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This zooplankton dataset is derived from two ecosystem experiments conducted at the Iowa State University Horticultural Research Station (42.110005, -93.580454) in six experimental ponds.

Several lakes in Iowa were undergoing targeted harvest of bigmouth buffalo and common carp (Cyprinus carpio) and this experiment asked, does the density of bigmouth buffalo within a shallow lake affect its ecosystem resilience to pulse perturbation? In summer 2019, the ponds were split into three experimental pairs containing no fish, a harvested density (150 kg/ha) of bigmouth buffalo (Ictiobus cyprinellus), and an ambient density (450 kg/ha) with densities based on surveys conducted in Iowa shallow lakes. One pond from each experimental pair was subjected to a pulse nutrient loading event of phosphorus and nitrogen at a 25:1 ratio in order to simulate heavy runoff from a storm event 4 weeks following addition of bigmouth buffalo.

Whether energy is cycled through benthic or pelagic pathways in foodwebs may have an effect on ecosystem resilience to pulse nutrient loading events. The more 'coupled' a food web is between benthic and pelagic pathways, the more efficiently it could cycle an influx of nutrients. In summer 2020, the ponds were again split into three experimental pairs to ask, does the degree of benthic-pelagic coupling within a food web affect ecosystem resilience to pulse nutrient loading. The ponds contained either bluegill-perch (low benthic-pelagic coupling), bluegill-perch-largemouth bass (intermediate benthic-pelagic coupling), or bluegill-perch-largemouth bass-fathead minnows (high benthic-pelagic coupling). One pond in each experimental pair was subjected to a nutrient pulse of nitrogen and phosphorus at a 25:1 ratio twice: once four weeks after fish addition and again another four weeks after the first nutrient pulse.

Zooplankton were sampled by vertically towing a Wisconsin net with 63 μm mesh from a depth of 1 m. The zooplankton sample was concentrated to approximately 60 mL using a 63 μm mesh cup and then 60 mL of 10% formalin sucrose solution was added to preserve the organisms. After 5 days in the formalin solution, the sample was transferred to 70% ethanol for storage prior to identification. For each sample, all of the zooplankton were identified and enumerated in a 1 mL subsample. Using a stereomicroscope, zooplankton were identified to genus for cladocerans and rotifers, and family for copepod. If 60 organisms were not identified in the first 1 mL subsample, an additional 1 mL subsample was enumerated. Up to 25 individuals from each taxa were also measured for length to calculate biomass using allometric relationship. For statistical analysis the zooplankton taxa were divided into calanoids, cyclopoids, copepod nauplii, rotifers, small-bodied cladocerans (i.e., Bosmina, Chydorus), and large-bodied cladocerans (i.e., Daphnia, Camptocercus, Ceriodaphnia, Simocephalus, Diaphanosoma).