We published a study of 99 small Swiss streams in Aqua & Gas which reveals that most of these streams have significant ecological deficits, limiting their ability to serve as habitats for animals. In over 70% of the streams studied, pesticide-sensitive insect larvae and other small animals are partially missing. Statistical analyses show that these aquatic organisms are particularly affected when the stream bed structure and morphology have been altered or when the catchment area has a high proportion of agricultural land.