UNO-Report zum Insektensterben veröffentlicht

Der aktuelle UNO-Report zum Artensterben der Wildinsekten  bestätigt   langgehegte Befürchtungen  und  widerspricht allzu  einfachen monokausalen Ursachen, wie

 

Deutsche Welle ( EN) berichtet:

UN report warns risk to bees and other pollinators threatens human food supplies

The UN’s first ever report on biodiversity warns that bees, butterflies and other pollinators are at risk of extinction. Such a development would threaten human food supplies and cost hundreds of billions of dollars.

Bees, butterflies and other pollinators are at risk of extinction, which could eventually disrupt global food supplies and cause hundreds of billions of dollars worth of economic damage, according to a massive UN report by a scientific body.

The report, which was assembled over two years, draws from many scientific studies but does not include any research of its own. was approved by a congress of 124 nations meeting in Kuala Lumpur on Friday.

 

Bienensterben CSIRO Forschungsprojekt mittels Mikrochip Honey bees pollinate one-third of the food we eat – including fruit, vegetables, oils, seeds and nuts

Many wild bees and butterflies have been declining in abundance, occurrence and diversity at local and regional scales in Northwest Europe and North America,“ said an assessment by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES).

In addition, more than three-quarters of the „leading types of global food crops“ such as apples, mangoes and cocoa rely to some extent on animal pollination for yield and quality, according to the report, which was approved by a congress of 124 nations meeting in Kuala Lumpur on Friday.

„Pollinator-dependent species encompass many fruit, vegetable, seed, nut and oil crops, which supply major proportions of micronutrients, vitamins, and minerals in the human diet,“ according to the IPBES.

Simon Potts deputy director of the Center for Agri-Environmental Research at Britain’s Reading University and co-chairman of the report said many commonly consumed foods are at risk.

Raupe Kokon Schmetterling Butterflies are also key pollinaters, but are at risk

„Pretty much nearly all your fruits and many of your vegetables are pollination-dependent,“ said Potts.

Bee colonies collapse

Several years ago bee colonies across Europe and the United States suddenly began dying in a still unexplained plague dubbed „colony collapse disorder.“

The number of managed bee hives in the United States plunged from 5.5 million in 1961 and dropped to less than 2.5 million in 2012. The number of hives is back up slightly, to 2.7 million but worries about the colonies‘ overall health persist.

„The variety and multiplicity of threats to pollinators and pollination generate risks to people and livelihoods,“ the report stated. „These risks are largely driven by changes in land cover and agricultural management systems, including pesticide use.“

Bildergalerie IUCN Bedrohte Tierarten Hummingbirds are also key pollinaters, but at risk

Pesticide use poses both general and specific problems for pollinators and crops, according to the report.

„Pesticides, particularly insecticides, have been demonstrated to have a broad range of lethal and sub-lethal effects on pollinators in controlled experimental conditions,“ the report said.

But it cautions that more studies are needed on the effects on pollinators in the wild.

Herbicides kill off weeds, which are useful for wild pollinators, according to the report.

As much as $577 billion worth of food output depends on pollinators, according Zakri Abdul Hamid, who chaired the IPBES report

„Pollinators,“ he said, „are critical to the global economy and human health.“

 

Die kanadischen CBS-wissenschafts-News berichten auf gleicher UN-Report-Grundlage:

Weiterlesen

Forscher haben geklärt, wie Wespen den Weg zurück zum Nest finden

aus DRADIO Forschung vom 12.2.2016

Wenn Wespen ihr Nest verlassen, dann fliegen sie erst einige Male dorthin zurück, bevor sie auf Nahrungssuche gehen. Schon lange ist bekannt, dass sie diese „Lernflüge“ stets in der gleichen Form fliegen, und zwar in immer größer werdenden Bögen vom Nest weg. Wenn sie von der Futtersuche zurückkommen, fliegen sie ähnliche Bögen, bevor sie ihr Nest wieder erreichen.

Lernflüge der Wespen

Lernflüge von Wespen

 

Jetzt haben Forscher aus Deutschland und Australien herausgefunden, wie die Wespen den Weg zurück zum Nest finden. Sie haben die Insekten in Australien mit Hochgeschwindigkeitskameras gefilmt und ihre Flugrouten am Computer ausgewertet. Demnach schießen Wespen ein mentales Foto ihres Nestes und der Umgebung, wenn sie in einem Bogen darüber fliegen. Sie speichern dann ihre Position und die Richtung zum Nest ab. Kommen sie von der Nahrungssuche zurück und deckt sich die Umgebung mit der eines abgespeicherten Fotos, können sie die Richtung zum Nest rekonstruieren. Landmarken am Boden, wie etwa Felsen, helfen bei der Orientierung. Die Studie ist im Fachmagazin „Current Biology“ erschienen. [Jst]

Leider ist der vollständige Artikel nur in englisch verfügbar .

Zitiert nach:

Stürzl et al., How Wasps Acquire and Use Views for Homing, Current Biology (2016), http://dx.doi.org/10.1016/
j.cub.2015.12.05