If Bees Disappear, Will We Starve?

Is it true that if bees die, we die?

Do we really need bees to grow all our food?

With the publicity surrounding bee decline, these are common questions.  People are asking themselves how much we need to be concerned.  I sometimes get asked these questions, among others, such as:

  • "Can other insects step in to perform the function of bees, in pollinating our food crops as well as flowers and trees?"  
  • "Do we really need bees to grow food, and can other insects do the job of bees?"

Another question tends to focus on honey bees: "If honey bees (specifically) disappear, will humans starve, and do honey bees do all the pollinating?"

Let’s tackle these questions.

Firstly, studies have shown, that in terms of crop pollination, wild pollinators can do the job of honey bees at least for some crops.

For example, a study (published Feb 2013) by Garibaldi et al states that wild pollinators enhance fruit set of crops, regardless of honey bee abundance, and that pollination by managed honey bees supplemented, rather than substituted, pollination by wild insects.  (You can find the study here - copy and paste the web address into a new window: http://www.sciencemag.org/content/339/6127/1608)

Thus in an agricultural system where insect pollinator abundance is promoted and can thrive, a variety of bees and pollinating insects will quite naturally pollinate crops, and will do the bulk of the pollinating.

However, without a doubt, honey bees are very important for certain crops, such as almonds, and their importance extends even beyond pollination services!

But, it does seem that if honey bees disappeared off the planet tomorrow (not that we would want them to!), then in theory, other pollinators could step in to replace honey bees to pollinate at least some - and probably quite a lot of our food crops.


Such a scenario requires that wild pollinators are available and can thrive on farmland - the land where pollination is required.

Domesticated honey bees kept by keepers, are moved around from one area to another, and a beekeeper can step in to take action and assist the colony if necessary.

But this is obviously not the case for wild bees.  It doesn't take a rocket scientist to conclude that in order to encourage wild bees, environmental conditions have to be right, which means:

  • appropriate foraging opportunities
  • appropriate nest site availability (variable depending on species)
  • not being poisoned by insecticides!

Indeed, formerly wild bee species are increasingly being reared commercially and are being sold for pollination services to farmers who otherwise could not guarantee the presence of these pollinators on their land.

So can we relax?

No, because to continue to rely on commercial rearing of particular pollinators for food crops, instead of addressing the problems that are causing decline, is risky for food security, and it is taking a sticking plaster approach to solving our problems.

We might be able to breed a few bee species, but we cannot breed one of every bee, butterfly, moth and pollinating beetle, not to mention a myriad other beneficial invertebrates.

It also ignores the importance of diversity and species abundance in the wider landscape and this inter-related ecosystem.  Simply breeding a few more bee species for commercial pollination merely solves a potential glitch in preserving intense farming practices.

If the environment is bad for honey bees, it's probably bad for wild bees and other insect pollinators too.

Unfortunately, honey bees are not the only bee species – or even pollinator or invertebrate species having problems.  Wild species and invertebrates have been declining. 

The focus on honey bees in the media may create a distorted impression of the real scenario.  However, the reason honey bees have received so much focus, is because they are more closely observed by humans than any other invertebrate species. 

For example, commercial beekeepers such as Tom Theobald providing pollination services to agriculture, as well as hobby beekeepers, have collectively raised alarm for quite some years, and especially in connection with neonicotinoid pesticides.   

Nevertheless, the problems faced by honey bees and reported by beekeepers, really should raise alarm generally, because it should lead us to ask questions:

  • if something is affecting honey bees, is it also affecting other species?
  • are environmental factors responsible (in the cas of bee decline, we know there are multiple causes: habitat loss, poisoning by pesticides, diseases)
  • what monitoring do we need to put in place, and what actions do we need to take?  (Indeed, I think more focus and resource is needed on monitoring a larger variety of insect species generally).

Decline In Pollinators And Corresponding Decline In Plant Species

What some research tells us is that with species decline, there occurs a corresponding degradation or decline in vegetation/the wider eco-system.

For example:

  • Data gathered 120 years ago (1888 and 1891) in a temperate forest in Illinois USA, was compared with data gathered between 1971 and 1972, and data gathered again between 2009 and 2010.

    They found that half of the wild bee species had disappeared over the time frame, and that the quantity and quality of pollination services had declined through time.

    They concluded that although the environment had adapted, the eco-system had been compromised, and that further degradation would have serious impacts. 

    REF: Burkle et al: Plant-Pollinator Interactions over 120 Years: Loss of Species, Co-Occurrence, and Function; publ. Feb 2013. (Ref: http://www.sciencemag.org/content/339/6127/1611)

  • In Britain and the Netherlands,  Biesmeijer et al (2006) compiled nearly 1 million records of native wild bee and hoverfly species from data gathered before and after 1980, using national databases.

