Author Type

Graduate Student

Date of Award

2013

Document Type

Thesis

Publication Status

Version of Record

Submission Date

October 2026

Abstract

Elasmobranch fishes use electroreception to detect electric fields in the environment, particularly minute bioelectric fields produced by potential prey. A single elasmobranch family (Potamotrygonidae) is composed of obligate freshwater stingrays endemic to the Amazon River. A freshwater existence has imposed morphological adaptions on their electrosensory system due to life in a high impedance medium. Because their electrosensory morphology differs from their marine relatives, freshwater stingrays may demonstrate corresponding differences in behavioral sensitivity. The objective of this study was to quantify behavioral sensitivity of the obligate freshwater stingray Potamotrygon motoro to prey-simulating voltage. The voltage produced by common teleost prey of P. motoro were measured and replicated for behavioral trials. The best response was 10.62 cm, and the smallest voltage gradient detected was 0.005 mVcm-1. This sensitivity is reduced compared to marine species. The conductivity of the medium, more so than ampullary morphology, may dictate sensitivity of the elasmobranch electrosensory system.

Extent

viii, 44 p. : ill. (some col.)

Comments

by Lindsay L. Harris.|Thesis (M.S.)--Florida Atlantic University, 2013.|Includes bibliography.|Mode of access: World Wide Web.|System requirements: Adobe Reader.|by Lindsay L. Harris.

Identifier

FADT3362382

Format

pdf

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