CSI: Highline has detected the first adult coho salmon of the season swimming vigorously near the mouth of Miller/Walker creeks in Normandy Park.

CSI stands for the Community Salmon Investigation in Highline.

Creek steward Dennis Clark reported that with the creeks once again flowing clear and moderately, this fish has good conditions for migrating upstream and, hopefully, spawning.

The timing of its arrival last week is consistent with anecdotal information collected by the Normandy Park Community Club in past years (first adult observed in previous seasons: October 10, 2009, September 30, 2007, October 15, 2006, October 2, 2005).

On Oct. 7, 25 volunteers -half from Burien and half from Normandy Park - participated in a two-hour training to become CSI team members. The volunteers learned how to identify different salmon, how to safely walk the streams, and how to record data accurately.

The most exciting part of the training was being able to cut open two hatchery coho supplied by the U.S. Fish & Wildlife Service. According to Clark. This exercise showed how to evaluate whether fish have spawned, which will tell us the severity of "pre-spawn mortality" in the creeks.

The next day, the first two-person survey team surveyed the four regular survey locations on the two streams. The Saturday and Sunday survey teams were challenged by high flows in the streams from the 1.79 inches of rain that fell during the weekend but persevered and surveyed most of the locations.

Clark said the volunteers were reminded of the wildness that can be found in the Highline community when the first four survey teams also reported many juvenile salmonids in the streams, two sightings of great blue herons (probably preying on the juvenile salmonids), and one owl (probably a great horned owl.)

Teams will go out each day that stream/weather conditions allow through mid-December, when the chum salmon run typically ends (coho come in first, chum later). This regular observation of multiple locations by trained participants will provide robust data that can serve as a baseline against which to measure changes to stream health, according to Clark.

Locations for the inaugural CSI program are low in the basin to maximize the number of fish observed. If the program proves successful, additional locations upstream, including in Burien, will be added in 2011.
Data will be posted throughout the season at the CSI web page: http://www.kingcounty.gov/environment/watersheds/central-puget-sound/mi…

Volunteer response to the CSI program has been very strong and no more volunteer teams are planned at this point. Several more volunteers may be accepted into the program to serve as "back ups. Contact Clark at 206-296-1909 if interested.

The CSI: Highline program is part of the Miller and Walker Creeks Stewardship program, which is jointly funded by the cities of Burien, Normandy Park, and SeaTac; King County; and the Port of Seattle.