Zooplankton

NEON’s long-term data collection will enable a more complete understanding of zooplankton species across the United States. The goals of NEON’s zooplankton sampling are to quantify biodiversity, number of species present (richness), and to enable DNA analysis of zooplankton communities.  These variables will be used to build a database over time that is compatible with existing research, that tracks changes in zooplankton community structure and function, and that traces the introduction of invasive species.

Zooplankton Data Collection

NEON collects zooplankton data seven aquatic lake sites.  These sites are located within four of NEON’s 20 domains, thus representing a variety of ecosystems across the United States. Currently, there are no aquatic sites in Hawaii (D20: Pacific Tropical).

Ideally, sampling will occur at these sampling locations for the lifetime of the Observatory (core sites) or the duration of the site’s affiliation with the NEON project (relocatable sites).

Morphological taxonomy samples are collected at the same time and location as samples used for DNA metabarcoding data products so the two can be correlated by data users. DNA metabarcoding data for zooplankton communities may be used for determination of diversity patterns in bulk samples.

Samples are collected using the most appropriate sampler for the depth of water. Locations deeper than 4 m are sampled using a vertical tow net, while locations shallower than 4 m are sampled using a Schindler-Patalas sampler. Typically, multiple (up to 3) tows or Schindler traps are collected and composited into a single sample. Zooplankton samples are collected on a volumetric basis.

Both types of samples, morphological taxonomy and DNA barcoding, are preserved in ethanol in the field and shipped to a contracting lab for processing or sequencing.

Spatial and Temporal Collection Design

Zooplankton samples for all related data products are collected during 3 month-long collection bouts per year in order to capture differences in community composition, abundance, and diversity. Macroinvertebrates, fish, zooplankton, microalgae, aquatic plants and macroalgae, sediment chemistry, and benthic microbes are all collected in the same time period. Zooplankton sampling occurs at 3 locations per site, resulting in up to 9 zooplankton taxonomy and 9 DNA samples per year.

Zooplankton samples are collected at three different locations at NEON lake sites. Samples are collected near the inlet, outlet, and buoy (deepest) sampling locations near the NEON sensor sets in lakes.

The referenced media source is missing and needs to be re-embedded.

A range of dates are determined based on historical data for each site including streamflow, ice on/off days, the accumulation of degree days, weather, and riparian phenology. All three zooplankton samples from one sampling bout must be collected within one day per site.

Sampling should occur at base-flow and ice-off conditions and will not occur directly following a flood in the stream of under ice in a lake. In the event of a flood, researchers will hold sampling for 5 days to allow the sediments to settle before recommencing.

Sample Bout 1: Spring

  • As an early-season date, this bout represents a period of rapid biomass accumulation after winter, typically after ice-off (where applicable) and prior to leaf out.
  • Bout 1 commences as temperature and light levels begin to increase, promoting an increase in primary productivity and/or a change in riparian phenology
  • In high elevation and/or high latitudes, bout 1 only begins after ice-off

Sample Bout 2: Summer

  • This bout targets low flows, high light (mid-summer), and maximum greenness of vegetation and riparian phenology

Sample Bout 3: Autumn

  • This bout represents the late growing season at each site during leaf-fall.
  • Bout 3 commences when light levels begin to decrease and temperatures cool, which results in water column shifts (e.g. decreased lake stratifications, biological community shifts, etc.)

Data Products

Zooplankton collection NEON.DP1.20219

Zooplankton DNA Barcode NEON.DP1.20221

Archival Zooplankton Samples

Archival samples are curated by the NEON Biorepository and available by request

  • Zooplankton samples (unprocessed)
  • Zooplankton specimens (processed)
  • Zooplankton: whole-sample DNA extractions

Why Zooplankton are Important Taxa to Track

Zooplankton data inform the NEON Grand Challenge area of biodiversity as well as provide specific information about the zooplankton community in lakes. The zooplankton assemblage responds to environmental stressors such as nutrient variability and such effects can be detected through changes in species composition, abundance, and body size distribution.

Zooplankton inhabit all layers of a water body and constitute a major link between primary production and higher trophic levels in aquatic ecosystems. Unlike algae or phytoplankton, zooplankton are microscopic animals that do not produce their own food. These small invertebrates float freely in the water column of lakes and oceans. Zooplankton are often filter feeders (sometimes predators) that feed primarily on algae while also being the main food source for planktivorous fish. They are important as both prey and consumers in the aquatic food web.

Using NEON to Solve Key Questions in Zooplankton Research

NEON data methods are carefully selected to provide standardized data sets across NEON field sites and that are compatible with existing historical data and/or data collected by other large-scale networks.

The layout of each field site and types of data collected are designed to provide a better picture of how an ecosystem is functioning by:

  • Collecting different types of organismal, meteorological, aquatic, soil, and biogeochemical data in close proximity to each other.
  • Collecting data at different spatial and temporal scales.

As part of NEON’s continental-scale open access platform, the aquatic sampling strategy is designed to measure aquatic biogeochemistry, biodiversity, and ecohydrology. Drawing on NEON’s open data, researchers can assess the health of aquatic ecosystems and analyze how these patterns relate to climate change, land use, and invasive species.

  • Here are a selection of research questions that could be addressed with NEON data:
  • How do zooplankton communities change with changing basal resources (phytoplankton) or predators (fish) across the observatory?
  • How do zooplankton communities respond to environmental disturbances, such as hurricanes and droughts?
  • How does the DNA sequencing data relate to taxonomy data? Can DNA sequencing be used as a tool for rapid bioassessment?