In collaboration with Cascade Sorte and Matt Bracken from UC Irvine, and Kristy Kroeker from UC Santa Cruz, we are currently up in Sitka Alaska carrying out seasonal sampling for our NSF-funded project “Collaborative Research: Effects of Multiple Aspects of Climate Change on Marine Biodiversity and Ecosystem Functioning”. Much of the current trip’s work centers around sampling water chemistry conditions in our focal tide pools and surveying what’s living in them (algae and invertebrates).
We have a team of people from all three institutions helping to carefully pull water samples to assess the carbonate chemistry in the pools, as well as nutrient levels, dissolved oxygen, salinity, temperature, and probably several other things I’m forgetting right now.
Some of this sampling happens during the short days, and a lot of it happens in the dark. Currently the sun rises around 8AM and sets at 4PM, and the timing of the low tides often drags us past sunset. All of these parameters that we’re measuring can be affected by what the photosynthetic algae are doing as the light levels rise and fall, and so we attempt to take samples both during the day when the algae are photosynthesizing, and at night when everything is respiring all of the oxygen in the tidepool (and affecting the acidity of the water).
Air temperatures are in the mid-30’s to mid-40’s F (2 to 7 C) depending on whether the sun decides to peek out, and we’ve had a bit of rain and snow. The ocean is about 42 F (6 C). There’s not doubt that this is mind-numbingly and toe-numbingly boring work (pump water, fill bottle, cap bottle, take bottle to shore, preserve bottle, repeat ad naseum), but the hope is that we’ll see some kind of pattern in the data once all of the samples are worked up in the months to come.
All of this work is being done ahead of our main manipulative experiment that starts in early April. In that experiment, we will be raising temperature and lowering pH in the pools during low tide to look at how the photosynthetic algae and the invertebrates that graze on the algae are impacted by warmer and more acidic water conditions.
You can find more pictures and updates from all of the project participants on Twitter with the hashtag #SitkaNSF.