How much does difference in weight does a drop of rain on a worker bee make? Can they fly in rain?
So what’s the weight of a raindrop? We in Western Washington (geographical base of the SnoKing Beekeepers Assn.) know that drops of precipitation range from the fine mist settling on us while we stand in heavy fog to huge splats on our windshields when driving.
If you try to search the internet, you quickly discover that many can not work in metric and give ridiculous estimates because they can’t work with milligrams.
https://hypertextbook.com/facts/1999/MichaelKodransky.shtml was about the best quick source I found: Michael Kodransky shows his calculations and says “Following these steps, the smallest mass of a raindrop produced during a drizzle is then 0.004 mg and the largest produced during a heavy storm is 300 mg.” Michael Kodransky -- 1999
So a mist drop landing on a worker bee just adds 4 mg to the bee’s 121 mg, about 3% extra, however, a huge storm splat adds more than double the bee’s weight. In a direct hit, the bee doesn’t have a chance.
This could explain why bees hesitate to fly in the rain.
Note: In case you try to research this on the internet, it is full of outright misinformation, and then you run into trouble just trying to get the size (volume) of a drop of water. Physical scientists will give you the volume and weight of a drop of water massed in a lab under standard conditions, whereas medical/pharmaceutical/ biotechnology sources are defining a drop of water as .05 grams, 20 drops to the ml. Why? Because the latter needed standardization for calculations involving drops of different solutions. I (Eli Ocheltree) became aware of this when working in biotech. As Wikipedia explains it, “Pharmacists have since moved to metric measurements, with a drop being rounded to exactly 0.05 mL (50 μL, that is, 20 drops per milliliter). In hospitals, intravenous tubing is used to deliver medication in drops of various sizes ranging from 10 drops/mL to 60 drops/mL.” https://en.wikipedia.org/wiki/Drop_(unit)
Sorry this blog entry is so long. I'll keep the next one shorter.