Recently the water in Silver Bay has been exceptionally green, almost like it was seeing glacial run-off. I recall this happening last year as well, and at the time I noticed it I wondered if maybe it was dust from all the blasting and rock work being done on Sawmill Creek Road and for the Blue Lake dam project. When talking to some others about it, I was told about coccolithophores, a single-celled (mostly marine) algae that can turn waters blue-green color when they are abundant. Giving the seasonal timing of the color change along with the fact that rock work is greatly diminished this year (the road is done, and the dam is getting closer), it seems far more likely an explanation than rock dust from blasting. That said, it does raise some other questions for me.
In any event it’s a good time, especially with these sunny days, to get out and enjoy the newly completed road and separated bicycle/pedestrian path with normally amazing view now intensified by the colorful waters.
Questions:
- Does anyone else remember noticing this happen before last year (I don’t)?
- If it did not happen in prior years, what has changed? (Last year was exceptionally sunny during the summer, but this year has been quite rainy.)
- Why does the bloom seem mostly limited to Silver Bay and nearby locations where the blue-green likely originated in Silver Bay?
- Are there other places in the broader Sitka area where this is occurring?