I led a research cruise to the Pacific Northwest in July, 2007 to study the unique range of redox environments found there. The west coast of Vancouver Island is an interesting place to study the influence of different O2 levels. There are a whole series of bays with different O2 concentrations in their bottom waters. Effingham Inlet is nearly always anoxic (no oxygen) year round and is a good place to examine a "classical" anoxic basin. Deer Bay in Clayoquot sound is anoxic most of the time, but trends towards oxic during the late summer when the bottom waters get exchanged. When we went there in April, the bottom waters had no O2 but still had nitrate, which is our definition of suboxic. By July, the bottom waters had no nitrate but instead had hydrogen sulfide, an indicator of anoxic waters. Nearby Tofino Bay is generally oxic year-round. We had heard that Nottka Sound was also anoxic, and went to take a look. We did not find anoxic or suboxic waters there but found a good deal of stratification, suggesting that this area goes seasonally suboxic at least.

More data to come