Both pollen quantity and pollen quality in modern agricultural crops has changed, and this is well documented in the agricultural literature.


For example, my father pioneered field corn in the Yellowstone Valley of Montana in the 50s.  We flood irrigated, and I hated irrigating corn - if you had to walk down the rows when during pollen shed, it was like a yellow snowstorm.  For three years, we conducted pollen sampling in the corn belt - IL, IN, NE.   We had to clip a minimum of 50 tassels, bag, dry, and shake out, just to get a sufficient sample to analyze - about a teaspoon of pollen from 50 tassels!


The only corn that was shedding much pollen was varieties of sweet corn.   Field corn was not attractive to bees, some varieties of sweet corn were, and one could watch the pollen falling as the bees collected it.



A literature search clearly showed that the corn researchers knew and had documented that the amount of pollen being shed was diminished in modern corn varieties.  What was not as clear was whether the protein content, which typically is low in corn pollen, was even lower now? 


About the same time, we sampled melons in CA - whole fields full of melons in bloom.  We had 100 ft long tents straddling 10 rows of melons, and the bees couldn't collect enough pollen to even be captured by pollen traps (most loads were too small to be scraped off as the bee returned).  Same could be said about the quantity of nectar.  We did a lot of repeated sampling and hand-capture of bees to get even a tiny sample - even worse than corn.  Again, as a kid, we had the typical farm garden with lots of melons.  Those melons didn't lack for pollen.


Then we did some work with a USDA scientist working on new varieties of soybean.  Out of 14 new varieties, only a few were even attractive to bees.


The problem is - growers and the researchers working on new varieties of crops are selecting for traits that affect the growers profit - ever-bearing, larger, more robust, insect and disease resistance.  What's not in the equation - testing to see if the new varieties are:


1) Attractive to pollinators such as bees,
2) Alter the quantity of pollen and nectar available to bees,
3) Affect the quality (e.g., protein content/sugar content) of pollen and nectar.


It's no wonder beekeepers don't like corn and melons.  Corn was never much of a food source for bees, but melons were.  In our melon tent trials, we saw that the hundreds of colonies placed around every one of the multiple fields where we had tents lost ground in terms of nectar/honey and pollen stores.  If they came in with their hives heavy with resources when placed on the melons, they usually left lighter (unless there was something else nearby to offset the poor resources from melons).  If they were light, they had to be fed just to keep them alive and active.


 
My point is that new crop varieties are not tested for attractiveness and resource quantity and quality to pollinators.  After all, most growers would prefer crops that don't need pollinators - one less variable to consider, less cost.


My utopian viewpoint would be that new crop varieties should be required to show that they have sufficient attractiveness, quantity, and quality of pollen to sustain or benefit pollinators - if not, the varieties couldn't be registered for use.  


Just as we don't permit pesticides to be used that are unacceptably hazardous to bees, crops that yield poor quality food to bees may be just as harmful, perhaps even worse in terms of overall bee health.  In essence, what may appear to be a bountiful and beautiful fields in bloom may be the bee equivalent of junk food, making the concept of fat bee, skinny bee one of healthy bee versus unhealthy anorexic bees (except that it's not an eating disorder, it's a starvation disorder).



None of this has to invoke CO2 levels, climate change - it's all a result of us fiddling with nature.  Whether accomplished by old fashioned selection and hybridization or the newer genetic modification - the effects on pollinators have not been considered.


Finally, work we did more recently for the crop dust research consortium, where we deliberately exposed bees to lethal quantities of neonicotinics, showed that even rather severe bees losses could be off-set by supplemental feeding.   Most of our test colonies rebounded from the initial kill in early summer, but only those that we fed after the exposure incident did well when overwintered.


All of which leaves me of the opinion that one of, if not the biggest problem affecting the health of our bees, is a lack of abundant, high quality food resources.   We all know that bees like a diverse floral resource.  We found that canola is still attractive to bees, yielding generous amount of pollen and nectar; yet the bees still sought out and brought back pollen from other plant sources - including other crops and wildflowers.  Backyard beekeepers know the value of a diverse floral resource - look at how successful many urban beekeepers are - where bees have access to gardens and ornamental plants.   Commercial beekeepers, especially the migratory ones, don't have that luxury.  Which raises the question - in terms of numbers of bee colonies (not number of beekeepers), where is the biggest problem and what is the most cost-effective solution.  My guess is that programs encouraging planting of pollinator friendly plants is a great idea, but effectively a drop in the bucket when considering the the majority of the colonies in the USA are commercial.  Patches of wildflowers are good PR, but how big is the benefit overall?  What would be the effect of planting more pollinator friendly crops?  My guess is that the result would dwarf that of the bee friendly plants and produce a much larger improvement in both bee health and the profitability of beekeeping for the professional beekeeper and the majority of the hives kept in the USA.  Obviously, a combination of increasing diversity and improving the quality of the primary crop/floral resources would be ideal - but where would we get the biggest and fastest improvement?  


Finally, we need to start watching our language.  Obviously, there are more small scale beekeepers than commercial beekeepers in the US.  By contrast, the majority of the colonies of bees in the USA are commercial.  When we read reports by BIP and the media that annually,  X% (in recent years we've seen numbers in the mid- to high 30s, even 40s) of the nation's beekeepers lost their bees - we need to be sure to note, that statement does not apply to the percent of colonies lost!  In fact, that number applies to small scale beekeepers.   By BIPs own data, commercial beekeepers in recent years have held to a relatively steady annual loss of about 25% of their colonies. Let's be sure we are talking about improving the health of the colonies of bees in the US, not the emotional status of the nation's beekeepers.  Clearly, BIP data shows that the so-called feedlot (commercial) beekeepers as a group manage to sustain their colonies at an annual loss level that compares to examples such as Tom Seeley's feral colonies.  More than anything else, BIP data shows that in terms of annual loss of bee colonies, we're doing about as well as can be expected.  Overall though, we need to do a better job of training the new and small scale beekeepers - the so-called nation's beekeepers.



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