Zebra mussel densities, shell free dry mass and sample site information in Lake Winnipeg 2017-2019

At offshore sites, triplicate Ponar grabs (0.052 m-2) of sediment were collected from the M/V Namao. At nearshore sites, sediment samples were collected from a smaller workboat using a Petite Ponar grab (0.023 m-2) at the 3 m depth contour. Total sampling effort varied across the three years owing to time and logistical constraints (see Supplemental Table S1 for additional detail). Additional samples were collected at up to 18 shoreline sites (depths ranging from 0.2 - 1.0 m) around the lake in 2019. Depending on the type of substrate present, different sampling approaches were employed. For silt to gravel sized substrates, three to five 1 m long benthic kick-net (Canadian Aquatic Biomonitoring Network; CABIN, 400 µm mesh) drags were utilized. For cobble to rock sized substrate, three to five 0.25 m2 quadrats were placed randomly on the lake bed and up to five individual rocks were removed. All live mussels were removed from the rocks (when present) using a paint scraper. A sheet of tinfoil (Handi-foil®; PN 51805, standard foil wrap) was placed over the surface area of the rock and excess foil trimmed away. The foil was carefully cleaned of debris, folded and placed in a Ziploc®…

Publisher

Environment and Climate Change Canada

Resources

2

Catalogue metadata updated

2022-01-14