Sitka takes multi-faceted approach to ocean acidification monitoring



US Coast Guard Academy undergraduate Sydney Mills deploys the YSI sonde for the harbor buoy near the Sitka Sound Science Center. Photo by Lauren Bell.

The community of Sitka, led by the Sitka Tribe and the Sitka Sound Science Center (SSSC), is making a concerted effort to monitor ocean acidification in their backyard.

“As a local Tribal government, we’re most interested in how ocean acidification will manifest itself in the local ecosystem and how it will affect subsistence resources here,” said Esther Kennedy, the Sitka Tribe Environmental Specialist. “Initially, we will be collecting baseline near-shore data for Sitka Sound. We will be looking to see whether OA trends in the open ocean are muted or amplified here.” Among the questions the Tribe and the SSSC are hoping to answer is whether they can expect the local ecosystem to be more resilient to OA given the lower initial pH of nearshore waters.

New and upcoming monitoring efforts around Sitka include the following:

  • In late June, the US Coast Guard Academy deployed a YSI harbor buoy located just offshore from the Sitka Sound Science Center with subsurface instruments collecting temperature, salinity, chlorophyll, dissolved oxygen, and pH. The instruments are at 15m below the surface and provide near-real time data. The project is part of a collaboration with the SSSC under their Alaska Sea Grant Coastal Resiliency project.
  • UC Santa Cruz, led by Kristy Kroeker, deployed two sensors (SeaFet and SeapHOx) at a depth of 10 min two Macrocystis (kelp) beds this spring. Sitka Sound Science Center is assisting with monthly instrument retrievals, deployments, maintenance and data download. The center is also taking discrete water samples for pH, total alkalinity, nutrients, and salinity prior to each retrieval.
  • The Tribe was recently granted a permit from DNR to place an oceanographic buoy in state waters, and expect to deploy it in October with help from the US Coast Guard. The buoy will measure pCO2, pH, dissolved oxygen, salinity, and temperature using a Sea-Bird SeapHOx and a Pro-Oceanus pCO2 monitor.
  • The Tribe also received a BIA award for the upcoming year to install a Burke-O-Lator in their lab. This will make it possible to processes discrete water samples from partner communities, calibrate and monitor the performance of the instruments on the buoys, and to do continuous in situ monitoring in Sitka. It will be the third Burke-O-Lator in the state, joining the Alutiiq Pride shellfish hatchery in Seward and OceansAlaska shellfish Hatchery in Ketchikan.
  • In November, an ocean acidification kiosk,which has been on the dock in both Homer and Kodiak, will be transferred to Sitka. The interactive weatherproof kiosk, which was developed by the Alaska Marine Conservation Council, features video testimony from experts, fishermen and local leaders as well as easy to understand science for viewers of all ages. The installation at the Sitka Harbor will occur during the Sitka Sound Science Center’s annual WhaleFest event, Nov 3-6.

There is increasing interest from tribes across the state to get involved in ocean acidification monitoring and education. If you would like to be part of a new working group connecting tribes and OA, please contact OA Network coordinator Darcy Dugan,

For more information on the Sitka projects, contact Esther Kennedy, or Lauren Bell,

Comments are closed.