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Pollinators and Pesticides - A look at modern Neurotoxins

Pesticides and Pollinators - A look at Modern Neurotoxins (ppt file)- Slide presentation by Gary Rondeau prepared for 2014 SAVE the BEES event.  ppt file has comment for many slides that will aid in understanding the presentation.  PDF version does not have comments.

It’s not just the bees, it’s the birds

July 9, 2014

Research out of the Netherlands, to be published tomorrow (7.10.2014) in the prestigious journal Nature, demonstrates a strong correlation between the  decline of insect-eating bird species and presence of neonics in the environment.  Comparable declines in bird species did not take place in the same areas before neonics were used, nor does it take place today even on farmland where bird habitat is undermined but neonic contamination is lower. Co-authors Caspar A. Hallmann, Ruud P. B. Foppen,Chris A. M. van Turnhout,Hans de Kroon & Eelke Jongejans speculate that neonics deplete food sources for several bird species through the sustained poisoning of non-target insects:

“Our results suggest that the impact of neonicotinoids on the natural environment is even more substantial than has recently been reported and is reminiscent of the effects of persistent insecticides in the past. Future legislation should take into account the potential cascading effects of neonicotinoids on ecosystems.”



Please Report Dead Bees

July 7, 2014

In the wake of two recent bumblebee die offs in Eugene and Portland resulting from pesticide poisoning, it is especially important to report suspected pesticide poisonings to the Oregon Department of Agriculture.

If you are a beekeeper who finds more than 50 dead bees in any single area or  colony, contact the Oregon Department of Agriculture: or (503) 986-6466.


Pollinator Peril – Research Highlights

March 20, 2014

Two years ago I made poster for our educational bee event called Keeping our Bees Alive – The Challenges.  At that time we knew that the neonicotinoid insecticides were likely a big problem, but we had a hard time figuring out why sometimes the bees seemed to tolerate the pesticides and other times bee colonies with a modest exposure could collapse.  The multi-factor nature of the problem was apparent, and is illustrated in that poster.

This year I concentrated on what we have learned in the last two years that can help us solve the colony collapse puzzle.  This year, Pollinator Peril – Reserach Highlights presented research that shows how the neonicotinoids interact syynergiysticly with common bee pathogens, making the bees much more suseptible to natural diseases.  This research goes a long way to explaining why there can be such a variable response to neonicotinoid exposure, since it is usually the pathogens that kill the bees in colony collapse, not the neonicotinoids directly, and the pathogens need to be present as well as the insecticide for devestating losses.

The poster can be viewed here: Pollinator Peril – Reserach Highlights

Live links to the original research and referenced papers are provided below.

1.Aufauvre J, Biron DG, Vidau C, Fontbonne R, Roudel M, et al. (2012)  Parasite-insecticide interactions: a case study of Nosema ceranae and fipronil synergy on honeybee. Sci. Rep. 2: 326.
2.Cornman RS, Tarpy DR, Chen Y, Jeffreys L, Lopez D, et al. (2012) Pathogen Webs in Collapsing Honey Bee Colonies. PLoS ONE 7(8): e43562. doi:10.1371/journal.pone.0043562
3.Di Prisco G, Cavaliere V, Annoscia D, Varricchio P, Caprio E, et al. (2013) Neonicotinoid clothianidin adversely affects insect immunity and promotes replication of a viral pathogen in honeybees PNAS2013, doi:10.1073/pnas.1314923110
4.EFSA. 2013.Conclusion on the peer review of the pesticide risk assessment for bees for the active substance imidacloprid . EFSA J 11:3068.
5.Feltham H, Park K, and Goulson, D. (2014)  Field realistic doses of pesticide imidacloprid reduce bumblebee pollen foraging efficiency.  Ecotoxicology   doi: 10.1007/s10646-014-1189-7
6.Gill RJ, Ramos-Rodriguez O, Raine NE (2012) Combined pesticide exposure severely affects individual- and colony-level traits in bees. Nature 491: 105-108.
7.Krupke CH, Hunt GJ, Eitzer BD, Andino G, Given K (2012) Multiple Routes of Pesticide Exposure for Honey Bees Living Near Agricultural Fields. PLoS ONE 7(1): e29268. doi:10.1371/journal.pone.0029268
8.New York Times, March 29, 2013.  Mystery Malady Kills More Bees, Heightening Worry on Farms.
9.New York Times, January 29, 2014.  Migration of Monarch Butterflies Shrinks Again Under Inhospitable Conditions.
10.Pettis JS, Lichtenberg EM, Andree M, Stitzinger J, Rose R, et al. (2013) Crop Pollination Exposes Honey Bees to Pesticides Which Alters Their Susceptibility to the Gut Pathogen Nosema ceranae. PLoS ONE 8(7): e70182. doi:10.1371/journal.pone.0070182
11.Rondeau G.  (2013) Time-dependent toxicity of imidacloprid on bees and ants.
12.Tennekes HA, Sánchez-Bayo F. (2013) The molecular basis of simple relationships between exposure concentration and toxic effects with time. Toxicology 309:39-51.
13.White, G. The problem with pesticides: it’s the birds and the bees.  The Beekeepers Quarterly 111 March 2013

