Beleid en debat

The emergence of Hexagenia limbata mayflies, throughout the Great Lakes and parts of the mid-Atlantic region, is nearly a religious event in angling circles. Each year in early June, these enormous mayflies blanket the landscape, emerging by the billions each night, smothering waterways, riverbanks, roadways and more with thousands of tons of trout-candy biomass. Not long ago, these historic and essential emergences were almost wiped out. By 1970, Hexagenia were gone from large swaths of the Midwest.

The breeding bird population in Germany declined by around 14 million or eight percent over the period between 1992 and 2016, the Federal Agency for Nature Conservation (BfN) said on Wednesday. The "significant decline" in the number of native birds in meadows, pastures and fields has been continuing, according to an evaluation of thousands of data sets by the agency. "In the open agricultural landscapes, the population of breeding pairs has declined by about two million over a quarter of a century," BfN President Beate Jessel said.

The May 2019 newsletter of the Saitama Ecosystem Conservation Society describes how, before the introduction of neonicotinoids in the 1990s, numberless brilliant red akiakane or autumn darter dragonflies could be seen around rice fields in the fall. Experiments by Japanese dragonfly expert Tetsuyuki Ueda of Ishikawa Prefectural University showed how the pesticides reduced the number of surviving dragonfly nymphs to a small fraction, and that the chemicals persist for years in the soil of rice paddy fields.

In the summer of 2010, Henk Tennekes from Experimental Toxicology Services Nederland at Zutphen warned that the accumulation of neonicotinoids in the environment would not only decimate useful insects but also have a knock-on effect on other species, including birds (Curr. Biol. (2011) 21, R137–R139). At the time, Tennekes did not find much support for his views and went on to publish his warnings as a book — The Systemic Insecticides: A Disaster in the Making.

The intensive and extensive application of imidacloprid in agriculture has resulted in water pollution and risks to aquatic invertebrates. However, pure bacteria remediation of imidacloprid in surface water environments has not been studied. Here, we isolated an imidacloprid-degrading bacterium from a water environment, examined its imidacloprid degradation in pure culture and surface water, sequenced its genome, and compared its Clusters of Orthologous Groups (COG) protein categorization with that for another imidacloprid-degrading bacterium.

Freshwater fish species globally are under grave threat according to the latest edition of the International Union for Conservation of Nature (IUCN)’s Red List. In fact, over half of Japan’s endemic freshwater fishes and more than a third of freshwater fishes in Mexico were threatened with extinction, the list of threatended species released on July 18, 2019, said.