Phytoplankton samples were collected on October 18, 2023 at Bullock’s Reach and analyzed in the laboratory shortly after collection. It was a cloudy and chilly day on Narragansett Bay. The water was noticeably clear to almost 5 meters depth. Sonde data revealed the surface water temperature was 15.8°C, salinity was 24.9 psu, and chlorophyll a was 7.85 ug/L. The qualitative tow net sample had a medium filter time, and the filtrate was a light brown color. Some comb jellyfish were detected in the sample.
The analysis of the quantitative whole water sample revealed a total of 1,997,000 cells per Liter. The micro flagellates were found at 419,000 cells/L. The most predominant phytoplankton genus was Skeletonema spp. at 1,255,000 cells/L. Other representative genera include Chaetoceros spp., Leptocylindrus spp., and Cerataulina spp. This week’s featured image is the diatom Ditylum brightwellia, captured at 200x phase contrast.
