River provides the habitat for eighteen species of native fish as well as lamprey and black flounder. Native fish species present include Cran's bully, upland bully, climbing galaxias, pouched lamprey, shortjaw kokopu, torrentfish and New Zealand smelt. Although not present in high numbers, brown and rainbow trout are found in the river and there have also been reports of catfish being present. Other aquatic species Other aquatic species present in the river include Longfin and Short-finned eels and koura. New Zealand freshwater mussels are also present in the river, although these have been shown to be in decline. Invertebrate fauna The Whanganui river and its tributaries are also home to a variety of invertebrates such as mayflies, stoneflies and caddis flies. Flora The Whanganui River basin contains a variety of flora species, much of which can be characterised as a broadleaf and podocarp forest; understory species include crown fern (Blechnum discolor), and a variety of other ferns and shrubs. River boats In 1892 Alexander Hatrick was contracted by Thomas Cook & Son to carry tourists to Pipiriki on the paddle-steamer PS Waimarie, the journey was "The Rhine of Maoriland" tourist route into the interior of New Zealand. The river boat subsequently carried mail, passengers and cargo. PS Waimarie operates on the lower stretches of the river, including dinner cruises to Avoca Hotel at Upokongaro and trips to Hipango Park for overnight camping. On 18 June 2010 the Adventurer 2 river boat embarked, attempting to make the voyage to Taumarunui. The first voyage to Taumarunui in 82 years. The Adventurer 2 now offers this trip to tourist as an historic alternative to jet boating and canoeing the river. Though in low water flows it cannot make it all the way to Taumarunui. River boat landings The Whanganui River was the supply artery for the early communities along its banks. River boats used to ply the river, and also into the Ohura River and Ongarue Rivers unless these routes were log jammed after floods. Between 1891 and 1958 the Alexander Hatrick Riverboat service operated on the Whanganui River. The paddle-steamer Wairere ordered from London and shipped in sections then assembled in Whanganui in late 1891. It is said that Taumarunui was the highest reach of the Whanganui River that was navigable by river boat. The river flow was managed by the "Wanganui River Trust Board" which built containing walls to direct and