Age-0 Channel Catfish Ictalurus Punctatus Growth Related to Environmental Conditions in the Channelized Missouri River, Nebraska

作者：Hogberg N P^*; Hamel M J; Pegg M A

来源：River Research and Applications, 2016, 32(4): 744-752.

DOI：10.1002/rra.2890

• regulated rivers
• flow regime
• fish growth
• AIC modelling

Large river paradigms suggest that natural flow regimes are critical for maintaining instream habitats and promoting production and growth of native aquatic organisms. Modifications to the Missouri River, Nebraska, within the past 100years have drastically reduced shallow water habitat, homogenized the flow regime, and contributed to declines in several native species. Despite drastic flow modifications, several metrics of the Missouri River's flow regime still vary across years. We related age-0 channel catfish growth to environmental conditions in the channelized Missouri River, Nebraska, between 1996 and 2013 using an information theoretic approach. Growth rate was most influenced by growing season duration and duration of discharges below the 25th percentile of 30-year daily Missouri River discharges. Periods of low water may be important for juvenile growth because of channel modifications that limit critical shallow water habitat during higher within-bank flows. Exclusion of peak discharge and peak discharge timing in the best model to predict growth is counter to conventional thoughts on river fish responses to hydrological conditions but may be reflective of the general lack of high-magnitude flooding during the majority of our study. Future efforts to relate juvenile fish growth to environmental conditions can provide guidance for water management in the Missouri River and other regulated North American rivers.

• 出版日期2016-5