We lucked out again on the water: clear skies, white tendrils of clouds, sun shining down on Clark Housty’s boat as we went about our work. Yesterday we deployed our kelp growth assays at 6 sites; 2 sites per channel (Spiller, Troup, Gunboat). Clark showed us how to fashion lines from the shore to an offshore float, and we attached our vexar cages with kelp to this line. This is the same method used for local Spawn-On-Kelp (SOK). Clark used huge boulders to weight the floats, and be as we tried, it was mainly Clark who had the muscle power to wrestle these on the boat then throw them overboard. At each site we did light measurements used a Licor PAR (Photosynthetically Active Radiation) sensor. This sensor measures the light that marine plants use to grow. We also took water samples from 1m depth which will eventually be analyzed for nutrient concentrations. The aim of this part of the project is to get measurements before the herring spawn, and then see if these change after the spawn occurs. This way we can assess the ecological importance of herring spawn. We also dropped some crab pots, and will fish these sites soon.
We made it to Troup Pass by the early afternoon and were hanging out in a little cove that we’d chosen as a site (Clark said this was a good spot as they spawned there last year). We were dropping the Licor sensor down and taking readings at 10 meter intervals when we heard a loud blow. Turning around quickly, an orca mom and calf were surfacing about 100m away! This orca had the tallest fin I’ve ever seen, it was narrow and towered over the other boat that was following them quietly (we hadn’t heard their approach). We abandoned our measurements and ducked out of the cove to see if we could catch another glimpse. Unfortunately they didn’t surface again, I guess they’d done a u-turn and we’re headed back down the pass. We went back to work, and about 45 minutes later, we were jolted away from our readings by another big noise; moving water and a blowing sound. About 10 meters away, a humpback had surfaced, probably combing the shoreline in search of herring. It surfaced a couple more times before it too took off down the pass. Overjoyed with our luck and the good omen that these sightings must spell (especially in terms of herring), we finished up the rest of our sites and returned to Bella Bella – a very productive day out on the spring water.
I slept in today, and just got a call from Clark – the herring have spawned in Troup, right where we saw the whales yesterday. They must have been letting us know that the fish were getting ripe! So now its time to get ready for the big spawning events that are bound to unfold shortly. While it’s very exciting that the spawn is upon us, in the name of experimental design we still need a couple of days to fish! We might have to change the design of this study as the spawning unfolds!