This item informs us that we havelost an astounding 96% of the bumble bee population. The quoted causation is at best rubbishexcept for the use of pesticides.
We already know that Bayer’s cornseed pesticide is disastrous and implies a particularly damaging pathway forall bees. Effectively, the pollencollected on and by the bees act as a pesticide collector to produce acumulative load that eventually concentrates with the queen to kill her. This is a purely mechanical problem thatcould never have been predicted and plausibly acts over a wide range ofpesticides and has simply never been understood in this way before.
Thus a pesticide naturally safeat low dosages turns into a hive destroying cancer that eventually kills thequeen.
In fact the characteristics of acolony collapse syndrome (CCS) conform to the sudden demise of the Queen andits sister larvae (who are all fed pollen).
The populations can recover veryquickly and we will still have plenty of refugia out there.
Yet this can only begin with acomplete review of all pesticide protocols for any sign of cumulative toxicityin the food provided to queens.
Bees in freefall as study shows sharp US decline
From the GuardianJan 4, 2011
The abundance of four common species of bumblebee in the
Bumblebees are important pollinators of wildplants and agricultural crops around the world including tomatoes and berriesthanks to their large body size, long tongues, and high-frequency buzzing,which helps release pollen from flowers.
Bees in general pollinate some 90% of the world'scommercial plants, including most fruits, vegetables and nuts. Coffee, soyabeans and cotton are all dependent on pollination by bees to increase yields. Itis the start of a food chain that also sustains wild birds and animals.
But the insects, along with other crucialpollinators such as moths and hoverflies, have been in serious decline aroundthe world since the last few decades of the 20th century. It is unclear why,but scientists think it is from a combination of new diseases, changinghabitats around cities, and increasing use of pesticides.
Sydney Cameron, an entomologist at the Universityof Illinois, led a team on a three-year study of the changing distribution,genetic diversity and pathogens in eight species of bumblebees in the US .
Bycomparing her results with those in museum records of bee populations, sheshowed that the relative abundance of four of the sampled species (Bombus occidentalis, B. pensylvanicus, B. affinis and B. terricola) had declined by up to96% and that their geographic ranges had contracted by 23% to 87%, some withinjust the past two decades.
Cameron's findings reflect similar studies acrossthe world. According to the Centre for Ecology and Hydrology in the UK , three ofthe 25 British species of bumblebee are already extinct and half of theremainder have shown serious declines, often up to 70%, since around the 1970s.Last year, scientists inaugurated a £10m programme, called the InsectPollinators Initiative, to look at the reasons behind the devastation in theinsect population.
Cameron'steam also showed that declining species of bee had higher infection levels of apathogen called Nosema bombi andlower genetic diversity compared with the four species of bee that were not indecline – B. bifarius, B. vosnesenskii, B. impatiens and B. bimaculatus.
The N. bombi pathogen is commonlyfound in bumblebees throughout Europe but until now has been largely unstudiedin North America . The infection reduces thelifespans of individual bees and also results in smaller colony sizes.
The reduction in genetic diversity seen in thedeclining bees means that they are less able to fight off any new pathogens orresist pollution or predators. "Higher pathogen prevalence and reducedgenetic diversity are, thus, realistic predictors of these alarming patterns ofdecline in north America, although cause and effect remain uncertain,"Cameron wrote today in Proceedings of the National Academy of Sciences.
Insects such as bees, moths and hoverfliespollinate around a third of the crops grown worldwide. If all of the UK 's insect pollinators were wiped out, the dropin crop production would cost the UK economy up to £440m a year, equivalent to around 13% of the UK 's incomefrom farming.
The collapse in the global bee population is amajor threat to crops. It is estimated that a third of everything we eatdepends upon pollination by bees, which means they contribute some £26bn to theglobal economy.
Other identified causes of bee decline includeparasites such as the bloodsucking varroa mite and viral and bacterialinfections, pesticides and poor nutrition stemming from intensive farmingmethods.
"Pollinator decline has become a worldwideissue, raising increasing concerns over impacts on global food production,stability of pollination services, and disruption of plant-pollinatornetworks," wrote Cameron. "In accordance with the goals of the UnitedNations convention on biological diversity to reduce the rate of species lossby 2010, such efforts to elucidate the causes and ecological impacts of bumblebee decline, in co-ordination with informed conservation strategies, will go along way to mitigating further losses."
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