Zooplankton

Zooplankton sampling began in April 2014. Samples are collected by towing nets through the water column. Two types of nets are used: a single ring net (200 micrometer mesh) towed up and down (vertical) throughout the full water column and double-ring (bongo) nets (335 micrometer mesh) towed at an angle through the upper 30 meters of the water column. Flow meters are attached to the nets to measure the amount of water sampled. Vertical tows are done at three locations and bongo tows at two of those locations two times a month February-November and once a month January and December Other water quality parameters and phytoplankton are collected with the zooplankton samples.

Samples are analyzed at the University of Washington to determine abundance and biomass (weight) of different types of zooplankton. Zooplankton captured in vertical tows are identified to the species level whenever possible for most taxonomic (classification) groups. Broader taxonomic groups are identified in the bongo tows, with some groups identified to the species level. Life stages (e.g., whether they are larvae or adults) for certain organisms are also determined.