Our two open boats pushed off the dock on this sunny morning. We headed across the Strait of Georgia in pursuit of whales, keeping our eyes peeled for tell-tale signs. The Strait of Georgia was nice and calm with beautiful glassy conditions, perfect for spotting any disturbances at the surface. Soon enough, we saw movement; not one, but two Humpback Whales! These two whales appeared to be resting; they meandered along without lifting their tail in the air, only staying underwater for short periods of time. The underside of a humpback’s tail is typically their most identifiable feature, they all have a unique shape and markings that allow us to tell individuals apart. This meant we had to identify this pair the more difficult way, by looking at their dorsal fins (which are pretty tiny on these huge animals). Thankfully, we were able to figure out we were with Scuba (BCY1225) and Crackle (BCY1227)!
The way Humpback Whales rest is termed unihemispherical slow-wave sleep (USWS). As with all marine mammals, humpbacks need oxygen for respiration. Being an aquatic mammal, they get this oxygen by coming up to the surface of the water they live in to breathe. This complicates matters when it comes to sleep. Unlike humans, humpbacks do not breath involuntarily; every breath they take is a conscious action. This means they can’t sleep the same way we do as shutting down their brain fully would lead to suffocation. Unihemispherical slow-wave sleep means they rest half of their brain at a time. While one half of their brain rests and one eye is closed, the other half of their brain remains active and the opposite eye is open, allowing them to breathe. This also means while resting, humpbacks are still able to travel along in the water and still scan for danger around them. After some time with this peaceful pair, we left to see what else we could find.

It didn’t take long before we stumbled upon another pair of humpbacks. These two were exhibiting stereotypical feeding behaviour wherein they’d surface for a few breaths before lifting their tails out of the water and doing a deeper dive in order to move down and then up the water column for food. Since we got a good look at their tails, it made them nice and easy to identify as Beak (BCX1606) and Prowler (BCX1660). Adult humpbacks need to eat around 3,000lb of food every single day so it’s no surprise that this is often what we see when we come across our whales. During our time with these whales, they decided they had spent enough time being social (we’ve all been there) and went their separate ways. We left them to their travels, with the aim of exploring the abundance of other wildlife our region has to offer.

The whales weren’t finished with one of our open boats though. Guests on Cascadia were treated to four more whales before they made it back across the Strait! The first of those was Incognito (BCX2053). They were spotted cartwheeling in the distance so our boat rushed over to see what all of the fuss was about. We suspect one of the reasons the whales can exhibit this type of behaviour is for communication. Causing big splashes on the surface is a good way to quickly let other whales in the area know they’re around as noise travels around four times faster in the water. We know Prowler had been headed in this direction so Incognito could have been saying “Hey, I’m over here if you’d like to hang out” or “I’m not in the mood for socializing right now”. Whatever the case today, Prowler continued on their way and our boat stayed with Incognito who carried on riding solo. While with them, Incognito did something else very exciting - he pooped! While this may not seem thrilling to some, it’s an extremely important part of the nutrient cycle. Tiny planktonic organisms will feed on the whale feces before going on to be fed upon themselves by the larger species in the food chain. We said goodbye to Incognito and started our journey back towards Nanaimo. Fader (BCY0195) made an appearance along the way, followed by Ghost (BCX1333) and Split Fin (BCZ0298) who were travelling together, but we only stayed long enough to identify each of them before pressing on.

Before making it home, we paused to check out some Pinnipeds in the form of Steller Sea Lions and Harbour Seals. Our final stop of the tour was along the Gabriola Bluffs, a popular nesting site for many species of bird, the most abundant of which is the Pelagic and Double-Crested Cormorants. With so much to see, we returned to dry land having had a fulfilling day on the Salish Sea.

Please enjoy the photos from the tour, taken by Marine Naturalists Val Watson and Lucy Willis!