by CHARLIE VANDEN HEUVEL
Columbia Gorge Beekeepers Association
A controversial topic to be sure! The news media as well as social media are quick to suggest pesticides are responsible for a slurry of detrimental effects on our environment.
Since the beginning of time, humans have striven for a few basic needs — somewhere to live and most importantly somewhere to live. Nature works in a delicate balance facing the greatest challenge in the battle to maintain food supplies that are plentiful and safe.
Some plants, animals or organisms can threaten the food supply. These are considered pests. An example in the mid-19th century the effects of the Irish Potato Famine evolved. Massive crop losses result in over 1.5 million deaths as starvation ensued.
In the honey bee world, the cry continues to be how pesticides are wiping out the entire population of the bees. If not pesticides, it is miticides (chemicals designed to mitigate the Varroa destructor mite).
This article is not intended to be a complete account of research, but rather a perspective toward balance in information.
Researching the effects of chemicals, or drugs, on the human body can be divided into two segments: 1) Acute exposure, and 2) Sublethal exposure.
In June 2014 a major bumble bee death occurred in North Eugene due to the application of pesticides on linden trees. A massive die off of bumble bees occurred in 2013 in Wilsonville from neonicotinoid pesticide (Safari).
The difference between Acute and Sublethal can be illustrated by the tragic dropping of a nuclear weapon on Hiroshima. Medical research of the surviving population and their subsequent generations continues to this day. These studies are vast and intensive insights into the effects of that occurrence.
On the other hand, sublethal exposure to low doses of radiation are more challenging. Our bodies’ physiology comes into play. What other processes are going on that are not instigated by the radiation?
Back to our honey bees — the number one killer of the honey bee today is the Varroa destructor mite. This mite migrated from Southeast Asia across Europe landing in Florida in 1987. Thus far, in spite of significant research, the mite appears to be winning the battle devastating honey bee colonies across our nation.
Last year as commercial beekeepers arrived from across the country to pollinate the almond orchards, unfortunately a sixty-two percent loss of colonies was identified.
Why? The predominate factor came down to Amitraz, a miticide that was overused, poorly dosed; resulting in the Varroa developing resistance, enabling the mites to overwhelm the colonies.
Although numerous studies have been performed in relation of pesticide exposure to the honeybee and its effects, these studies are weak in articulating the entire story.
Most pesticide research is conducted by exposing the bees in the lab to a sugar syrup solution with the pesticide mixed in. Yet, when similar studies are performed in the field, the same exposure does not seem to hold up.
Varroa destructor mites, lack of pollen and cold temperatures inside the hive have a significant effect on the honey bees. In other words, attempting to assess the impact of pesticides, especially sublethal exposure, is hampered by other body issues, rendering it difficult for the analysis to arrive at a clear conclusion.
Honey bees forage for several elements: nectar (that is dehydrated into honey by the bees), pollen, propolis (resin from trees), and water.
Pesticide exposure comes from nectar, pollen and water. Yet, is the amount (dose) significant to deleteriously affect the honey bee?
The honey bee has an element called Vitellogenin. This element is similar to the human white blood cell in its duty to combat bacteria, fungus, viruses and even cancer. In the honey bee an additional function of Vitellogenin is the detoxification of pesticides.
Honey bee enzymes come into play toward detoxifying pollutants. The bees have fewer amounts of detoxification genes compared to pest insects. On the other hand, the bees compensate through their highly social behavior.
Gut microbiota, a group of microorganisms within the bee’s gastrointestinal tract, may also have a role in the detox of pesticides.
Detoxification mechanisms in honey bees involve multiple genes and pathways. The response of P450 genes plays a significant role in direct detoxification of insecticides. Bees may become tolerant to insecticides.
Honey bee colonies operate not so much on an individual basis but a colony defense basis.
Their antennae, where the majority of senses are housed, provide significant information on temperature, sound, salt, sweetness, carbon dioxide and more. Do the bees have a sense of which flora have pesticides?
The challenge to quantifying the effects of exposure to pesticides and miticides becomes challenging to discern the period of time the exposure, along with the route of exposure being orally or dermally. Like many current research studies today, the advance in techniques and equipment enable researchers to arrive at an improved assessment of lethal as well as sublethal exposures to chemicals.
It seems the jury remains in discussion rather than an affirmative conclusion on pesticides verses honey bees. What can be said is, any chemical in our environment has to have some impact on humans, animals and insects. The question yet to be resolved is, how much?
Consider dispensing a few dollars toward Project Apis m in support of their funding (https://www.projectapism.org/partners/#give).
The Columbia Gorge Beekeepers Association meets on the third Wednesday of each month, http://www.gorgebeekeepers.org/, at the Hood River Extension, 2990 Experiment Station at 6:00 PM. A different subject is presented by an Entomologists or
experienced beekeeper. All are welcome. Visitors may attend in person or via Zoom. You may reach out to the club for login information - admin@gorgebeekeepers.org. You may also enjoy a visit to the Hood River Extension to view the three bee hives maintained by the Columbia Gorge Beekeeping Club and financially by the Hood River Master Gardeners, Klahre House and the Columbia Gorge Beekeepers Association.
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