    They found that the number of bee species declined significantly in over half of the areas analysed.


    -  a significant decline in species numbers was recorded in 52% of the 10 x 10km geographical squares they analysed in the UK, whilst bee diversity increased in only 10% of squares; and overall, there were 29% fewer bee and hoverfly species occurring in Britain after 1980.  


    -  a significant decline in species numbers was recorded in 67% of Dutch geographical squares, whilst bee diversity increased in only 4% of squares.
  • In conjunction with these findings, Biesmeijer et al. also found that the number of plant species relying on insect-pollination, had also declined in the same period (species pollinated by wind or water were increasing). 
  • Ref: Biesmeijer, J.C., et al. 2006. Parallel declines in pollinators and insect-pollinated plants in Britain and the Netherlands. Science 313: 351-354


Generally, there may be some overlap in pollination of some plants by some species (i.e. multiple pollinators may provide a potential pollination service for particular plants). 

However, this is not always the case.

What the evidence suggests is that loss of species does not necessarily mean that this will definitely be compensated for by other species, and that unfortunately, biodiversity foots the bill.

Indeed, we know that certain plant species can only be pollinated by a very limited number of insect species. 

For example, some species of orchid and fig are only pollinated by particular wasp species.  

Evidence Of Insect Declines

Many reports can be found on the internet, however, here are a few examples of resources detailing decline of bees and other insects:

  • Cameron et al. (2011) reported a 96% decline in abundance of bumblebees over the last 30 years in the USA. Cameron, S.A., et al. 2011. Patterns of widespread decline in North American bumble bees. (Ref: Proceedings of the National Academy of Sciences of the United States of America 108: 662-667).
  • According to Butterfly Conservation, Britain has witnessed significant decline (30% over the last 10 years) in mean abundance of 40 butterfly species assessed. (Ref: Butterfly Conservation Brochure 2007).
  • According to Buglife, Europe’s largest Invertebrate conservation organisation:- almost a third of all bees and wasps are under threat
    - over 70% of butterflies are declining significantly
    - at least 15% (about 4,500 species) of all UK invertebrates are under threat.

    - species such as the Short-haired bumblebee and the Essex emerald moth have become extinct in the last 15 years.


  • habitat loss
  • pesticide poisoning
  • diseases and mite
  • introduction of diseases via commercially reared bees (according to Xerces in the USA, commercially reared bumblebees may be a threat to wild bumblebees: B. affinis, B. occidentalis, B. terricola, and B. frankliniYou can read more about it here).

So if bees die, will we starve?

We don't know what the effects would be!

It is generally proposed that bees are responsible for a third of the food we eat, but it's not always easy to work out how this figure was calculated.

Thus, there are many questions:

  • is this simply food directly eaten by humans (e.g. fruits, almonds)?
  • are animal food crops taken into account? - for example, bees pollinate alfalfa, which is eaten by cattle.  Is this included in the 'one third' figure? 
  • are we really only talking about bees, and what about the role of wild pollinators (such as flies, beetles, butterflies, moths - and in some countries, even birds and bats).
  • do the figures take into account the importance of seed setting to ensure future crops, and where bees are responsible for the setting of seed? 
  • do the figures even include the honey industry?
  • how is the figure calculated (does the one third refer to volume amount, or cash value?).


  • We cannot really know the full impact of bee declines and deaths.  We can only develop theories, but we have surely learned enough to understand that declines in some species will ultimately result in the loss of other species - and this includes plants. 

  • Some crops are pollinated by wind.   Arguably, these would not be affected by bee decline.  However, if something in the enviornment is affecting bees, it may be affecting other creatures which are important for wind pollinated crops.  For example, if pesticides are poisoning bees, they may also be killing beneficial earth worms and soil organisms.  This may impact crops which don't require bees for pollination.

  • What about the knock on effect for other species, also dependent on bees in some way? Eventually there may be consequencies for humans, if only indirectly - but at this moment, we cannot be sure what all the consequences would be!  Our knowledge of the earth and the role of each species is actually very limited.   For example, it's only fairly recently that we discovered how important sea plankton is to humans!

  • Then again, in some parts of the world, some crops are already being pollinated by hand.  This is the case in parts of China's Sichuan province - where pears are grown, and where bees cannot thrive in the environment due to pesticide poisoning.  What if this were to be necessary on a larger scale!
Above: workers climb pear trees in Sichuan Province, China, in order to pollinate the trees by hand.

Wouldn't it be better to do all we can to reverse bee declines?  Here are 10 things you can do - and why not ask your council to help out too!

3 Ways wasps benefit people and the planet