The dimensions of each organism were measured with a Whipple grid and the biovolume was estimated using the simplest geometric shape (e.g., cylinder, cone, sphere, etc.) that best fit the shape of each taxon. Shapes were assigned according to Hillebrand et al. (1999). Biovolume was calculated for the first five organisms/counting units of each taxon identified in a sample. The average biovolume was then used to calculate total biovolume of each taxon in the sample.

Phytoplankton cell counts were collected from using a moored submersible flow cytometer from the Martha's Vineyard Coastal Observatory in the Northwest Atlantic Ocean from 20 May 2004 to 30 September 2004. Data were submitted by Dr. Robert J. Olson of Woods Hole Oceanographic Institution (WHOI). Cell counts were recorded as an ASCII (.txt) file.

This data release includes zooplankton data collected with a 64-micron mesh net from 9 transects in Lake Huron between April and August 2017. At each transect, data were collected at up to three sites, ranging in bottom depths from 18 to 82 m. The volume sampled at each site was estimated with a flowmeter. Micro- and macro- crustaceans were identified, enumerated, and measured using a dissecting or compound microscope. The data are in raw form.

Phytoplankton samples were collected from Lake Pepin (a natural, riverine lake on the Upper Mississippi River) from 2012-2014. The dataset includes phytoplankton community data (i.e., genus, species, biovolume, etc.), as well as zooplankton, rotifer, cladoceran and water quality data.

Phytoplankton samples were collected from Lake Pepin (a natural, riverine lake on the Upper Mississippi River) from 2012-2014. The dataset includes phytoplankton community data (i.e., genus, species, biovolume, etc.), as well as zooplankton, rotifer, cladoceran and water quality data.

Phytoplankton cell counts were collected from using a moored submersible flow cytometer from the Martha's Vineyard Coastal Observatory in the Northwest Atlantic Ocean from May-December 2006. Data were submitted by Dr. Robert J. Olson of Woods Hole Oceanographic Institution (WHOI). Cell counts were recorded as an ASCII (.txt) file.

This data release includes zooplankton data collected from a collaborative effort for Environmental Protection Agency’s Cooperative Science and Monitoring Initiative (CSMI). Zooplankton surveys were conducted during the growing season, from late April to early November, in two Lake Michigan transects in 2010, two Lake Huron transects in 2012, eight Lake Michigan transects in 2015, and nine Lake Huron transects in 2017. Zooplankton samples were collected by whole water-column tows at two or three stations in different bottom-depth categories (i.e., shallow, middle, and deep) in each of the transects. Due to the difference in bathymetry, some transects did not have a deep station. The shallow and middle stations have bottom depths of 11-27 m and 40-51 m, respectively, in both Lakes Michigan and Huron. As Lake Michigan is generally deeper than Lake Huron, the deep stations have bottom depths of 85-112 m in Lake Michigan and 64-90 m in Lake Huron. The dataset includes tables for sampling operation, zooplankton count, and zooplankton individual size, which may be used to derive zooplankton count or biomass per volume.

This U.S. Geological Survey (USGS) Data Release provides phytoplankton data collected from Milford Lake, Kansas, during July 27 and August 31, 2015. This data release was produced in compliance with the federal open-data requirements as a way to make scientific products associated with USGS research efforts and publications available to the public. The dataset includes all samples collected at three long-term U.S. Army Corps of Engineers (USACE) sites on Milford Lake. Phytoplankton were identified to the lowest possible taxonomic level and abundance (density) and biovolume are reported.

This U.S. Geological Survey (USGS) Data Release provides phytoplankton data collected from Milford Lake, Kansas, during July 27 and August 31, 2015. This data release was produced in compliance with the federal open-data requirements as a way to make scientific products associated with USGS research efforts and publications available to the public. The dataset includes all samples collected at three long-term U.S. Army Corps of Engineers (USACE) sites on Milford Lake. Phytoplankton were identified to the lowest possible taxonomic level and abundance (density) and biovolume are reported.

This U.S. Geological Survey (USGS) Data Release provides phytoplankton data collected from the Kansas River and tributaries, during July 2012 through February 2017. All data are reported as raw calculated values and are not rounded to USGS significant figures. This data release was produced in compliance with the open data requirements as a way to make scientific products associated with USGS research efforts and publications available to the public. The dataset includes all routine and quality assurance/quality control samples collected at two locations along the Kansas River (USGS station numbers 06887500, 06892350) and three tributary sites (USGS station numbers 06857100, 06887000, 06890900). Phytoplankton were identified to the lowest possible taxonomic level and abundance (density) and biovolume are reported.