Date Thesis Awarded

4-2018

Access Type

Honors Thesis -- Access Restricted On-Campus Only

Degree Name

Bachelors of Science (BS)

Department

Biology

Advisor

Dr. S. Laurie Sanderson

Committee Members

Dr. Jonathan Allen

Dr. Eric Hilton

Abstract

Despite being ecologically and economically important, little is known about the function of gill rakers in filter-feeding fish. This oral morphology is currently assumed to work as a deadend sieve. This assumption has a few limitations that are not consistent with observation and data from live and preserved fish. In a dead-end filtration model there is an inevitable problem with clogging as well as an inability to retain particles smaller than the mesh. However, there is minimal clogging in filter-feeding fish, and they have the ability to retain particles smaller than the ‘mesh’ created by their rakers. More recent research has proposed a mechanism of crossflow filtration in filter-feeding fish. Given the novel and elaborate raker morphology in the American shad, this thesis has used particle interactions and patterns of particle retention to study the fluid dynamics involved in filter-feeding mechanisms and to contribute to the assessment of whether these fish use a dead-end or crossflow filtration system. This use of particles suspended in water flow has provided evidence against the dead-end sieve model in the American shad, and instead supports a system much closer to a crossflow filtration model.

Recommended Citation

Bruzzio, Hannah, "Particle Interactions with the Gill Rakers in the Filter-Feeding American Shad (Alosa sapidissima)" (2018). Undergraduate Honors Theses. William & Mary. Paper 1256.
https://scholarworks.wm.edu/honorstheses/1256