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+ نوشته شده در  یکشنبه بیست و چهارم آذر 1387ساعت 11:38  توسط مجتبی رحیمی 

Mission Statement


Across the United States and around the world, the honey bee populations are mysteriously vanishing. Honey bee colony losses are not uncommon, however, this sort of disappearence is unprecedented. This honey bee colony loss is due to uncharacteristic bee behavior: bees are failing to return to the hive.

Is it an unparalleled natural rythmic ebb in the honey bee population or a portentous prophetic warning of a failing ecosystem? Solving this mystery could have far-reaching effects.

Their decline should draw focus to the critical role the honey bee plays in our food chain and the impact their loss will have on our ecology and economy. As of now, there are several theories posed to explain what has been termed "Colony Collapse Disorder" (CCD).

This site's aim is to keep up with the latest news findings in the U.S. and from around the world on the rapid honey bee population decline; will provide a knowledge environment for honey bee basics, and will serve as an information resource for beekeepers and hobbyists alike to hopefully increase the honey bee population through best beekeeping practices.

Heed the buzz! Beware the silence of the honey bee: HoneyBeeQuiet.

+ نوشته شده در  یکشنبه بیست و چهارم آذر 1387ساعت 11:31  توسط مجتبی رحیمی 

+ نوشته شده در  یکشنبه بیست و چهارم آذر 1387ساعت 11:29  توسط مجتبی رحیمی 

Honey Bee Disappearances: Could Pesticides Play A Role

  • Honey Bee Disappearances Continue: Could Pesticides Play A Role?
    By Linda Moulton Howe
    Earthfiles.com, March 16, 2007
    Straight to the Source


"How much of our food production do we want to turn over to other
countries that might be friendly now and not friendly in the future? The federal government is looking at this and my question is: Are honey bees the canary
in the coal mine? What are honey bees trying to tell us that we humans
should be paying more attention to?"
  - Jerry Hayes, Chief, Apiary Section,
Florida Dept. of Agriculture, Gainsville, Florida


ادامه مطلب
+ نوشته شده در  یکشنبه بیست و چهارم آذر 1387ساعت 11:28  توسط مجتبی رحیمی 

From 1971 to 2006, there was a dramatic reduction in the number of feral honeybees in the US (now almost absent);[11] and a significant, though somewhat gradual decline in the number of colonies maintained by beekeepers. This decline includes the cumulative losses from all factors such as urbanization, pesticide use, tracheal and Varroa mites, and commercial beekeepers retiring and going out of business. However, late in the year 2006 and in early 2007 the rate of attrition was alleged to have reached new proportions, and the term "Colony Collapse Disorder" was proposed to describe this sudden rash of disappearances.[1]

Limited occurrences resembling CCD have been documented as early as 1896,[5][12] and this set of symptoms has in the past several decades been given many different names (disappearing disease, spring dwindle, May disease, autumn collapse, and fall dwindle disease).[13] Most recently, a similar phenomenon in the winter of 2004/2005 occurred, and was attributed to Varroa mites (the "Vampire Mite" scare), though this was never ultimately confirmed. Nobody has been able to determine the cause of any past appearances of this syndrome. Upon recognition that the syndrome does not seem to be seasonally-restricted, and that it may not be a "disease" in the standard sense — that there may not be a specific causative agent — the syndrome was renamed.[14]

+ نوشته شده در  یکشنبه بیست و چهارم آذر 1387ساعت 11:14  توسط مجتبی رحیمی  | 

Radiation: Friend or Foe to Honeybees

For the past several months American beekeepers have become increasingly alarmed as they discover that their bees have inexplicably dissappeared. Since November 2006, beekeepers in 27 states have lost one-quater of their colonies. Similar losses have been reported in Canada, Brazil and in parts of Europe.

A typical bee colony ranges from 15,000 to 30,000 bees and beekeepers consider a loss of up to 20 percent in the offseason to be normal. Regional losses have happened before and are considered normal, however, this is the first nation wide crisis.

Nearly one-third of the human diet comes from insect-pollinated plants, and the honeybee is responsible for 80 percent of that pollination, according to the U.S. Department of Agriculture.

Scientists are calling the mysterious losses Colony Collapse Disorder (CCD). No one is really sure what is happening. Early research indicated that some kind or disease or parasite could be the possible cause of death for the honeybees.

In a recent experiment, USDA's bee scientists irradiated some hard-hit hives and reintroduced new bee colonies. More bees thrived in the irradiated hives than in the non-irradiated ones, suggesting that some kind of disease or parasite was killed by radiation.

German researchers at Landau university have found that mobile phone signals can interfere with bees' "navigation systems".

According to reports, scientists placed "cordless-phone docking units, which emit electromagnetic radiation, into beehives". They found that "in some cases, 70 per cent of bees exposed to radiation failed to find their way back to the hive after searching for pollen and nectar".

