![]() ![]() Compounding with the overlapping diet, the northern snakehead and largemouth bass share suitable habitat types, causing the two species to hunt for a single source of prey (Love and Newhard 2012). The largemouth bass has a diet that overlaps with the northern snakeheads diet to a biologically significant level, causing a high potential for the two species to become direct competitors (Saylor et al. The introduction of the northern snakehead is predicted to have the highest impact on the largemouth bass, Micropterus salmoides, through competition (Saylor et al. The northern snakehead’s diet has a large potential to become a competitor with several other predatory species that have already become established in the Potomac River, but is likely to affect some species more than others (Saylor et al. Predation effects could extend to other commonly found prey species such as Lepomis spp. Analysis of stomach contents found 15 native species, with banded killifish occurring with a 27% frequency (Odenkirk and Owens 2007). The northern snakehead has not been connected to any declines in native fish species, but possess a high potential to cause negative effects on native species through predation (Odenkirk and Owens 2007, Landis et al. The northern snakehead’s diet consists of, on average, 97% other fish species, which classifies it as a generalist piscivorous predator (Saylor et al. As the population of the northern snakehead expands, the invaded areas will be increasingly exposed to its predatory characteristics (Saylor et al. In large, open water systems the northern snakehead’s dispersal ability will be highly effective, and rapid population growth is predicted to continue in invaded environments (Landis et al. Within the Potomac River, the catch rate of the northern snakehead increased by 950% across the span of a year (Odenkirk and Owens 2007). Once dispersed or introduced to a new environment, the species has a high ability to colonize and increase in population size (Odenkirk and Owens 2007, Lapointe et al. Dispersal was only restricted by physical barriers, occurred across unsuitable habitats, and tended to be in the direction of lower salinity, despite the ability to live in higher salinity habitats (Lapointe et al. Nearly a third of the snakeheads in an observed population had dispersed up to 39km from their primary habitat (Lapointe et al. Dispersal occurs during the pre-spawn months, April to June, most likely due to the snakehead’s desire to find a habitat or a mate (Lapointe et al. The northern snakehead has demonstrated a high ability to disperse long distances (Lapointe et al. Many characteristics are often considered when evaluating the introduction of non-native species, especially the ability to disperse and establish in new areas after an introduction (Lapointe et al. Combined with its ability to live in water with salinity levels between 0-10 ppt, the northern snakehead is predicted to have a large habitable range through most of the United States, down the center of Mexico, as well as southern Canada and Alaska (Herborg et al. In North America, the northern snakehead has been observed to tolerate a wider range of temperatures than it experiences in its native habitat (Herborg et al. Originally discovered in the United States in Maryland in 2002, The northern Snakehead has spread to Virginia, Pennsylvania, New York, and Arkansas (Love and Newhard 2012). The northern snakehead was most likely introduced through the live fish markets (Herborg et al. The northern snakehead has characteristics that are beneficial to its invasion, has a high potential to negatively affect the native species, and has several possible prevention methods that may help control future populations.įrom their native range in eastern Asia, the northern snakehead has been found in Uzbekistan, Kazakhstan, Turkmenistan, and the United States (Landis et al. ![]() Several control methods have been considered to keep the effect of the northern snaked to a minimum (Simberloff et al. This highly piscivorous species poses a serious threat to a broad new range of environments and has become a concern for fisheries along its invaded range (Love and Newhard 2012, Saylor et al. The northern snakehead, Channa argus, is a large freshwater fish native to Eastern Russia, China, and North Korea (Lapointe et al. ![]()
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