Surface chlorophyll data were collected on October 30, 2024 while the R/V Monitor was underway collecting nutrient samples in the Providence and Seekonk River estuary. The average chlorophyll concentrations were categorized as good in all areas surveyed. Overall, chlorophyll ranged from 0.48 µg/L to 12.03 µg/L with an average of 2.11 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
Surface chlorophyll data were collected on October 23, 2024 while the R/V Monitor was underway collecting nutrient samples in the Providence River estuary. The average chlorophyll concentrations were categorized as good in all areas surveyed. Overall, chlorophyll ranged from 0.78 µg/L to 5.11 µg/L with an average of 2.96 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
Surface chlorophyll data were collected on October 17, 2024 while the R/V Monitor was underway collecting nutrient samples in the Providence and Seekonk River estuaries. The average chlorophyll concentrations were categorized as good in all areas surveyed. Overall, chlorophyll ranged from 1.23 µg/L to 11.31 µg/L with an average of 3.05 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
Phytoplankton samples were collected on June 12, 2024 at Bullock Reach and analyzed in the laboratory shortly after collection. Sonde data revealed the surface water temperature was 19.68°C, salinity was 24.22 psu, and chlorophyll a was 9.89 ug/L. The qualitative tow net sample had a short filtration time, and the filtrate was mostly clear. The analysis of the quantitative whole water sample revealed a total of 12,732,000 cells per Liter. The most predominant phytoplankton genus was Skeletonema spp. at 12,408,000 cells/L. Other representative genera include Chaetoceros spp. and Leptocylindrus spp. Prorocentrum spp. (see 200x phase contrast image below) is a dinoflagellate genus containing several toxic and harmful species. P. micans is one of the most common species in the genus. Prorocentrum is found in cold, temperate to tropical waters. This genus forms extensive red tides in many parts of the world, though blooms are usually harmless. It may excrete substances that inhibit diatom growth, but these substances do not enter the food chain or affect organisms at higher trophic levels.
Surface chlorophyll data were collected on September 25, 2024 while the R/V Monitor was underway collecting nutrient samples in the Providence and Seekonk River estuaries. The average chlorophyll concentrations were categorized as good in the Northern Providence River Channel and Edgewood, and as fair in all other areas. Overall, chlorophyll ranged 0.99 to 15.81 µg/L with an average of 5.14 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
Surface chlorophyll data were collected on September 11, 2024 while the R/V Monitor was underway collecting nutrient samples in the Providence and Seekonk River estuaries. The average chlorophyll concentrations were categorized as fair in all areas. Overall, chlorophyll ranged 2.45 to 33.57 µg/L with an average of 11.07 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
Surface chlorophyll data were collected on August 21, 2024 while the R/V Monitor was underway collecting nutrient samples in the Providence and Seekonk River estuaries. The average chlorophyll concentrations were categorized as good in the Seekonk River and Northern Providence River Channel, and as fair in all other areas. Overall, chlorophyll ranged 0.93 to 20.56 µg/L with an average of 4.42 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
Surface chlorophyll data were collected on August 14, 2024 while the R/V Monitor was underway collecting nutrient samples in the Providence and Seekonk River estuaries. The average chlorophyll concentrations were categorized as poor in the Seekonk River, and as fair in all other areas. Overall, chlorophyll ranged 1.31 to 109.86 µg/L with an average of 19.45 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
Surface chlorophyll data were collected on August 7, 2024 while the R/V Monitor was underway collecting nutrient samples in the Providence and Seekonk River estuaries. The average chlorophyll concentrations were categorized as fair in all areas surveyed. Overall, chlorophyll ranged 1.72 to 24.79 µg/L with an average of 7.32 µg/L. The chlorophyll concentrations from this date are presented in the map below using Inverse Distance Weighting (IDW) interpolation.
Water column profiles were conducted at seven locations in the Providence and Seekonk River estuaries on August 7, 2024 using a Seabird Electronics profiler. In the five days leading up to the survey, 0.95 inches of precipitation were recorded at T.F. Green. Water column stratification at the sites varied from weakly stratified at Pawtuxet Cove and Edgewood Yacht Club, to strongly stratified at Conimicut Point.
Dissolved oxygen (DO) conditions were below the hypoxia threshold (2.9 mg/L) in the lower portion of the water column at Edgewood Yacht Club, in the middle and lower portions of the water column at Pomham Rocks, and in all portions of the water column (upper, middle and lower) at India Point Park and Phillipsdale Landing. The highest fluorescence readings for the week were measured around 2 meters below the surface at Edgewood Yacht Club.