+ نوشته شده در  شنبه نهم آذر 1387ساعت 9:56  توسط مجتبی رحیمی  | 

Back in April, right after I decided that it was time to join the tribe of cell phone owners, I heard something on the radio about cell phones being implicated in Colony Collapse Disorder in bees.  Honeybees would leave the hive and disappear, with no sign of dead bees.  The radio report indicated that researchers had found that cell phones were somehow interfering with the bees’ navigation system and preventing them from finding their way home.

Great.  Now my new cell phone was hurting pollinators – my graduate thesis was on pollination biology so conserving plant and pollinator interactions is something that’s been very important to me for a while.

I mentioned it to a few friends, but kept saying that I needed to read the paper – was it the cell phones themselves, or the cell towers?  If the latter, I’d at least only be indirectly at fault.

This week I finally tried to find the paper online.  Wikipedia has a nice site that provides an overview of Colony Collapse Disorder and has links to primary documents as well as media reports.

The good news is that the research in question had nothing to do with cell phones – a good reinforcement of the idea that it always pays to examine the research directly.  In two sets of experiments, scientists at the University of Koblenz-Landau in Germany took cordless phone bases (not cell phones) and put them right in honeybee hives.  These emit electromagnetic radiation all the time. 

In the 2005 study, four of 16 hives experienced Colony Collapse Disorder during the experiment, but one of these was a control hive with no cordless phone present.  The researchers recorded lower mean honeycomb weights and areas, and longer return times, for hives that had the phone bases than for the control hives, but these differences were not statistically significant (and, as my grad school advisor would say, therefore they really weren’t differences).  One of the main suggestions for improvement that the authors had was that next time around they should not place the exposed and control hives in blocks; instead they should distribute them randomly.

In 2006 they did so, and they added a couple of other new features to the study.  They made some physical barriers to create hives that had only 50% of the electromagnetic exposure that other exposed hives had, and now that the hives with phone bases were interspersed with the controls, they made some metal barriers to keep the electromagnetic waves from affecting the controls.  The effectiveness of these barriers sounds a bit sketchy and is not explained well in their report (both of these studies are only available in English as rough translations from the German provided by the authors); in fact, one of their main suggestions for future research is to actually measure the intensity of the electromagnetic radiation within each hive, which seems pretty critical.

Their sample size was tiny again – five fully exposed hives, three partially exposed hives, and eight controls.  They found similar patterns again – the return rates that they recorded for the controls were better than for the exposed hives (not much difference between the different intensity of exposure), but the differences were not statistically significant.  They then developed an index that combined not just how many bees returned but how long it took them to get there, and finally got a significant result – the fully exposed group had worse performance than the controls.  But it seems like they may have done quite a few statistical tests without providing a correction for multiple comparisons (the more tests you do, the greater the chance that one will turn up significant even if it’s not biologically meaningful, so you should have a higher standard for significance when you’re running a bunch of tests using the same data).  On the other hand, a larger sample size would have increased their power to detect significant differences, so the trends that they were seeing might actually stand up with a larger study.

What does this all mean?  To me it suggests that a statistically robust study on the impacts of electromagnetic radiation on bee behavior is warranted.  At the same time,  having a radiation source right in the hive seems extreme, but it also seems plausible that a cordless phone base in the hive might be comparable to the radiation emitted by some high tension powerline nearby – I don’t know enough about what levels of electromagnetic radiation bees would be likely to run into naturally.  It also means that while I don’t need to carry around direct guilt about my cell phone for the moment, electromagnetic radiation may still be taking a toll on wildlife.

The researchers themselves have been open with the press about the fact that they are not claiming that their study provides any kind of explanation for Colony Collapse Disorder – the original reporter that got the whole firestorm started never even contacted this lab.  Instead, the researchers suggest that Americans worry more about the contributions that herbicides and genetically modified crops may make toward honeybee declines than about electromagnetic radiation's effects.

The Colony Collapse Disorder Working Group’s Frequently Asked Questions page explains that they don’t think that bee feed, bee antibiotics, bee use (pollination vs. honey production), or source of queens are causal factors.  Instead, they are focusing on chemicals, pathogens, parasites, poor nutrition, stress, and lack of genetic diversity as possible culprits.  They also indicate that it’s more likely than not that there isn’t a single cause but rather that a combination of factors is weakening honeybee stocks.

So, I’m off the hook on my phones (cell and cordless) for the moment, but unfortunately there is no remedy for the disappearing bees yet, or for the crops and wildflowers that depend on them.

+ نوشته شده در  شنبه نهم آذر 1387ساعت 9:50  توسط مجتبی رحیمی  | 

Honeybee_Pollen.jpg

 

+ نوشته شده در  شنبه نهم آذر 1387ساعت 9:49  توسط مجتبی رحیمی