An Investigation of Salmonine Reproduction and Factors Limiting Their Production in Sandy Creek, Monroe County, New York

Abstract

Sandy Creek is stocked annually with salmonines by the New York Department of Environmental Conservation. A good recreational fishery has been established during fall spawning migrations but spawning success and juvenile survival have not been researched. My study sought to 1) determine the extent of use of Sandy Creek by adult and juvenile salmonines in 2006 and 2007, 2) assess the creek's potential for sustaining spawning and early life history requirements, and 3) estimate salmonine production in Sandy Creek and potential recruitment to Lake Ontario. Adult Chinook and coho salmon, brown trout and rainbow trout/steelhead were captured and spawned in Sandy Creek. Suitable spawning habitat is generally restricted to the upper reaches of Sandy Creek's east and west branches because bedrock and mud substrates preclude redd construction elsewhere. Habitat and physiochemical conditions are conducive for healthy egg and larval development through winter and spring. Juvenile Chinook and coho salmon, brown trout and rainbow trout/steelhead caught in Sandy Creek were mostly in the east and west branches. Chinook salmon grew rapidly, reaching a total length of ~ 100 mm between emergence in March and out migration to Lake Ontario in June. Coho salmon and rainbow trout/steelhead occupied the headwater region of the east branch of Sandy Creek; few juvenile brown trout were captured. Water temperatures exceeded the upper thermal thresholds (>28 °C) of most salmonine species throughout most of Sandy Creek during July and August. Areal extrapolation of CPUE suggests that Sandy Creek can produce ~ 6,900 juvenile salmonines/creek ha but only the headwater regions provide suitable habitat and physiochemical conditions for salmonine survival year round. Reforestation of the riparian zone and subsequent decreases in soil erosion and summer water temperature would increase salmonine production in Sandy Creek; however, the predominantly bedrock substrate prevents spawning in 90°/o of its main stem. Sandy Creek also supports a healthy, diverse warmwater fish community.