The moor is an important withy-growing area with remaining areas in permanent neutral grassland. The site contains some of the most diverse aquatic plant communities in the country. Field ditches, particularly between withy beds, may be hand cleaned resulting in outstandingly rich communities. A rich invertebrate fauna, with many nationally and locally rare species is associated with the botanical diversity of the ditches. This fauna includes the rare soldier fly Odontomyi a ornata , two notable water beetles Rhantus grapii and Hydaticus transversalis , a notable terrestrial beetle Donacia dentata and the dragonflies Brachytron pratense and Coenagrion pulchellum .
West Moor is the only known Somerset site for the nationally rare weevil Bagous nodulosus .