Adult and juvenile paddlefish in floodplain lakes along the lower White River, Arkansas

Abstract

Eleven floodplain lakes in the lower White River, Arkansas were sampled using a boat electrofisher and gill nets during periods of river connection (April–May 2004) and disconnection (June–July 2004 and 2005). Environmental characteristics, including water quality and lake morphometrics were concurrently measured in each lake. Average measures of connectivity were calculated for the preceding 5-year period. Of the 11 lakes sampled, 7 lakes contained paddlefish. A total of 44 paddlefish were observed during the study, but only 1 was observed during the period of river connection. Eye-fork lengths ranged from 348– 1040 mm (n = 38). Paddlefish ranged in age from 3–19 years (n = 27). Paddlefish were more likely to be found in long narrow floodplain lakes that connected to the river early in the year. Paddlefish catch per unit effort increased as lake surface area, dissolved oxygen level, and variability in the start date of connection increased. Our research indicated that both juvenile and adult paddlefish use White River floodplain lakes, despite the risk of being isolated in lakes for long periods or being prevented from accessing riverine spawning habitat.