Diel feeding and movement activity of Northern Snakehead Channa argus

By: , and 

Links

Abstract

Understanding the diel activity of a species can shed light on potential interactions with other species and inform management practices. To understand the diel activity of Northern Snakehead Channa argus, feeding habits and movement patterns were observed. Two hundred seventy-three Northern Snakehead were captured by boat electrofishing during May and June of 2007 and 2008. Their gut contents were extracted and preserved. The level of digestion of each prey item was estimated from fresh (1) to >50% digested (4) or empty (5). Random forest models were used to predict feeding activity based on time of day, tide level, date, water temperature, fish total length, and sex. Diel movement patterns were assessed by implanting Northern Snakehead with radio transmitters and monitoring them every 1.5 h for 24 h in both March and July 2007. Movement rates were compared between March and July and among four daily time periods. Independent variables accounted for only 6% of the variation in feeding activity; however, temporal feeding patterns were apparent. No fresh items were observed in guts between 12:30 and 7:30 am, and the proportion of empty stomachs increased at the end of May coinciding with the onset of spawning. Overall, fish moved greater distances during the July tracking period compared to March. Fish showed a greater propensity to move during daylight hours than at night during the March tracking period. A similar but nonsignificant (P > 0.05) pattern was observed in July. Movement and feeding data both indicated greater activity during daylight hours than at night, suggesting that Northern Snakehead is a diurnal species. Based on our preliminary findings, we hypothesize that a) diurnal species are more susceptible than nocturnal species to predation by Northern Snakehead and b) Northern Snakehead are more likely to compete for food with diurnal than nocturnal predators.

Study Area

Publication type Conference Paper
Publication Subtype Conference Paper
Title Diel feeding and movement activity of Northern Snakehead Channa argus
DOI 10.47886/9781934874585.ch6
Year Published 2019
Language English
Publisher American Fisheries Society
Contributing office(s) Coop Res Unit Leetown
Description 13 p.
Larger Work Type Book
Larger Work Subtype Conference publication
Larger Work Title American Fisheries Society symposium 89
Conference Title The First International Snakehead Symposium
Conference Location Alexandria, VA
Conference Date Jul 17-19, 2019
Country United States
State Maryland, Virginia
Other Geospatial lower Potomac River
Google Analytic Metrics Metrics page
Additional publication details