Diet of non-native northern snakehead (Channa argus) compared to three co-occurring predators in the lower Potomac River, USA

Ecology of Freshwater Fish
By: , and 

Links

Abstract

Introductions of large, non-native, carnivorous fishes continue to occur worldwide and represent a substantial management concern to global biodiversity. One of the most recent non-native fishes to successfully establish in North America is the northern snakehead (Channa argus), found in the lower Potomac River catchment. Dispersal of the northern snakehead throughout this system has been well documented since its original discovery in May 2004; however, little is known about the foraging habits of this species and its interactions with co-occurring predators. Here, we quantify northern snakehead diet in comparison with the diets of naturalised largemouth bass (Micropterus salmoides), and native American eel (Anguilla rostrata) and yellow perch (Perca flavescens) collected from tidal freshwaters bordering Virginia and Maryland near Fort Belvoir, Virginia. Over 97% of northern snakehead gut contents were fishes, with fundulid and centrarchid species consumed most frequently. Dietary overlap was biologically significant only between northern snakehead and largemouth bass. Aquatic invertebrates were >10 times more common in native predator diets, reducing dietary overlap with northern snakehead. Ontogenic shifts in adult northern snakehead diet were also detected, which may be explained by optimal foraging rather than true prey specificity. Northern snakehead may be occupying a novel niche based on a piscivorous diet, therefore limiting competition with resident predators in the lower Potomac River. Further research into interactions between largemouth bass and northern snakehead is needed to inform management decisions and understand the ecological impacts of this non-native species.

Study Area

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Diet of non-native northern snakehead (Channa argus) compared to three co-occurring predators in the lower Potomac River, USA
Series title Ecology of Freshwater Fish
DOI 10.1111/j.1600-0633.2012.00563.x
Volume 21
Issue 3
Year Published 2012
Language English
Publisher Munksgaard
Publisher location Copenhagen, Denmark
Contributing office(s) Coop Res Unit Leetown
Description 10 p.
First page 443
Last page 452
Country United States
State Maryland, Virginia
Other Geospatial Fort Belvoir, Lower Potomac River
Online Only (Y/N) N
Additional Online Files (Y/N) N