Pollen is Vital to Honey Bee Health and Survival

I have returned to Manchester from three days ‘down South’ in London and Surrey, having had my eye surgery, which was a great success. The surgeon said something like “Stephen’s perfect” when describing the state of my eye, post surgery. I suppose it could have been “Stephen’s is perfect” (referring to his work rather than the walrus he’d worked on), but either way, it was encouraging. I saw daffodils coming into flower near Oxshott station. Beekeepers often like to declare spring early, but as far as I’m concerned, we are still in the middle of winter. Anyway, the sight of early blooms has prompted me to consider how pollen is vital to honey bee health and survival.

Peter Bray of Airborne Honey

When I met Peter Bray of Airborne Honey in NZ in January 2018 (can it really have been five years?!) one thing I asked him about was ‘heroes’ or, at the very least, people he admired. As he is a Kiwi, I was not expecting him to give top billing to an Aussie, but life is full of surprises. Here is what he said:

“I’d have to say Graham Kleinschmidt. He was my tutor at Queensland Agricultural College, and he was a very far thinking and foresighted individual. He initiated research of his own, and I think he also inspired a character called Doug Somerville, who wrote a book called “Fat Bees, Skinny Bees. The contents of that book had their genesis very much in Graham’s work on nutrition of bees and measuring crude protein levels in pollen.

You’ve got the issue in Australia, where most of the honey plants didn’t evolve with honey bees. They’ve evolved by providing pollen and nectar as rewards to native pollinators like moths, beetles and native bees, parrots and so on. For European honey bees to come along and firstly find the pollen attractive, and secondly find it nutritious with the right amino acids, was fundamental to their survival. Then there was the discovery that bees can mine their own bodies to feed protein to their young during a dearth. It’s a law of diminishing returns because if they can’t get good nutrition and feed the subsequent generation you get into a downward spiral. He nominated a number, a point of absolute no return, where the bees were done for. As the protein in the bees drops, so does their life expectancy, so at some point you just get a complete collapse of the population. 

Pollen Quality

When I came back to New Zealand in 1980 from Australia I looked around and thought that we don’t have a problem here, but subsequently we did because we now have monocultures in this region. We also have bees working on high yielding native plants but then failing the following Spring, and it’s primarily because of the poor quality of the pollen they are getting. Nosema impacts on this too because it is a disease of the gut, and it prevents the bee from absorbing the nutrition it needs. If you have poor nutrition and a poor digestive tract, it’s a double whammy. If you’ve got Nosema, but you have really good pollen resources you can get them over that hump; through a combination of eating the good pollen and mining their own bodies they can get to the next generation, and get past it.

Some types of pollen are fantastic, like gorse. It’s a Winter source, and any bees we had on sites near gorse would come into Spring absolutely booming. Broom is a similar plant with a similar quality of pollen. It doesn’t have to be a varied diet so much as having a really good source of quality pollen. Willow is another good one. Guess what? All three are European plants. Our main one here is Salix fragilis – we call it Crack Willow.”

Pollen, Nectar and Water

I always say that, for honey bees, nectar is their carbohydrate and pollen provides their protein. There’s plenty more going on in pollen than protein, with other goodies such as lipids (fat), vitamins and minerals. As Doug Somerville points out in his excellent, and frequently re-read book, if bees experience a lack of pollen the brood area, and ultimately colony size, will shrink. It’s not just the amount of pollen that matters, but the quality; some pollens are densely packed with what bees need, and some are not. In my area, the pollen from ‘pussy willows’ in March is incredibly important for the rapid growth of colonies in Spring.

Honey bees collect pollen, nectar, and water to feed the colony and provide the nutrients for healthy growth and vigour. When you look at larvae on the combs, you want to see young larvae immersed in floods of milky ‘jelly’ covering the base of the cells. If pollen is in short supply, or is deficient in any of the essential amino acids, there will be less and less jelly. Eventually, the queen stops laying, and the workers eat the larvae, which is not what beekeepers are trying to achieve. If you detect that pollen is running low, it could be time to add supplements.

Pollen Supplements

Later on in 2018 I spent some time with Randy Oliver near Grass Valley, Northern California, who happened to be running a field trial at the time on pollen substitutes. In his area there are frequently times when naturally available pollen is very limited, due to the hot and dry conditions, so pollen subs are a big deal over there. He has done a lot of work since then, looking into the ratios of amino acids and so on. Work by deGroot in 1953 showed that there are ten ‘essential amino acids’ for honey bees. Depending upon your location, you may find that not all of these are available in high amounts. For example, Somerville said that isoleucine was the main limiting amino acid in honey bee-collected pollen in Australia.

As luck would have it, here in the UK, for much of the year, pollen is usually in plentiful supply. Last year, after an insanely hot period in July, I did find that larvae were not well provisioned with jelly. This was frustrating as I was hoping to graft larvae from a particular colony but couldn’t. Well, I didn’t want to, as those larvae would not have been in the best of condition. I suppose the problem could have been a shortage of water, but I doubt it because the farmer has a water feature which is often visited by my bees. Somewhere in Fat Bees Skinny Bees, it’s mentioned that a lack of incoming nectar can reduce the urge to collect pollen. Sometimes feeding some syrup can kick-start the pollen gathering.

All Through The Season

Generally speaking, I don’t think my bees need supplements in my area. I have added amino acids to syrup on cell builders and that went very well. The thing that is likely to cause pollen shortages for me is bad weather. It’s not that the pollen is not there, but that the bees can’t get out to forage for it. The hazel catkins that I have seen this year have no bees on them, which is hardly surprising as it is January and 8 degrees Celsius. If we were to have a bad spring, with weeks of cold and rain, then the bees could miss out on the banquet of willow pollen on which they fuel their growth. At that point, I would certainly throw on some pollen supplements.

The main sources of pollen for my bees (as far as I can tell) are:

February: Hazel/Alder

March: Willow, Blackthorn, Plum

April: Cherry, Apple, OSR, Dandelion

May: Hawthorn, Sycamore, Horse Chestnut

June: Field bean, Lime, Bramble

July: White clover, Borage, Rosebay Willowherb

August: Himalayan balsam

September: Ivy

However, hazel/alder are too early, OSR is usually not nearby, I wish I could find some field beans (I will have to ask around), and borage is just a few tiny clumps here and there. All in all, there is plenty for the bees to consume throughout the season. I just have to be ready for when the weather mucks it up.

Don’t underestimate the power of good nutrition for your bees. That doesn’t mean throw all sorts of weird and wonderful, and probably expensive, products at them all through the year. It does mean be ready to step in with syrup or pollen supplements when conditions force your hand.