Verspreiding en achteruitgang van de grote modderkruiper in een historisch perpectief

.The weather loach (Misgurnus fossilis) has the highest protection status in Europe and The Netherlands is of great importance to this species. In the second half of the 20th century, this fish strongly decreased. In 70% of the onekilometer grid squares known before 1980 and examined again in the period until 2008, the species was not found anymore. Natural occurrence of weather loach is attached to biotopes in the flood plains of rivers and streams. With the arrival of man, the river landscape became cultivated for agricultural use by constructing dikes and digging ditches. The present habitat of the weather loach is predominantly in agricultural areas (67%). An important cause of the decline of the weather loach is large-scale land development. In the current situation the remaining populations of the weather loach are almost restricted to old watercourses that have escaped development. In many of these areas the survival of the weather loach is at stake. Conservation of the species in these areas requires urgent protective easures.m