Maybe you have some insight
In general, I personally don’t care too much for unsolved mystery movies or similar TV shows. I like clear endings with the villain being taken away in restraining cuffs. However, when it comes to bee colony mysteries, I have been forced to learn to accept lingering unknowns. They simply will not go away. The particular question is clearly there, but the answer is not. I simply cannot avoid these pesky answerless questions. Ergo, this may not be a satisfying article for you or me. This discussion is all questions with precious few answers.
What are the salt and mineral needs within the colony?
During passing years, I have studied the beekeeping literature, I have watched bees forage at water sources, I have written articles that contained no answers, and I have spent many hours — just thinking about honey bee colonies and their “wetness” needs. After all, I am the beekeeper. I am supposed to help my bees meet all their colony needs. It’s my job. Right?
Water and moisture (humidity) needs in the colony are common management considerations. Innumerable ways to supply water to thirsty bees abound in the literature and within presentations at bee meetings. Keeping your bees from your neighbor’s saltwater swimming pool is an annual issue. Admonishments like “Never let your water source run dry” are consistent advice from confident authorities.
Yet, during winter months, beekeepers strive to help bees remove “excess” moisture from the dormant colony to prevent excessive colony wetness. What was not enough during the summer is now too much during the winter season. Water needs vary widely throughout all four seasons. But all beekeepers know this: In some quantity, bee colonies absolutely require water. That much we seem to agree on.
Out of all the myriad questions we could ask about water needs, I am going to choose an old, tired one: “Why do bees frequently collect water from foul water sources?” The frequent hypothetical answer is that bees need a complex mixture of salts and microminerals. Finally, I am at the point where I can pose my query: If they are truly visiting these fetid sources for salts, how much salt and minerals do my colonies need? By assuming that the competent foragers can find natural sources, am I unintentionally ignoring my colonies’ “salt” needs? I can’t derive a clear answer.
If I may use some of my article space, I would like to offer some of my experiences that have forced this question to remain with me for many decades.
Event One: One summer day many years ago, after a rain shower, I was in the Ohio State forestry facility where several hundred pine seedlings had been potted. Great numbers of plants were bunched outside in rows on plastic tarpaulins. Blue fertilizer water had been used to douse the plants, and excess blue water had drained from the pots’ drain holes and had pooled on the tarp.
Honey bees were everywhere, imbibing the blue fertilizer water. Some of the bees were even in the pot drain holes and in the soil mixture. (I temporarily named them “mining honey bees.”) The foraging bees were in large enough numbers to be annoying to forestry workers. All the while, readily available rainwater pools were everywhere. Foragers were clearly choosing the fertilizer water source over recent rainwater. I made photos, but I have not seen these pictures in many, many years. Now, I only have my memory and the remaining unanswered question. What colony need(s) drove those foragers to that source? Salt and mineral availability?
Event Two: Again, decades ago, during the Africanized Honey Bee invasion years, I was visiting an Arizona cattle feedlot. At that time, the cattlemen were concerned about the potential effects of “Killer Bees” on their large herd of confined cattle. The owners pointed out a significant number of honey bees foraging on liquid feedlot runoff, much of which was cattle urine. (It’s hard to write that information in a positive light.) Water troughs were readily available, but foragers chose this despicable source. Clearly, the bees wanted something other than plain water.
As far back as 1900, investigators suspected honey bee foragers’ preference for urine before pure water was because of the minerals that it contained. In the August 2010 issue of this magazine, Zachary Huang wrote: “Other species of honey bees (e.g., Apis dorsata, A. cerana) have been observed to forage in urinals or open restrooms in Asia.”
Event Three: Years ago, while visiting our family farm, again I was at the cattle pasture. Near the water trough was a mineral salt block in a large, plastic pan. The liquid brine that accumulated in the pan was ringed with bees collecting concentrated salt water. At the time, I thought how sick that salty water would make me if I consumed it. I didn’t notice any foragers at the water trough that was nearby.
I could list more observations that I have made through the years, but I feel that I have made my point. At some level, our bees need salt and minerals that they harvest from their environment. I don’t know how they find these unique sources. I don’t know how much energy they must expend to gather salt, and I do not know the quantity of their seasonal needs. Lau reported findings suggesting that some water foragers actually specialize in salt collection.1
Go ahead. Search the web. There are abundant references to the salt needs of bee colonies. And it’s not only our honey bees. Due to their annoying habit of siphoning perspiration from our wet brows, we have even named some hover flies “sweat flies” and we have a species of native bees that we call “sweat bees.” You know the reason behind those names.
While slogging through the web citations, I came across this comment posted by TB, “An old beekeeper once told me that if you are out around your hives and the bees are landing on you for no reason, they are looking for salts. As you sweat, you lose salt through your skin, and this is what the bees want. I have found that when my bees run out of salt, they do start doing that. So now I keep salt out for them all season long. The old beekeeper’s suggestion to me was just put out table salt for them in a dry spot and they will use it.”
Personally, I have never observed honey bees foraging on me for my salty sweat, but neither can I say that I have specifically looked for it either. However, I would not be shocked if there is some relevance here.
Old beekeepers are always perceived authorities. Many years ago, I, too, had an old beekeeper tell me to add a tablespoon of salt to my sugar syrup and that the bees would take it more readily. I was not able to document that salted syrup was more attractive to foragers, but I have always remembered the recommendation — especially when I am watching bees seemingly collect salty water.
Indeed, some old issues of “ABC & XYZ of Bee Culture” have specific recommendations for supplying salt to colonies. In all instances, the amount of salt was small. “The Hive and the Honey Bee” has a short section on the salt and water balance mechanism in honey bees.
In all our lectures and discussions, when listing the materials bees collect, we …