar mammals — what Bigg's killer whales eat — that the sightings began to increase. Over time, this trend has only continued.
Washington, Oregon and Alaska used to have bounty programs targeting harbor seals, as they were considered a threat to local fisheries. It wasn't until these programs were eradicated in 1960 that these mammals began to populate the area again.
The populations thrived after the 1972 Marine Mammal Protection Act — luring in the Bigg's killer whale groups.
"What's happening with Bigg's killer whales right now is truly remarkable to witness," stated PWWA executive director Erin Gless in the press release. "People once referred to them as 'transient' killer whales because sightings were so rare, but now we're seeing them almost daily, and we have their food to thank for that."
The story goes quite differently for southern resident orcas. Their food of choice, salmon, have become less and less fruitful over time, driving them elsewhere.
Chinook salmon have been decreasing in size and abundance for several decades now, according to the U.S. Environmental Protection Agency. There are numerous factors impacting the salmon's presence. Some of these include:
"Until we restore the major Salish Sea Chinook salmon runs, particularly on the Fraser River in British Columbia, it's clear the southern residents will continue to spend more time on the outer coast where they have the chance to encounter a wider variety of salmon runs from different river systems," Shields stated in the press release.
