The Effect of Uncertain Predation Risk on the Expression of Neophobia in Convict Cichlids Archocentrus Nigrofasciatus
Date
2024-03-05
Authors
Journal Title
Journal ISSN
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ORCID
Type
Thesis
Degree Level
Masters
Abstract
Predation exerts a pervasive and unforgiving selection pressure such that it can influence prey life history, morphology, physiology, and behaviour. The combined effects of climate change, anthropogenic disturbances, and invasive species can lead to short- and long-term changes in how prey mitigate predation risk. As a result, many animals are likely experiencing increasing amounts of novelty and uncertainty about their environment. In a predation context, uncertainty can be linked to the relevance of the antipredator response to the information contained within a predator-related cue. Increased uncertainty may have consequential impacts on the decision-making and risk-assessment abilities of various prey species. Thus, understanding how prey manage uncertainty and the ecological factors driving uncertainty is fast becoming a pressing issue for ecologists and conservation biologists. Neophobia, or the fear of novel stimuli, has been proposed as a way for prey to respond to increased uncertainty without the costs of learning unknown predator-specific information. While neophobia was initially presumed to emerge from high levels of predation risk, recent evidence has shown that uncertainty, instead of the level of risk, is likely the key driver of neophobia. However, the specific ecological factors that drive uncertainty and, by extension, neophobic responses remain unclear. Using juvenile convict cichlids (Archocentrus nigrofasciatus), I explored the extent to which neophobia emerges in response to the different factors that contribute to the uncertainty associated with predation risk. These factors were namely the unreliability of risk assessment cues and the temporal unpredictability of risk. Upon investigating the effect of cue reliability on neophobia, I demonstrated that neophobia is maintained after repeated encounters with unknown (i.e., unreliable) alarm cues from an unrelated species following exposures to known and highly reliable conspecific alarm cues. While I failed to find an effect of temporal predictability of risk on neophobia, I found that a lack of temporal pattern in predation risk induces neophobia in prey regardless of the level of risk intensity. My thesis identifies how certain factors that relate to how predation risk is perceived shape the uncertainty that prey experience and the resulting neophobic response. Faced with a rapidly changing world, understanding how prey manage novel cues provides valuable knowledge that can inform conservation and management efforts of ecologically and socioeconomically important key species.
Description
Keywords
Uncertainty, Convict cichlids
Citation
Degree
Master of Science (M.Sc.)
Department
Biology
Program
Biology