Where Have All The Bees Gone?

Reasons why bees may have suddenly stopped visiting your garden.

I am thrilled that so many people are making their gardens as bee friendly as possible, and are taking an interest in the bee visitors to their gardens.

Quite a few people, however, are alarmed when it seems after a spell of regular visits by bees (especially bumble bees), suddenly the visits appear to stop, or decrease substantially. It seems the bees have gone, and people are worried that something is wrong. 

I find it's a fairly common query for people with smallish gardens (like mine).  I myself witness fluctuations in bee visits through the seasons, and the explanation is usually a natural one.

Where have the bees gone?  Reasons the bumble bees have stopped visiting your garden

For most people, these fluctuations in visits are conspicuous among bumble bees, because bumble bees are so recognisable, even when they are of a different species.  People are far less likely to be familiar with solitary species, which might also appear to be around for a few weeks, and then apparently ‘disappear’.

Anyway, in short, the reasons this occurs can often be explained as follows:

• Bumble bee species have varied life cycles, and emerge and decline at different times of the year
  
  Gardeners usually notice that one species of bumble bee – or sometimes two – becomes quite common in their garden, and they are very often seen foraging on a favoured flowering bush or patch of flowers. 
  By the time gardeners notice the bumble bees in any quantity, the colony (or colonies) of that species will be close to, or at its peak already, having produced lots of workers and possibly males.  This means that pretty soon, the colony will naturally come to an end, so that this particular species of bumble bee will no longer be seen in the person's garden. Only new queens will survive, and the new adult queens will find a place to overwinter, and then establish colonies again the following year.  You can read more about this on my page about the life cycle of bumble bees.
  
  In my small garden, I tend to see Bombus pratorum (Early bumble bee) and the Bombus terrestris (Buff-tailed bumble bee) first, and then they stop visiting, during which time, I see fewer bees.  Some time later, different species such as Bombus pascuorum (Common carder bumble bee) and Bombus hypnorum (Tree bumble bee) appear.

• Attractiveness of the plant or shrub depends on the amount of nectar and pollen it offers the bees
  
  Plants and shrubs vary in the amount of nectar and pollen they offer as they grow.  Quite simply, the bees may no longer be attracted to – e.g. my manuka shrub, despite being all over it previously, because it is no longer producing so much nectar.  So they forage elsewhere, and leave and leftover for the hoverflies.  I may or may not have plants in my garden that are at their most attractive to bees, just at that time.  Fluctuations in nectar production in plants, and resulting attractiveness to bees, has been studied.  For one such example, see my page about brambles.

• The bees are foraging somewhere else nearby
  
  Having a small garden, I am limited in the amount of flower I can provide,  and so linked to the point above, the bees may have found other shrubs and flowers nearby (not in my garden) at peak nectar output, and so they prefer to forage there. 
  
  I find this often occurs with smallish gardens.
  
  Sometimes at certain times of the year, even if I have very few bumble bees in my own garden, I can walk literally around the corner from my house, and find lots and lots of them foraging on comfrey, which has a very high nectar output (it’s so high in nectar, the tubular flowers are a major target for nectar robbing).  Similarly, wild brambles are a magnet for bees.  There are a lot around me, along with knapweed and hemp agrimony (wildflower favourites) and since I’m not interested in growing wild brambles, knapweed or hemp agrimony in my small patch of garden, I simply accept that at that point in time, the bees have found a better restaurant!

Advice?

In short, my advice would be not to worry too much.  Go for a walk around your immediate local area at different times of the day, and look about you.

Perhaps some-one else is like you – planting for bees, and just as your shrub or flower patch has reduced its nectar output, your neighbour has a tree in blossom that the bees cannot resist. 

Or maybe there are brambles nearby in a hedgerow, or some other fabulous plants. 

I find I see more bees when I focus on larger patches of particular bee-favourites, and also on plants to attract certain species.  I have deliberately included some plants for particular solitary species. 

For example, I see hairy footed flower bees for a few weeks early in the season on pulmonaria. 

I see wool carders on lamb’s ear, a flower I have deliberately included with this bee species in mind. 

Bumble bees absolutely love toadflax – Linaria purpurea, so I have plenty of it, and I also get lots of bees on my raspberries and purple loosestrife.  I have also included a hypericum shrub in my garden.

However, if you choose carefully, you may find you’ll attract different bees species back to your garden in a week or two.  

"I have a bee friendly garden, why aren't the bees visiting?"

If the above describes your scenario:

• Sometimes it takes a while, and it may be that you have to wait longer for bees to become established in your area.  It took several years before I finally managed to attract wool carders and hairy footed flower bees into my garden.
• There may be other shrubs and wildflowers nearby that the bees prefer to visit.
• It could be part of the worrying decline of bees in your area.

I would recommend that you persevere with your bee-friendly planting scheme, and if more people in your area do the same, this will help to establish populations of bees locally.