Foraging mechanisms of siscowet lake trout (Salvelinus namaycush siscowet) on pelagic prey

摘要: Abstract The reaction distance, angle of attack, and foraging success were determined for siscowet lake trout ( Salvelinus namaycush ) during laboratory trials under lighting conditions that approximated downwelling spectral irradiance intensity (9.00 × 10 8 –1.06 × 10 14  photons m − 2  s − 1 at daytime depths. Siscowet distance in response to golden shiners Notemigonus crysoleucas was directly correlated with increasing light until saturation 1.86 × 10 11 , above which constant within the range tested intensities. At lowest intensity, sensory detection sufficient locate prey 25 ± 2 cm, while intensities increased up 59 ± 2 cm 1.06 × 10 . Larger elicited higher distances than smaller all moving stationary (6.00 × 10 9 ). capture consumption similarly time decreased intensity. majority orientations toward occurred 120° longitudinal axis siscowet's eyes, although among 30° increments along entire not significantly different. developed predictive model will help determine various photic environments identify mechanisms behavior allow low freshwater systems.