Gray Whale (Eschrichtius robustus) Feeding in Haro Strait

Tom Okey wrote:

We observed a gray whale (Eschrichtius robustus) feeding off of Island View Beach Regional Park for at least a couple of hours, adjacent to the south end of the park, perhaps between 100 and 200 m offshore, and travelling parallel to shore as if selecting a particular 'isobath' on the sandy slope of the seafloor at which to target feeding activities. Gray whales feed by straining invertebrates from the soft sediment that they suck up from the shallow seafloor. This individual was sounding, with its tail coming out of the water, but not very high as if it was not diving very. A portion of Canadian Hydrographic Service Chart 3313 is provided. It shows the sandy slopes just to the east of Island View Beach where this observed small gray whale was apparently feeding.

It appeared to be a relatively small individual, and this size description was also observed by a paddle boarder who got quite close. It was a very light colored whale with a very light colored tail as well. It had no dorsal fin. This may be a juvenile gray whale that was born this year in Scammon's Lagoon, San Ignacio Lagoon, or Magdalena Bay, Mexico.

An adult male gray whale was discovered dead in early April floating in Sidney Channel, about 5 km northeast of where this younger whale was feeding, raising the possibility that this younger individual may have been travelling with the adult toward the Bearing Sea when they took refuge in the Salish Sea (e.g. the Haro Strait of the Strait of Georgia). It's possible that this youngster cannot continue the journey to the Bering Sea without an older guide, and thus has taken refuge/residence in the area where the older individual died and where some food is available.

An unusually large number of gray whales have washed up dead during the first months of 2019. It is possible that this older individual could not complete the long journey to the Bering Sea, due to lack of food, as discussed in the news coverage on this regional event. Another potential cause of death of that individual could have been ingestion of plastic pollution. A necropsy by Fisheries and Oceans Canada concluded that a ship strike was not the cause of death.

This may be the first documented observation of a gray whale off of Island View Beach since industrial whaling in the region extirpated them from all parts of the Strait of Georgia, including the Haro Strait. There is a report of a gray whale off of Cordova Bay, a few kilometers south of this sighting in the Haro Strait about 4 years ago. It is a relatively new occurrence to have gray whales in the Strait of Georgia since industrial whaling ended.

Since gray whales have recovered their population during the last couple decades---now >20,000 in the Eastern Pacific---it is not so uncommon for young-of-the-year gray whales to take residence at locations along the coast between Mexico and Alaska rather than making the full trip to the Bering Sea for summertime feeding. Some gray whales, for example, have become resident in the Clayquot Sound on the west coast of Vancouver Island, but gray whales becoming a resident on the east side of Vancouver Island in the Strait of Georgia, including the Haro Strait, is novel and unusual since the end of industrial whaling.

John Calambokidis, Research Biologist, Cascadia Research, provided the following consult:

This has been an unusually high year for gray whale mortality and we have had over 20 dead gray whales washing up so far this year in Washington waters alone. It is likely to rival or exceed the record number of deaths documented in 1999-2000 which was the previous record mortality years. Most dead animals were emaciated and this event is likely the result of both a now fully recovered eastern North Pacific gray whale population intersecting with a poor prey year last year in their primary Arctic feeding areas. Along with this mortality has been increasing numbers of gray whale showing up this spring in unusual areas and many of these appear to malnourished animals likely in a desperate search for feeding areas after the 3-4 month annual fast.