Blue Sucker Cycleptus elongatus mark-recapture data in the Colorado River, Texas from 2016-2026

This data release contains mark-recapture and associated environmental data for blue sucker (Cycleptus elongatus) collected in the lower Colorado River, Texas, from 2016 through 2026. The release includes capture records from 16 field events, combined into 13 primary sampling occasions for analysis, across up to 40 electrofishing sites, with information on sampling dates, site identifiers, individual PIT tag numbers, capture and recapture histories, total length measurements, sex observations when available, and records of capture-related mortalities used for right-censoring. It also includes sampling effort information by occasion and site, time intervals among occasions, and streamflow and air-temperature covariates assembled for each sampling occasion or inter-occasion interval, including discharge metrics, hydrologic classification variables, and prior-year thermal and flow metrics used to support demographic modeling. It also includes daily discharge records for USGS gages 08160400 and 08158000, hourly air temperature at Austin-Bergstrom International Airport, a table of dams in the Colorado River basin, and an R script that rebuilds every derived table from the raw input files and reproduces the main analyses of the companion article.