American Shad (Alosa sapidissima) Energy Availability and Use during Spawning Migration

American shad (Alosa sapidissima) are a numerous and economically important anadromous species native to eastern North America. American shad populations in many rivers have experienced declines due to the impact of dams on migration and habitat loss. American shad do not feed during their adult migration, and experience increasing temperatures, which may reduce energy efficiency. These factors suggest that energy availability may be an important factor during migration, limiting spawning success, survival, and iteroparity, and may be further compounded by migratory delays at dams and fish passage facilities. Previous energetic studies relied on proximate composition analysis which is time consuming and requires lethal sampling and thus can limit sample size. Our study takes advantage of new microwave-based technology (Distell Fatmeter), which allows rapid (< 30 secs) and non-lethal lipid measurements. We will present information on the performance and validation of microwave-based measurements of lipid content in American shad. Additionally, we will report lipid content of 651 American shad at four sampling locations throughout their 2015 migration at 1, 139, 198, and 228 km from the river mouth, and discuss available American shad energy throughout its migration and how differences between early and late-run fish can affect spawning success and iteroparity.