Abstract
ABSTRACT The vertical migration patterns of eight freshwater mussel species were studied in outdoor enclosures. Individual experiments lasted from nine to 20 months, during which time mussels were observed three times per week. The mussels displayed two patterns of seasonal vertical migration; in both patterns populations of each species surfaced during spawning in spring and eventually reburied in autumn. These activities coincided with increasing spring water temperatures and decreasing autumn water temperatures, as well as increasing and decreasing durations of daylight. One group of species displayed a unimodal annual pattern, where most of the population surfaced in the spring and remained there until autumn. The second group displayed a bimodal pattern in which the population reburied itself after emerging in spring but then resurfaced and remained at the surface until autumn. We have not been able to associate this second emergence with any biological function. Patterns did not follow generic or subfamilial lines.
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.