Field counts of amphipods along benthic transects at Tule Red Tidal Restoration Site from November 2020 through December 2021

Amphipods (Gammarus sp.) were observed and collected from the Tule Red Tidal Restoration Site in Suisun Marsh (38.117843, -121.983199) in January-December 2021. All observations and collections were conducted in <20 cm of brackish water in secondary tidal channels on the restoration site within 0.25 miles of the provided GPS coordinates. All amphipods were collected under California Scientific Collecting Permit No. S-201970002-20281-001. Monthly field observations and captures were done at 5m intervals over eight semi-permanent 20 m transects established in paired Phragmites and native plant canopies in the same area of the marsh, where 0m indicated the edge of a tidal channel. We measured pelagic invertebrate biodiversity by capturing discrete water pools (~60 g water) using a turkey baster. The water samples were sieved using a 0.125 mm filter and rinsed with deionized water before preservation in a rose bengal-dyed 70% ethanol solution. The benthic samples were sieved and washed using a 0.5 mm filter and rinsed with deionized water before preservation in a rose bengal-dyed 70% ethanol solution. Preserved samples were sorted, counted, and photographed under a dissecting microscope. Counts per sample were normalized to the weight of the original sample.