Non-structural Deterrents and Opportunistic Dispersal in an Invasive Fish: The Role of Among-Individual Variation on Common Carp Movement

Dispersal decisions are often made at the level of the individual, but among-individual variation in dispersal behaviour is rarely considered in aquatic conservation and invasion control. To address this challenge, my thesis applied concepts of behavioural ecology to invasion biology. Using an invasive fish, Common Carp (Cyprinus carpio), as my study species, I examined the influence of among-individual behavioural variation on opportunistic dispersal and on the effectiveness of non-structural deterrents - methods used to limit the movement of non-native fishes. My thesis is comprised of a brief literature review and four research chapters that incorporate lab and field techniques to describe movement behaviours. My first research chapter (chapter 2) used choice-arena experiments to determine whether Common Carp express consistent individual differences in their avoidance behaviour of non-structural deterrents. I found CO2 levels required to force movement towards acoustic and stroboscopic stimuli varied across individuals. In chapter 3, these same deterrents were deployed at an outdoor fishway with more realistic field conditions. Native and non-native fish passage across the fishway was quantified to determine whether a behavioural deterrent (sound) can produce an avoidance response sufficient for conservation applications. This is the first study to find a phylogenetic signal in fish responses to a non-structural deterrent. In chapter 4, individuals captured at the fishway were measured for morphology,subjected to laboratory behavioural trials and then released to be acoustically tracked. Significant flooding provided individuals with a rare dispersal opportunity into a wetland. I found dispersal success was correlated with behaviour in the field, but not a behavioural syndrome expressed in lab tests. Finally, in chapter 5, I investigated whether Common Carp would consistently avoid a physiological deterrent (CO2) at the fishway. I observed a 10-fold decrease in Common Carp catch rates during stimulus activation and, unlike in chapter 3, there was no phylogenetic signal in avoidance responses. This research contributes to our understanding of how animals make dispersal decisions and the role of behavioural variation on biological invasions, and uses behavioural ecology techniques to advance applied aquatic conservation.

Department dc:contributor.department

Ecology and Evolutionary Biology

Year dc:date.issued

2021

Author dc:creator

• Bzonek, Paul Alexander

Advisor dc:contributor.advisor

• Mandrak, Nicholas E.

• Acoustic
• Barrier
• Behavioural Ecology
• Biological Invasion
• Common Carp
• Conservation

Statement dc:rights

• Attribution-NonCommercial 4.0 International

Licence dc:rights.uri

• http://creativecommons.org/licenses/by-nc/4.0/

Handle dc:identifier.uri

http://hdl.handle.net/1807/125887

OAI identifier oai:identifier

oai:utoronto.scholaris.ca:1807/125887