River Tywi these fish to over in weight. In summer and autumn there is also a substantial run of Atlantic salmon ("Salmo salar"). In May the Tywi has a run of the rare and protected twaite shad ("Alosa fallax") and allis shad ("Alosa alosa"). The Tywi also contains brown trout, eels, pike, and a variety of small fish species, and is home to brook lampreys, river lampreys and sea lampreys. The Tywi has the distinction of having accidentally produced by far the biggest fish ever taken on rod and line in fresh water in Britain. This was a sturgeon ("Acipwienser sturio") weighing
Rachel Carson National Wildlife Refuge have extensive vernal pool habitat that would benefit several Species of Concern. Coastal marshes, bays, tidal creeks, and rivers support diverse shellfish and finfish populations. Sunfish ("Lepomis" species), creek chub ("Semotilus atromaculatus"), cunner ("Tautogolabrus adspersus"), golden shiner ("Notemigonus crysoleucas"), common mummichog ("Fundulus heteroclitus"), American eel ("Anguilla rostrata"), and white sucker ("Catostomus commersoni") abound. Brook trout ("Salvelinus fontinalis") and brown trout ("Salmo trutta") are stocked in rivers and estuaries each year. The Ogunquit River sustains alewife ("Alosa pseudoharengus"), blueback herring ("Alosa aestivalis"), pollock ("Pollachius virens"), bluefish ("Pomatomus saltatrix"), longhorn sculpin ("Myoxocephalus octodecimspinosus"), and winter flounder ("Pleuronectes americanus"). The Webhannet River has