The Vertical and Horizontal Distribution of Bryozoan Larvae in the Western Atlantic and the Gulf of Mexico

• Main Author: Mackey, Ellie
• Other Authors: Young, Craig
• Format: Thesis
• Language: English
• Published: University of Oregon 2024
• Subjects: larva; cyphonautes; oceanography; currents; bryozoan; North Atlantic
• Online Access: https://scholarsbank.uoregon.edu/xmlui/handle/1794/29971

Years of oceanographic cruises and larval collection around the Gulf of Mexico and the Western Atlantic margin revealed the prevalence of two main morphotypes of bryozoan Cyphonautes larvae. This thesis explores the hypothesis that these are two separate and distinct species, a hypothesis that is supported by observations of horizontal distribution, depth distribution, and morphology. Further I explore the potential life histories and areas of origin of the two morphotypes. Using distribution mapping as well as ocean particle tracking programs to create reverse trajectory models I show that morphotype 1 is likely the larva of a pseudoplanktonic bryozoan, Jellyella sp., that disperses on floating algae with the circulation of the north Atlantic gyre. Morphotype 2 occurs mostly in the Gulf of Mexico, with individuals outside the Gulf associated with the Gulf Stream and the Florida Current.