Freshwater Drum Ages and Gizzard Shad Ages Files - Freshwater Drum and Gizzard Shad were collected from each site using boat electrofishing. Sampling events took place during June 2016 through May 2017. The sex of each Freshwater Drum from Grand Lake, Elk River, and Kiamichi River was identified as female (F), male (M), immature (I), and, in rare cases, as a hermaphrodite (M/F). Sex was not identified for a subset of Freshwater Drum sampled from Sardis Reservoir (listed as NA: not applicable). The total length was measured in millimeters (mm), and each fish was given unique identification number (ID Tag). The age (years) of individuals was determined through a consensus aging process. Gizzard Shad that were not aged were not given a unique identification number (NA). These fish were released after total length was recorded.

Grand Lake and Sardis Reservoir Hydrology Files - Hydrology for each reservoir was obtained daily historic water-level data for Grand Lake and Sardis Reservoir from the U.S. Army Corps of Engineers monitoring website (http://www.swt-wc.usace.army.mil/). Daily data was recorded from January 1, 1995 through December 31, 3016. Recorded values included pool elevation (meters), storage (acre-feet), reservoir releases (releases: day-second-feet), evaporation (centimeters), and the amount of inflowing water (inflow: day-second-feet).

Elk River and Kiamichi River Discharge Files - Daily riverine discharge data were obtained from the U.S. Geological Survey gages for the Elk and Kiamichi rivers (gages 07189000 and 07335790, respectively). The discharge data (cubic meters per second) was obtained from January 1, 1990 through December 31, 2016.