MS Thesis Defense - Environmental Science and Policy

MS Thesis
Department of Environmental Science and Policy
College of Science
George Mason University

Candidate: Jose R. Meneses Montano
Defense Date and Time: April 15, 2026 at 1:00pm
Defense Location: Potomac Science Center, Room 3102
Title: Spatiotemporal patterns and morphological impacts of parasitic coinfection in an estuarine crab host

Thesis Director: Dr. Amy Fowler
Committee: Dr. Daniel Hanley, Dr. Sarah Goodnight, Dr. April Blakeslee

ABSTRACT

This study examined coinfections by the invasive barnacle Loxothylacus panopaei and putatively native entoniscid isopod Cryptocancrion brevibrachium in Chesapeake Bay mud crabs. Results showed that coinfections were exclusively in Rhithropanopeus harrisii, particularly in larger males. Notably, the presence of one parasite increased the likelihood of infection by the other, suggesting reciprocal facilitation. While the invasive barnacle was the primary driver of host feminization—widening the male abdomen to resemble a female’s—coinfection slightly amplified this effect. These findings highlight how invasive species can influence native disease dynamics and intensify the morphological manipulation of host populations.