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Michael J. Paterson

Publications and source records attributed to Michael J. Paterson.

2 recordsLinked to original sources

The Zooplankton International Geospatial (ZIG) dataset: A global repository of spatiotemporal freshwater zooplankton community composition data from lakes and reservoirs to support ecological research

Zooplankton transfer substantial energy in aquatic food webs and are used as indicators of environmental change. Syntheses of zooplankton community dynamics globally require datasets that span a wide range of environmental gradients; however, these datasets are limited due to methodological differences across programs, taxonomic inconsistencies, and a lack of standardized metadata. To reconcile these challenges, we created the Zooplankton International Geospatial (ZIG) dataset, which includes original zooplankton, water physical and chemical variables, and lake morphometric data from 311 inland lakes and reservoirs. ZIG includes waterbodies ranging in size from 0.005 to 82,100 km 2 and spanning broad latitudinal (−47.26 to 64.90) and longitudinal ranges (−165.04 to 176.53). Temporal coverage for individual waterbodies ranges between 1 and 60 yr with sampling frequency ranging from annually to weekly. With its extensive coverage and content, we consider ZIG to be a cornerstone for future investigations of global scale lake biodiversity change.

Limnology & Oceanography - Letters

Lake depth and light conditions alter Mysis vertical distributions

Light regulates the vertical migration of many aquatic organisms. Mysis species couple pelagic and benthic habitats in lakes by diel vertical migrations (DVM), transporting energy and nutrients through the water column and food web. Although Mysis are generally assumed to remain on the bottom during the day, some have been observed in the pelagic zone during the day, indicating incomplete benthic-pelagic coupling in some systems. The degree to which light attenuation and lake depth interact to affect occurrence of mysids within the water column during the day is understudied. We used standardized Mysis net sampling in summers 2020 and 2021 across nine north-temperate lakes to test the hypotheses that 1) Mysis remain pelagic during the day at depths with sufficiently low light levels, and 2) pelagic-caught individuals during the day are, on average, smaller than those caught at night. To test these hypotheses, we assessed light, dissolved oxygen (DO), Mysis densities, and size distribution between night and day across bathymetric depths. In deep lakes and darkly colored shallow lakes, Mysis suspended in the water column during the day where light levels decreased to their light avoidance threshold (∼10 -5 to 10 -6 lx ). Mysis suspended in the water column during the day were smaller than those collected at night. Further, Mysis were not captured when DO reached levels < 3 mg/L, regardless of light conditions. Our results suggest that benthic-pelagic coupling by Mysis is mediated through light conditions, lake morphometry, and DO conditions, and may include some degree of size-dependent behavior.

Journal of Great Lakes Research