| Summary: | Thesis (M.Sc.)--Memorial University of Newfoundland, 2009. Biology Includes bibliographical references (leaves 3.26-3.38) The biological traits of the sea cucumber Cucumaria frondosa relevant from both ecological and resource management perspectives were investigated; including distribution, growth and predation on juveniles and adults, and population genetics. Natural densities were mainly dependent on substrate type and location. Spawning occurred from March to May in response to increasing phytoplankton abundance and larvae settled in ca. 5 weeks. Growth of juveniles and adults was slow (indicating ca. 25 years to reach market size) with seasonal patterns correlated with food supply. Juveniles of S. endeca fed upon post-metamorphic sea cucumbers, whereas adult feeding rates were modulated by temperature and biased towards small and injured sea cucumbers, suggesting that trawling may exacerbate predation pressure. Population genetic parameters are consistent with persistence in refugia through the last glacial maximum and local genetic patchiness is likely due to variations in recruitment. A precautionary management approach is advisable to ensure the sustainability of the fishery.
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