Overige insecten

This thesis by Sebastian Stehle analyses the agriculture–environment linkages for pesticides at the global scale and it thereby contributes to a new research frontier in global ecotoxicology. The overall findings substantiate that agricultural insecticides are potential key drivers for the global freshwater biodiversity crisis and that the current regulatory risk assessment approaches for highly toxic anthropogenic chemicals fail to protect the global environment.

High brown Fritillary butterfly - Once widespread it is now reduced to around 50 sites and threatened with extinction; Great Crested Newt – a sharp decline with only around 75,000 existing across the country; Hen Harrier – One of Britain’s most threatened birds of prey with only around 600 breeding pairs left; Hazel Dormouse – declined by one third in recent years and it is not extinct in 17 counties; Barbastelle Bat – widespread decline and fewer than 5,000 remaining; Ringed plover – only 5,600 breeding pairs remaining; Water vole – populations have dropped by 90 per cent in recent years;

In Deutschland gibt es immer weniger Bienen, immer weniger Hummeln, immer weniger Schmetterlinge. Überhaupt gibt es immer weniger Insekten! Das haben Forscher aus Krefeld herausgefunden. Das ist eine Stadt im Bundesland Nordrhein-Westfalen. 25 Jahre lang haben die Forscher an bestimmten Orten Insekten gesammelt, ihre Art bestimmt und die Tiere gewogen. Das Ergebnis der Forscher: In dieser Zeit stellten sie einen Rückgang an Insekten von bis zu 80 Prozent fest. Gesammelt haben die Forscher vor allem in Nordrhein-Westfalen.

Neonicotinoid insecticides like thiacloprid enter agricultural surface waters, where they may affect predator-prey-interactions, which are of central importance for ecosystems as well as the functions these systems provide. The effects of field relevant thiacloprid concentrations on the leaf consumption of Gammarus fossarum (Amphipoda) were assessed over 96 h (n = 13-17) in conjunction with its predation on Baetis rhodani (Ephemeroptera) nymphs. The predation by Gammarus increased significantly at 0.50-1.00 microgram/L.

Der baden-württembergische Ministerpräsident Winfried Kretschmann hat einen dramatischen Rückgang der Fluginsekten festgestellt – und beruft sich dabei auf seine Windschutzscheibe. Früher sei die nach langen Autofahrten voll von Insekten gewesen, sagt er. Heute, so ist ihm aufgefallen, klebe da kaum noch etwas dran. „Voll“ und „kaum“ sind zwar keine wissenschaftlichen Kriterien, doch der gelernte Biologe Kretschmann liegt mit seiner Einschätzung nicht daneben. „Der Rückgang an Insekten ist in der Tat dramatisch“, sagt der Kirchheimer Vogelkundler und Insektenforscher Wulf Gatter.

Bäche und kleine Flüsse in Landwirtschaftsgebieten sind massiv mit Giftstoffen aus der Landwirtschaft belastet. Dies zeigte ein Bericht des Gewässerforschungsinstituts EAWAG. Die Konsequenzen sind dramatisch: Eine kurze massive Erhöhung von Giftstoffen im Wasser während der Spritzzeit der Kulturen kann eine ganze Generation von Insektenlarven eines Jahres auslöschen. Das ist deshalb bedenklich, weil sich in solchen Gewässern viele Larven von Insekten entwickeln: etwa Eintagsfliegen, Mücken oder Libellen.

I miss seeing the back end of a bug. This summer I sensed a disturbance of some sort. There were hardly any ladybirds, almost no butterflies (only the odd cabbage white) and barely a wasp. Very, very odd. I noticed early on that the orchard would crop moderately (as opposed to well); I put this down to the slow spring and accompanying lack of pollinators.

Some birds pop up when you least expect it. On August bank holiday I went for a walk to my coastal patch, along with assorted relatives and a very boisterous dog. Bird-wise, apart from a high-tide roost of a thousand redshanks along the river Brue, things were relatively uneventful. But as we were strolling back to the car, a small bird flew up onto a protruding twig along a hedgerow, and posed in a way that made its identity virtually certain. A glance through my binoculars confirmed that it was indeed a whinchat (Saxicola rubetra).

When I started with Save Our Seine, I was surprised by an unusual topic on every board agenda: "Things we have learned from nature." With recent news about mosquitoes, malathion, and the cosmetic use of herbicides, I would like to share things I learned from nature in 1981 that had a profound impact on me. Manitoba was in the midst of an outbreak of western equine encephalitis (WEE). Like West Nile virus, WEE is spread by infected mosquitoes. A DC-6 aircraft was brought in to quickly blanket the city with Baygon to reduce the mosquito population.