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Differential Stress Responses In Fish From Areas Of High- And Low-Predation Pressure, Culum Brown, Carolyn Gardner, Victoria Braithwaite
Differential Stress Responses In Fish From Areas Of High- And Low-Predation Pressure, Culum Brown, Carolyn Gardner, Victoria Braithwaite
Aquaculture Collection
We subjected fish from regions of high and low levels of predation pressure in four independent streams to a mild stressor and recorded their opercular beat rates. Fish from low-predation areas showed higher maximum, minimum and mean opercular beat frequencies than fish from high-predation regions. The change in opercular beat frequency (scope) was also significantly greater in fish from low- than in fish from high-predation regions. Under normal activity levels, however, low predation fish showed a reduced opercular beat frequency, which may be indicative of reduced activity levels or metabolic rate. Opercular beat frequency was negatively correlated with standard length …
Effects Of Predation Pressure On The Cognitive Ability Of The Poeciliid Brachyraphis Episcopi, Culum Brown, Victoria A. Braithwaite
Effects Of Predation Pressure On The Cognitive Ability Of The Poeciliid Brachyraphis Episcopi, Culum Brown, Victoria A. Braithwaite
Sentience Collection
Variable levels of predation pressure are known to have significant impacts on the evolutionary ecology of different populations and can affect life-history traits, behavior, and morphology. To date, no studies have directly investigated the impact of predation pressure on cognitive ability. Here we use a system of replicate rivers, each with sites of high- and low-predation pressure, to investigate how this ecological variable affects learning ability in a tropical poeciliid, Brachyraphis episcopi. We used a spatial task to assess the cognitive ability of eight populations from four independent streams (four high- and four low- predation populations). The fish were required …