Barkley Sound is riddled with phenomenal dive sites, with some of the best diving on Vancouver Island in terms of marine life and variety of dive types. Walls, reefs (not the coral kind), islets and more are scattered through the area, and the Hosie Islets are no slouch in the fantastic dive department!
The largest of them, Hosie Island, has a fantastic wall, ready for intrepid divers to descend along. Starting from the very noticeable crack on the southern part of the island, going left or right and down are your options. There is something of a shelf around 10m, and then after that the bottom disappears into a dark green abyss. I’ve been there twice, and maxed out my depth at 20m, but you could very easily turn this into a technical dive if you so desired. It goes that deep. Needless to say, the water is quite cool, rapidly dropping to 9˚C from a 16˚C surface temperature. The top 3m to 5m can be quite mucky, but vis clears up quite nicely at depth. Currents are light to nil at depth, making for a pleasant dive. Lights are HIGHLY recommended for this dive, since Pacific Northwest waters love to get dark fast, and it can be hard to spot some of the life around you without one!
Back in 2010 when I completed my CAUS Scientific Diver course with BMSC, we went to the main island for our REEF Lv.2 Surveyor test. This should be a strong indicator to you of how much and how varied the life on this wall is! Schools of mixed rockfish, various sculpins, wolf eels, and more are common sights here. Invertebrates are well represented as well, with numerous sea stars (including the “slime” or “cushion” star!), ascidians, squirts, and anemones being present. Have your camera out and ready when you’re diving here, and be ready to switch to macro at the drop of a hat!
Overall, this is one of the nicest dive sites in Barkley Sound, and definitely worth checking out if you’re in the area. Be ready for the dark though, and be gentle, some of the invertebrate life can be quite delicate, so good buoyancy is key here. An easy dive, it easily falls into intermediate for skill level, owing to the combination of factors like depth, being a wall dive, the darkness and the cold. If you’re up for it though, check it out!