Item Details

title

AMPHIBIOUS FISHES: TERRESTRIAL LOCOMOTION, PERFORMANCE, ORIENTATION, AND BEHAVIORS FROM AN APPLIED PERSPECTIVE

author

Bressman, Noah R

abstract

A wide diversity of fishes exhibit amphibious behaviors for a variety of reasons. However, it is unknown how most amphibious fishes orient in terrestrial environments. Furthermore, while there has been some research into why fish emerge onto land, motivations for emersion can differ between species and data is deficient for many. Additionally, the terrestrial behaviors of many amphibious fishes have not yet been described. The goals of this dissertation are to determine the senses and cues mangrove rivulus (Kryptolebias marmoratus) and walking catfish (Clarias batrachus) use to orient in terrestrial environments, describe the conditions that encourage emersion in northern snakehead (Channa argus) and walking catfish, and describe the terrestrial locomotor behaviors of northern snakeheads and Neotropical suckermouth catfishes (Loricariidae). Behavioral assays with a variety of visual and chemical stimuli were used to determine the cues these fish use to orient while emerged. Experiments with a variety of environmental conditions and crowd-sourcing surveys on walking catfish observations were used to determine conditions that promote terrestrial emersion. High-speed videos were used to describe terrestrial behaviors. Vision is widely used in amphibious fishes and mangrove rivulus use reflections, colors, and contrast to orient on land, in addition to the otolith-vestibular system. Walking catfish also use chemoreception to orient with respect to chemical signals they are in direct contact with and over a distance. This is the first confirmed case of fish using chemoreception for orientation out of the water, which appears to involve aerial taste using their barbels. Snakeheads emerge under poor aquatic conditions, including low pH, high salinity, and high [dCO2]. Walking catfish emerge under a variety of conditions, but primarily emerge during the rain, particularly out of flooding storm drains. Snakeheads use a form of axial-appendage-based terrestrial locomotion, but perform better on complex substrates. Armored catfishes use an entirely new form of axial-appendage-based terrestrial locomotion – flooping- characterized by high asymmetry. Flooping is very similar across multiple armored catfish species. As many of these are invasive species, incorporating knowledge of their amphibious behaviors, performance, and orientation can help us better understand how they could disperse overland, improving management plans and risk assessments.

subject

Behavior

Emersion

Fish

Functional Morphology

Locomotion

Orientation

contributor

Ashley-Ross, Miriam A (committee chair)

Marrs, Glen (committee member)

Conner, William (committee member)

Anderson, T. Michael (committee member)

Gibb, Alice C (committee member)

date

2020-05-29T08:36:08Z (accessioned)

2020-05-29T08:36:08Z (available)

2020 (issued)

degree

Biology (discipline)

identifier

http://hdl.handle.net/10339/96844 (uri)

language

en (iso)

publisher

Wake Forest University

type

Dissertation