Date Thesis Awarded
4-2024
Access Type
Honors Thesis -- Open Access
Degree Name
Bachelors of Science (BS)
Department
Biology
Advisor
Randolph Chambers
Committee Members
Roger Mann
Matthias Leu
Abstract
Arctica islandica, ocean quahogs, have growth annuli that form similarly to terrestrial tree rings as records of yearly growth. Early growth increases linearly, however, the rate at which this growth occurs is impacted by extant environmental conditions. By recording growth trends of the first four years of life from a sample of juvenile A. islandica collected on Southeast Long Island and comparing these trends to previously unpublished data from Georges Bank and Long Island collections, I was able to identify different patterns of growth among the three sites. Southeast Long Island clams were subject to much warmer winters than either Georges Bank or Long Island and, while size at year one was larger, shell growth in subsequent years was quickly surpassed by the other sites, which both had a relatively similar growth rate. A. islandica growth has been shown to increase with increasing temperatures; the results of Southeast Long Island, however, suggest an upper boundary temperature at which growth can no longer occur. Additionally, higher growth rates in highly productive Georges Bank produced clams with the fastest overall growth rate, even with the smallest year one size. Both the temperature threshold and the impact of food availability in highly productive regions on growth need to be calculated in order to perform a day-degree analysis accurate enough to have growth serve as a proxy for temperature.
Recommended Citation
Cohn, Olivia, "Bivalve molluscs as recorders of ocean bottom water temperature: the role of juvenile ocean quahogs (Arctica islandica) in the mid-Atlantic" (2024). Undergraduate Honors Theses. William & Mary. Paper 2131.
https://scholarworks.wm.edu/honorstheses/2131
