SELECTION AND BINDING TO SPECIFIC HABITAT S BY BLACKFLIES AND THE SIGNIFICANCE THERE OF FOR THE PRESERVATION OR REESTABLISHMENT OF NEAR-NATURAL BODIES OF RUNNING WATER

Selection and binding to specific habitats by blackflies and the signi ficance there of for the preservation or re-establishment of near-natu ral bodies of running water. The choice of locality for rite depositio n of eggs by blackflies is given for a number of species (among them S imulium costatum FRIEDER., S. nolleri FRIEDER, S. ornatum MG. and Pros imulium tomosvaryi (END.). The females react to changes in the environ ment of running waters, whether the changes are due to the dynamics of the body of water or the influence of Man. Evidently the signals asso ciated with the structures of the habitat or subhabitat are the factor s which lead to the certain orientation towards and selection of habit -at by each species, since the females posses a concept. Are certain s ignals (characters) absent, then the eggs will not be recognised and a colonisation of the water through eggs will nor: take place, Referenc e pictures, specific Co certain natural environments, types of running waters, ecological and habitat models or patterns developed for pract ical application, are compared and contrasted. Reference is also made to the special importance of invariable signal factors, which have not been specially influenced so far through the activities of man in the vicinity of running waters. It is thought that current pattern belong to such invariable structures, It is recommended that a more thorough analysis of the habitat patterns of individual species be made, so th at bodies of running waters can be either specifically protected or re -naturalised with theses species in mind.