Insecticiden

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.

Recent studies have shown that arthropods—insects, arachnids and other small, hard-bodied animals—are in trouble, from massive declines in the biomass (total weight) of flying insects to regional extinctions in a number of insect groups, such as butterflies. A new large-scale study across a number of habitats in Germany has found that the problem may be more extensive than previous research suggests.

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.

Steve Gillam, Starved Rock volunteer Tom Williams and Starved Rock State Park natural resource coordinator Lisa Sons exchanged jokes and friendly chitchat as they trudged over a muddy path along a field edge, wetland and woods at Matthiessen State Park. They were not seeing many birds, despite sunny, breezy conditions and diverse habitat, during their after-lunch hike over their territory in the Starved Rock Audubon Society Christmas bird count. And they said they had not seen many birds in the morning among the oak trees and canyons in the Matthiessen Dells area.

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.

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