Each spawn can consist of 1300-1500 bright orange-yellow eggs (about 1.8 mm diameter), with up to five spawns occurring within a year. Adult females build circular floating nests from clipped aquatic plants and release their pelagic, nonadhesive, buoyant eggs on top (Gascho Landis and Lapointe 2010). In the U.S., northern snakehead spawning has been observed to start by the end of April, peak in June, and continue through August (Gascho et al. In its native range, reproductive maturity is typically reached when fish are 2-3 years old (Dukravets and Machulin 1978), but may occur only after one year of growth in some introduced populations (USACE 2011). Upper salinity tolerances have been experimentally determined to be between 15 and 18 ppt (at temperatures of 15-24☌ NSWG 2006). Reduced metabolism and oxygen demand at low temperatures allows this species to survive extended periods of ice cover (Frank 1970, in Courtenay and Williams 2004). Although this species prefers to live in stagnant shallow (30☌, including frost days) than other snakehead species (Dukravets and Machulin 1978, in Courtenay and Williams 2004 Okada 1960). state centroids or Canadian provinces).Įcology: Channa argus is an obligate air-breather, capable of survival in poorly oxygenated waters. * HUCs are not listed for states where the observation(s) cannot be approximated to a HUC (e.g. † Populations may not be currently present. Middle Potomac-Anacostia-Occoquan Middle Potomac-CatoctinĬhester-Sassafras Choptank Conococheague-Opequon Gunpowder-Patapsco Lower Potomac Lower Susquehanna Middle Potomac-Anacostia-Occoquan Middle Potomac-Catoctin Monocacy Nanticoke Patuxent Pokomoke-Western Lower Delmarva Severn Tangierīlackstone River Charles Merrimack Riverīig Sunflower Lower Mississippi-Greenville Lower Mississippi-Helena Lower YazooĬohansey-Maurice Crosswicks-Neshaminy Lower Delaware Middle Delaware-Mongaup-Brodheadīronx Lower Hudson Middle Delaware-Mongaup-Brodhead Rondout Upper Delawareīrandywine-Christina Chester-Sassafras Crosswicks-Neshaminy Lower Allegheny Lower Delaware Lower Monongahela Lower Susquehanna Middle Delaware-Mongaup-Brodhead Middle Delaware-Musconetcong SchuylkillĪppomattox Great Wicomico-Piankatank Lower Potomac Lower Rappahannock Lynnhaven-Poquoson Middle Potomac-Anacostia-Occoquan Middle Potomac-Catoctin Pamunkey Pokomoke-Western Lower Delmarva Rapidan-Upper Rappahannock Shenandoah Stateīig Cache L'Anguille Lower Arkansas Lower Mississippi-Greenville Lower Mississippi-Helena Lower White Lower White-Bayou Des Arc Upper White-Villageīrandywine-Christina Broadkill-Smyrna Chincoteague Choptank Delaware Bay Nanticoke The list of references for all nonindigenous occurrences of Channa argus are found here. Names and dates are hyperlinked to their relevant specimen records. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Interactive maps: Point Distribution Maps The Northern Snakehead is also very similar to the Burbot (Lota lota), another North American native fish species. Additionally, Bowfin can be identified by the presence of a bony plate between the lower jaws (gular plate) and a distinctive method of swimming through undulation of the dorsal fin. Snakeheads can be distinguished from Bowfin by the position of pelvic fins (directly behind pectoral fins in snakeheads, farther back on body in Bowfin) and the size of the anal fin (elongate and similar in size to dorsal fin in snakeheads, short and much smaller than dorsal fin in Bowfin). Morphological differences used for identification between the two are depicted here. Snakeheads (family Channidae) are morphologically similar to the North American native Bowfin ( Amia calva), and the two are often misidentified. Juveniles have a similar color and pattern as the adults. Males are darker in color, and have a broader head, as compared to females (Gascho Landis and Lapointe 2010). It has a somewhat flattened head with eyes located in a dorsolateral position on the anterior part of the head anterior nostrils are present and tubular dorsal and anal fins are elongated, and all fins are supported only by rays (Courtenay and Williams 2004). Overall color is brown with dark blotches. Identification: A long, thin fish with a single dorsal fin running the length of the fish.
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