Abstract
Freshwater mussels are increasingly used to monitor metal pollution in freshwater systems. Mussels are long-lived, and age is a factor that may influence metal concentrations in their tissues. Species that can be precisely aged are most suitable for biomonitoring because they can be standardized for this factor. Precise age estimates are also needed for determining the effects of contamination on population parameters such as growth rate. Elliptio complanata, Anodonta implicata, and Alasmidonta undulata (family Unionidae) were collected from two Nova Scotia lakes contaminated with arsenic and mercury. Mussel shells were weighed, measured, and sectioned, and two independent counts of internal growth bands were made. External rings were also counted for A. implicata. Age estimates based on internal bands were most precise for E. complanata (r2 = 0.71 vs. 0.35 for A. implicata and 0.29 for A. undulata). Estimates based on external rings were more precise (r2 = 0.69) than those based on internal bands for A. implicata, but were believed to include disturbance rings. Shell length and weight were similarly correlated with age for a given species and population, but relationships were less clear in the lake with the more variable habitat. Elliptio complanata were much smaller at a given age in the more contaminated lake.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.