Proceedings of the New Zealand Ecological Society (1972) 19: 120- 142

Lakes Manapouri and Te Anau: Applied ecological studies of shoreline vegetation at lakes Manapouri and Te Anau, Fiordland: Part 2: The lake edge flora—habitats and relations to lake levels.

Research Article
P. N. Johnson  
  1. Department of Botany, University of Otago, Dunedin

At non-rocky sites on the shorelines of Lakes Manapouri and Te Anau floristic composition was recorded for one-foot intervals of elevation above and below lake level. Mean daily levels recorded since 1932 have been analysed to find the longest periods of submergence and emergence experienced at each level. A hypothesis that species distribution is governed by extremes of submergence and emergence is supported by the similar periods recorded at the limits of each species at both lakes. At rocky sites at Lake Manapouri the relationship between lake level fluctuation and species ranges is modified by exposure to wind and waves. The means by which species limits are determined by lake level fluctuation and the effect of the lake on reproductive biology are discussed. A full list of species is appended, with information on their habitats.