Friday June 1, 2012
It takes a bit of teamwork and some good ol’ muscle to pull a large beach seine net through estuary waters. Last week Monterey Peninsula Water Management District (MPWMD) put out a call for volunteers to help with sampling activities in the Carmel River Lagoon for a steelhead population estimate and we were there to lend a hand. Using a rowboat and a couple of swimmers 300 ft. of seine net is deployed by in a half-circle. A seine is basically a fish safe net that comes in multiple mesh sizes and has weights along the bottom edge and floats along the top. Once deployed the ends of the net are pulled up on to the beach along with any fish trapped between the net and the shore. To estimate the population of steelhead (Oncorhynchus mykiss) the captured fish are marked with a photonic dye and released back into the lagoon where they were captured. When marked fish are recaptured in subsequent sampling a Petersen population estimate can be conducted to get an index of the steelhead inhabiting the lagoon. Using volunteers is a good way to conduct sampling that require a lot of hands for a short period of time and conservation groups like the Carmel Steelhead Association (CRSA) are essential to mobilizing willing participants.