May 7th - Humpback & a Grey

Cascadia, one of our zodiacs, left the Nanaimo harbour, scanning the Salish Sea for blows and dorsal fins. Cascadia travelled all the way across the Strait of Georgia to the shores of the mainland before they finally saw the blows of a whale. It was a humpback, slowly diving and feeding in the muddy brown waters at the mouth of the Fraser River. The waters off the mainland can often be quite murky looking, as the freshwater flows from the rivers and mixes with the saltwater. These areas are often filled with life, small fish, plankton and other creatures thrive on the inflow of nutrient-dense waters. This humpback clearly found something to snack on, and after making a very long journey from the tropical areas of Mexico and Hawaii, this whale would be running on fumes.
Humpbacks spend their summers in our cold waters, enjoying the all-you-can-eat plankton and fish buffet, building up fat stores before starting the migration to the breeding grounds. During their migration humpbacks rely solely on the fat reserves they build up during the summer. This whale was busy feeding and doing shallow dives as we watched from the boat. While our naturalist tried their best to ID this whale, humpbacks can be tricky if they don’t fluke - the act of raising their tail out of the water before diving. A humpback's tail is the easiest way to ID them as individuals, using the marks and scars on the underside of the tail we match them to our catalogues. Some of our humpbacks have been photographed in our waters since the early 2000s, and these photos help us keep track of individuals.
This humpback was clearly too tired to be showing off its tail, though we did get dorsal fin photos. Some humpbacks have distinct dorsals with scaring that helps us ID them, and after looking over the photos we were able to match this humpback’s dorsal fin to a humpback known as Graze. She had a calf last year and spent the summer in the Salish Sea teaching her youngster all they need to know. With Graze back it will be interesting to see if her previous calf also returns to our region.

After leaving our humpback we continued travelling a little way before seeing another blow. This time it was a grey whale. Grey whales are not an uncommon sight in the Salish Sea but they are an uncommon sight on our tours. We had our first grey whale encounter outside Nanaimo last summer and they only stuck around for a brief time.
Typically the grey whales can be seen in the San Juan Islands and farther down the Washington coast, as well as along the mainland towards Vancouver. These whales travel from Baja California where they have their calves, and spend their summers travelling up the coastline like humpbacks, feeding and preparing for the next migration. These whales give birth in shallow shelters and lagoons in the warm tropical waters. It was this behavior that made them a primary target during the whaling era. Boats would round up mothers and calves in these shallow lagoons, kill the mothers and leave the calves. Throughout the whaling era, grey whales were hunted relentlessly, and their numbers were decimated. The pacific grey whale population is split into 2 groups, the western population which feeds off the shores of China to Russia is estimated at less than 100 individuals. The easter population, the whales that visit us, sits around 18,000-24,000 individuals.

Grey whales are cousins of the humpbacks and are also baleen whales. Unlike humpbacks they are bottom feeders, sucking the sand and muck into their mouths and pushing it back out through their baleen plates. If you go scuba diving in grey whale habitat you can often find sand ridges on the seafloor, showing where the whales have been eating. Due to the nature of their feeding, grey whales are very susceptible to parasites.

After watching our little grey whale feeding along the shore Cascadia departed and headed back towards Nanaimo, stopping to see harbour seals and Steller sea lions along the way.

All the photos below were taken by marine naturalist Val Watson.

Graze (BCY0523)

Graze (BCY0523)

Grey whale

Grey whale

Grey whale - they can be very hard to spot!

A banded eagle!