Will the Expansion of Northern Snakehead Negatively Affect the Fishery for Largemouth Bass in the Potomac River (Chesapeake Bay)?

Abstract

A modeling study was conducted to determine if the expansion of invasive northern snakehead Channa argus could negatively affect the largemouth bass Micropterus salmoides population size in Potomac River (Chesapeake Bay). Current distributions for both species were generated using catch records. Northern snakehead was not widely distributed during the study period and occurred mainly in upstream areas of tributaries. Many of these areas were moderately or highly suitable habitats for largemouth bass. Of sites where juvenile largemouth bass were collected, 10.6% were associated with northern snakehead. Using population modeling and measured predator–prey interactions, we determined that this level of co‐occurrence would result in a 3.8% reduction in largemouth bass population size. This prediction is consistent with current observations that indicate there has not been a negative trend in the largemouth bass fishery. As co‐occurrence was increased in the model, however, the negative impact of northern snakehead on largemouth bass monotonically increased. The time required for such increases in northern snakehead distribution is not known. If northern snakehead continues to expand its range in the absence of control measures, then our population model, with its assumptions, predicts a 35.5% reduction in the abundance of largemouth bass in the Potomac River. Received February 6, 2012; accepted June 7, 2012

Conservation of Black Bass Diversity: An Emerging Management Paradigm

“…), and fishes (Steinhart et al. , ; Love and Newhard ) all impact black bass populations in different ways. However, perhaps the most immediate threat to the conservation of black bass diversity is the introgressive hybridization that results from the introduction of non‐native congeners.…”

“…Non native species are widely recognized as a threat to native aquatic biodiversity (Cambray 2003), and non native aquatic plants (Slipke et al 1998;Dotson et al 2013), mollusks (Phelps 1994;Strayer et al 2004), and fishes (Steinhart et al 2004a(Steinhart et al , 2004bLove and Newhard 2012) all impact black bass populations in different ways. However, perhaps the most im mediate threat to the conservation of black bass diversity is the introgressive hybridization that results from the introduction of non native congeners.…”

Spatial Variability and Macro‐Scale Drivers of Growth for Native and Introduced Flathead Catfish Populations

“…; Green et al. ; Love and Newhard ). Quantifying the spatial variability in growth of a species within both its native and introduced ranges and understanding large‐scale growth patterns may provide further insight into how a species might respond to future introductions or range expansions made possible by changing environmental conditions.…”

Identification and Location of Testes in the InvasiveChanna argusCantor (Northern Snakehead)

“…2012). However, Love and Newhard (2012) demonstrated that if co-occurrence of largemouth bass and northern snakehead increases, then it is possible in the absence of northern snakehead control largemouth bass abundance may decline.…”