Investigating the early life history of bay scallop, Argopecten irradians, using mesocosm experiments
Description
TitleInvestigating the early life history of bay scallop, Argopecten irradians, using mesocosm experiments
Date Created2021
Other Date2021-10 (degree)
Extent1 online resource (ix, 115 pages)
DescriptionBay scallops, Argopecten irradians, were once an abundant estuarine species, associated with seagrass beds ranging from the Gulf coast and along the Eastern coast of the United States. However, due to the presence of harmful algal blooms (HABs), loss of seagrass habitat, and increased predation, bay scallop populations have significantly declined across their entire range. Restoration efforts are underway in many coastal water bodies with varying success. Important data gaps regarding habitat requirements for bay scallops at all life history stages still remain. It was the overall goal of this dissertation project to identify and further examine those data gaps. Bay scallop life history can be divided into three segments: (1) pelagic larva, (2) juvenile, and (3) adult. Each stage has its own unique habitat requirements and specific selection pressures. This body of work was comprised of four main objectives, (1) determine if ctenophores prey upon bay scallop larvae, (2) quantify bay scallop larvae swimming behavior under different environmental conditions, (3) determine if juvenile bay scallops selectively prefer seagrass blades coated with epiphytes, and (4) examine the effects of seagrass shoot density on adult bay scallop survival, growth, and physiological health. The main research findings were, (1) ctenophores are important predators of bay scallop larvae, (2) bay scallop larvae mostly hover when exposed to salinities in the range of 20 to 30 ppt, but when exposed to warm conditions (30ºC), they swim upwards at a faster rate than those in 23ºC conditions, (3) juvenile scallops do not demonstrate a preference for seagrass blades coated in epiphytes and were instead observed to attach to any available vertical substrate, and (4) increasing seagrass shoot density adversely impacted the concentration of bioavailable phytoplankton but did not have a negative effect on bay scallop health. Taken together, these results suggest that predation is an important driving factor inhibiting bay scallop population recovery. Restoration efforts need to account for predation at the larval stage. Suitable habitat for larval settlement needs to be identified and maintained as juveniles and adults will continue to require it as a spatial refuge from predation.
NotePh.D.
NoteIncludes bibliographical references
Genretheses
LanguageEnglish
CollectionSchool of Graduate Studies Electronic Theses and Dissertations
Organization NameRutgers, The State University of New Jersey
RightsThe author owns the copyright to this work.
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