The Impacts of Atlantic Salmon Stocking on Rainbow Trout in Barnum House Creek, Lake
By Jason P. Dietrich, James N. Bowlby, Bruce J. Morrison, Nicholas E. Jones
Journal of Great Lakes Research, Volume 34, Issue 3, 2008, Pages 495-505, ISSN 0380-1330, DOI: 10.3394/0380-1330(2008)34[495:TIOASS]2.0.CO;2.
We compared the impacts of stocking age-0 Atlantic salmon (Salmo salar) at high and low densities, and no stocking on abundance and growth of age-0 rainbow trout (Oncorhyncus mykiss) in Barnum House Creek, Ontario during 1993 to 2005. A similar stream, Shelter Valley Creek, was chosen as an appropriate reference stream where age-0 Atlantic salmon were not stocked. The catches of age-0 rainbow trout in Barnum House and the reference stream were highly correlated (r = 0.96) during years when no stocking occurred; however, this relationship did not persist in years when Atlantic salmon were stocked. The catch of age-0 rainbow trout in Barnum House Creek was significantly lower under both high (P = 0.00026) and low (P = 0.011) density Atlantic salmon stocking treatments compared with the no stocking treatment. The catches of age-0 rainbow trout and age-0 Atlantic salmon were negatively correlated in Barnum House Creek (r = -0.63). The length of age-0 rainbow trout in Barnum House Creek was depressed significantly (P = 0.004), under the high intensity Atlantic salmon stocking treatment, but not under the low intensity treatment (P = 0.20). In contrast, the length of age-0 rainbow trout in Shelter Valley Creek was unchanged over the same period. Restoration stocking of Atlantic salmon in Lake Ontario tributaries may impact rainbow trout abundance and growth.
Keywords: Rainbow trout; Atlantic salmon; stocking; density; growth; interaction