Variable fish mercury concentrations in the Dehcho: effects of catchment control and invertebrate community composition

Samples/data collected by joint University-community monitor team: 1) Fish (15-20 individuals/species, up to 4 food fish species/lake): a. Captured with gill nets and dissected for muscle tissue (frozen for Hg and stable isotope analysis) and ageing structures; b. Fishing locations determined by local fishers and elders. 2) Benthic Invertebrates and sediments (min. 3 samples/taxa at 5 sites/lake): a. Profundal (deep) and littoral (nearshore) invertebrates collected with Ekman dredges and kick nets; b. Samples coarsely sorted in the field, divided in half, and: i) preserved in ethanol for taxonomic identification; ii) frozen for stable isotope and total and methyl Hg analysis; c. Sediments collected with an Ekman dredge, frozen for Hg analysis. 3) Zooplankton (min. 3 sample/size fraction at 3 sites/lake): a. Collected with vertical tows, size-fractioned; b. Half of each size fraction preserved in ethanol for community composition analysis, other half frozen for stable isotope and total and methyl Hg analysis. 4) Water (min. 5 sites/lake – top and bottom): a. Filtered and unfiltered water samples collected from each lake, and from influent streams and wetlands. Ultra-trace sampling methods used for Hg. 5) Abiotic: a. Catchment size and slope, lake area and volume, % wetlands and hydrology in catchment, underlying geology determined using GIS and field-based techniques.

Metadata Access
Creator Swanson, Heidi; Low, George
Publisher Canadian Cryospheric Information Network
Contributor Polar Data Catalogue
Publication Year 2018
Rights Research programs, CCIN, or ArcticNet take no liability for the use or transmission of this data
OpenAccess true
Contact hswanson(at); pdc(at)
Language English
Format Computer file
Discipline Ecology
Spatial Coverage (-120.591W, 61.255S, -119.135E, 62.167N)
Temporal Coverage Begin 2016-08-21T00:00:00Z
Temporal Coverage End 2018-12-31T00:00:00Z