Overige insecten

Eight English rivers are polluted with neonicotinoid pesticides

Rivers in England are contaminated with powerful insecticides, new testing has revealed, increasing concerns over the impact of the toxic chemicals on fish and birds. Eight rivers in England are heavily contaminated with neonicotinoid pesticides. Two of the rivers, the Waveney on the border between Norfolk and Suffolk, and the Tame in the West Midlands, had an “acute level” of pollution, according to tests conducted by the Environment Agency last year.

Het Ctgb en de neonicotinoïden of hoe een door Henk Tennekes beschreven ecologische ramp werkelijkheid werd

Het bewijs dat een nieuw type pesticide zeer schadelijk is, stapelt zich op. Maar de autoriteiten luisteren liever naar wetenschappers die op schoot zitten bij de agrochemische industrie. Het instorten van bijenkolonies in heel de Verenigde Staten en Europa. De massale sterfte van kikkers in meertjes in de Sierra Nevada. De woekering van infecties onder de Japanse rijstvis. De kaalslag onder vleermuizen. De dramatische daling in het aantal weidevogels. Al dit leed brengt de Nederlandse toxicoloog Henk Tennekes in verband met een nieuw type pesticiden, de neonicotinoïden.

The Resilience of the Bee Hive

Neonicotinoid insecticides are based on the natural toxin nicotine, and are of particular concern because they bind virtually irreversibly to the nicotinic-acetylcholine receptors in the insect’s nervous system. Many observations show that the longer the exposure time, the less amount of total chemical is needed to kill the insects; in other words, the lethal exposure concentration decreases with exposure time.

Primaire oorzaak van de insectensterfte is het gebruik van neonicotinoïde bestrijdingsmiddelen

De oogst van onder meer appels, peren en aardbeien dreigt te halveren als de insectensterfte doorzet. Wetenschappers waarschuwen dat de sector dit honderden miljoenen kan kosten. 'De dreiging voor de bij en andere insecten is zeer serieus,' zegt Koos Biesmeijer. Hij is hoogleraar Natuurlijk Kapitaal aan de Universiteit Leiden en wetenschappelijk directeur bij Naturalis. Een van de grote oorzaken van de insectensterfte is het gebruik van bestrijdingsmiddelen. 'In ons landje willen we heel veel en dat gaat niet altijd goed met de biodiversiteit', zegt Biesmeijer.

Insects and insectivores on the brink of extinction in the Adirondacks

In September, the U.S. Fish and Wildlife Service denied a petition to put the Bicknell’s thrush (Catharus bicknelli) on the federal list of endangered species. The Bicknell’s is a medium-size (6-7.5 inches) thrush—brown on the back with a white, spotted underside—that dwells in dense balsam-fir forests in high elevations in the Adirondacks. Following is a primer on other wildlife in trouble in the Adirondack Park.

White-nose syndrome is killing bats by the millions in the U.S.

Blake Sasse, nongame mammal program coordinator for the Arkansas Game and Fish Commission updated Commissioners at today’s regularly scheduled meeting on the status of white-nose syndrome, a disease that is killing bats by the millions in the U.S. “You hear about CWD with deer, and we’re all concerned with it, but I’m equally concerned about WNS in our bats,” Sasse said. According to Sasse, the disease actually is a fungus that grows on the bats during hibernation and causes them to wake prematurely.

Paul Kirkland: How the plight of the butterfly may hit Scotland’s wild flowers

Much attention has been given to the plight of bees because of their importance as pollinators of major crops. But there is growing evidence that butterflies and moths – many of which have suffered dramatic declines in recent years – play an important role as specialist pollinators of some of our favourite wild flowers. A Swedish study recorded pollen on the bodies of three-quarters of butterfly species examined with some individuals carrying up to 350 grains.

Die Waldameisen verschwinden in der Schweiz

Die Waldameisen stehen unter Druck: «In den vergangenen 40 Jahren dürfte die Zahl der Ameisenhaufen in Rheinfelden und Umgebung um rund 60 bis 80 Prozent zurückgegangen sein», erklärt Urs Jost. Der 70-jährige Rheinfelder ist durch einen Dokumentarfilm auf die kleinen Krabbler und ihre grossen Probleme aufmerksam geworden. Bereits 1976 hatte der WWF vor einem «alarmierenden Rückgang der Waldameisen» gewarnt. Seither hat sich die Lage noch verschlechtert.

Insect decline: the biodiversity of the entire world is at stake

Bees and butterflies are experiencing widespread population decline, creating public concern in recent years. Data collected in Germany suggest that it’s not just bees and butterflies at risk: insect populations overall have plummeted by more than 75 percent since 1989. Scientists have known about the population decline for several years. However, they didn’t know how many species were declining, and they didn’t expect it to be happening so fast.