Tell EPA: Step Up and Protect Bees

March 13, 2014

Send a message to the Environmental Protection Agency through this Pesticide Action Network campaign to get EPA administrator Gina McCarthy to ban “neonics” now rather than waiting until 2018, which is the current plan.

The data is there:  there is no reason to let bees and native pollinators continue to die for the next four years.

Good News for Oregon’s Bees and More to Do

February 28, 2014

This from John Jordan, Communication Director for Beyond Toxics:

Eugene’s City Council Wednesday night voted to ban the use of neonicotinoid pesticides on city property. Council Resolution 5101 also expands the current Pesticide-Free Parks program and requires all city departments to adopt the same IPM standards and protocols as the City’s Parks and Open Space Division.

The Eugene City Council resolution, the only one of its kind in the nation, passed by unanimous consent in a council work session. The language of the resolution specifically includes a strong concern for children’s health as well as protecting bees and a host of other pollinators in Eugene’s environment.

Click here is the text of the ordinance.


Now if we could only stop selling neonics as well: but there are steps in the right direction.  This past Monday, February 24, the Save Oregon Pollinators Act (HB 4139-3 amended) passed 27-2.  The bill now goes to the Governor’s desk where he is expected to sign it into law.

Important:  The bill requires all pesticide applicators to take a course and pass a test on Bee Health and Pesticides, and establishes a Task Force instructed to bring further bee protection legislation to the 2015 Legislature.

Thus the bill takes proactive steps to prevent pesticide operators’ performing uneducated acts of label violation like that which killed 50,000 bumblebees in a mall parking lot in which linden trees were sprayed while in bloom last year.

Thank you, Jerry’s!

February 13, 2014

Jerry’s Home Improvement Center in Eugene responded to concerns of beekeepers regarding the sale of neonicotinoid insecticides by examining the data and taking action– placing products containing these pesticides on the back shelves of their garden area, along with pamphlets outlining the dangers of these pesticides to pollinators.

Thank you to locally owned Jerry’s! We need more responsible home and garden retailers to follow their example and that of retailers in the UK who refuse to sell these pesticides.

More Data Implicates Fungicides in Colony Collapse

November 30, 2013

A study by University of Maryland and US Department of Agriculture researchers just published in PLOS ONE indicates that fungicides in pollen weaken the ability of honeybees to withstand nosema–thus making honeybee colonies more susceptible to Colony Collapse Disorder.

This work adds to the research on the toxic effects of “neonics” on bees by indicating important additional stresses on  honeybees :

1) Bees are made susceptible to colony collapse disorder by foraging pollen  in crops NOT directly sprayed with pesticides, but with low levels of several different pesticides resulting from drift.  Thus saving our bees demands more stringent  spray regulations than those currently in practice.

2) Fungicides, which had been assumed to be harmless to bees, weaken bees’ immune systems even with very low exposure.  Far from being harmless, they are a key player in colony collapse.

3)  It is difficult to pin the cause of colony collapse disorder on a single toxin because modern bees are regularly exposed to a large number of pesticides in the pollen they forage– with complex synergistic effects.

Since PLOS ONE is an open access journal, you can review this essay and its data at the link above.

In order to save our honeybees, we need not only to get “neonics” out of our pesticide arsenal, but radically cut back on fungicide use. This is a special challenge in the Pacific Northwest given our wet climate– but the survival of our bees, both native and honeybees, demands it.

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