Graduation Year
2020
Document Type
Thesis
Degree
M.S.
Degree Name
Master of Science (M.S.)
Degree Granting Department
Marine Science
Major Professor
Heather L. Judkins, Ph.D.
Co-Major Professor
Brad A. Seibel, Ph.D.
Committee Member
Michael Vecchione, Ph.D.
Committee Member
Dale Griffin, Ph.D.
Keywords
DEEPEND, ontogengy, pelagic snails, vertical migration
Abstract
Large thecosome pteropods have a significant role in the pelagic ecosystem of the northern Gulf of Mexico (GoM). This research analyzed species abundances, vertical and horizontal distributions, and trends in shell thickness between 2011 and 2015. Pteropod samples were collected following the 2010 Deepwater Horizon oil spill by two midwater sampling programs: the Offshore Nekton Sampling and Analysis Program (ONSAP, 2011) and the Deep Pelagic Nekton Dynamics of the Gulf of Mexico (DEEPEND, 2015). All samples were collected using a 10-m2 Multiple Opening/Closing Net and Environmental Sensing System (MOC10) midwater trawl, with 3-mm mesh size. This gear sampled five discrete depths between 0–1500 m. To date over 13,000 pteropod specimens have been examined, and 25 species identified. Clio pyramidata was the most abundant species during both collection periods and five genera (Diacria, Clio, Styliola, Cuvierina, Cavolinia) demonstrated diel vertical migration from the meso- to epipelagic zone. Shell thickness comparisons between 2011 and 2015 were significantly different for several species, showing an increase in shell thickness in 2015. There was a slight positive correlation between shell length and thickness in several species.
Scholar Commons Citation
Shedler, Sarah M., "Large Thecosome Pteropods of the Northern Gulf of Mexico: Species Abundance, Spatial and Vertical Distribution With a Temporal Comparison of Shell Thickness" (2020). USF Tampa Graduate Theses and Dissertations.
https://digitalcommons.usf.edu/etd/8996
