Stream Temperature Monitoring Network

The Cook Inlet watershed is the most populated and fastest-growing region in Alaska; it is also home to the state’s renowned wild salmon runs, some of which are at great risk due to climate and land-use change. Cook Inletkeeper has documented warm water in local salmon streams since monitoring began in 2002, with summer temperatures routinely exceeding state water quality standards established to protect spawning and migrating fish.  Fisheries scientists warn that high stream temperatures make fish increasingly vulnerable to pollution, predation and disease.  Yet despite the association between warm water temperatures and reduced salmonid survivorship - there is little consistent, long-term temperature data for salmon streams in Alaska.  Without such basic information, it is impossible to gauge the health of Cook Inlet’s salmon habitats and resources, and equally difficult to develop management responses to improve watershed resiliency to climate change.

Inletkeeper Strategies

Cook Inletkeeper has developed the Stream Temperature Monitoring Network to build the science-based knowledge needed to identify thermal impacts in Alaska’s coastal salmon habitat. The Stream Temperature Monitoring Network for Cook Inlet is 1) collecting consistent, comparable temperature data for Cook Inlet’s salmon streams; 2) increasing our understanding of the rate of rising stream temperatures and areas of maximum exceedances throughout the basin; and 3) providing the knowledge and data needed to prioritize sites for future research, protection and restoration actions.

In 2007, Cook Inletkeeper began laying the groundwork for the Network by spearheading a novel effort to create a standardized water temperature monitoring protocol for Cook Inlet, which is easily transferable to other watersheds in Alaska. Water Temperature Data Logger Protocol for Cook Inlet Salmon Streams includes a detailed description of methods, equipment needed, and instructions on how to deploy data loggers in the field, how to program and download data, and how to perform maintenance and quality assurance measures. Having this information written for a general audience will make it easier for other Cook Inlet stakeholders and decision makers throughout Alaska to implement temperature monitoring to understand and respond to thermal change in local salmon-bearing watersheds.

In 2008, Cook Inletkeeper led a committee of state and federal agencies, NGOs, and community groups to create a monitoring design for Cook Inlet’s Stream Temperature Monitoring Network. This monitoring design incorporates sites and priority areas from 1) a 2001 USGS report that identifies sites within Cook Inlet with a predicted water temperature change of 3^oC or more based on air temperature models, 2) the Nature Conservancy’s Cook Inlet Basin Ecoregional Assessment, which identifies aquatic areas of biological significance, and 3) the Alaska Clean Water Actions (ACWA) database of priority waters. Additional consideration was given to Alaska Department of Fish and Game (ADFG) fish weir sites. The process of prioritizing and stratifying sites can be a template for temperature sampling designs in other watersheds in Alaska.

In May 2008, Cook Inletkeeper and its Partners began implementing the Stream Temperature Monitoring Network. We are now in the fourth year of collecting temperature data in 48 non-glacial salmon streams in the Cook Inlet watershed. See map above for site locations. For results from the first three years, read our latest report: Stream Temperature Monitoring Network for Cook Inlet Salmon Streams 2008-2010.

Current Work

In 2010, Cook Inletkeeper worked with Scenarios Network for Alaska Planning (SNAP) to get a better understanding of climate predictions on a regional scale. SNAP generated future scenarios of air temperature and precipitation conditions across the Cook Inlet watershed. By understanding these smaller-scale patterns, local communities will be better prepared for changing conditions in the years ahead. For more, visit: Future Climate Conditions in the Cook Inlet Watershed.

Also in 2010, Inletkeeper contracted with Watershed Sciences, Inc. to provide airborne thermal infrared imagery for 34 miles of the south fork of the Anchor River.  This exciting technology is an effective method for mapping spatial temperature patterns in streams. To learn more about thermal infrared imagery and how it can be used to identify important cold-water habitats important for salmon, visit Cold Water Refugia.

The quantifiable benefits of this work include:

• Providing resource managers with quantified thermal data on key Cook Inlet salmon systems to make better habitat and management decisions;
• Identifying salmon systems and habitat requiring enhanced protection or restoration efforts due to thermal stressors.

ADDITIONAL RESOURCES & LINKS

Kyle, R.E. and T.B. Brabets, 2001. Water temperature of streams in the Cook Inlet basin, Alaska, and implications of climate change. U.S. Geological Survey Water-Resources Investigation Report 01-4109. http://ak.water.usgs.gov/Publications/Abstracts/2001.Abstracts/CIBwatertemp.htm

The Nature Conservancy. 2003. Cook Inlet Basin Ecoregional Assessment. The Nature Conservancy of Alaska. Anchorage, Alaska. 118 p. http://www.nature.org/wherewework/northamerica/states/alaska/preserves/art12944.html

Alaska Department of Environmental Conservation. 2008. Alaska Clean Water Actions FY09 Priority Waters and Identified Actions. Online at: http://www.dec.state.ak.us/water/acwa/acwa_index.htm