Are the populations of bees and butterflies declining?


By Chandre Dharmawardana, Canada

There are always intermittent reports and circulation of petitions about the loss of bee populations, butterfly populations, fire-fly population etc; and evident environmental damage. These reports are never accompanied by entomological surveys of insect populations and other relevant data. The groups circulating the petitions never fail to ask for donations to save the world, usually by claiming to take big agrochemical companies to court, or taking steps to ban some agrochemical product alleged to be "highly dangerous".

Why should we worry about populations of bees and butterflies? They are the agents who pollinate our plants and ensure our food supply, besides doing many other good things.

Instead of giving data, these petitions will claim that the reader in his/her childhood days saw many butterflies, bees and fireflies, while today this is not the case. In Sri Lanka, they would allude to the migration of butterflies to "pay homage to Adam's peak or Samanala gala". Of course, many people who had a rural childhood live today in crowded urban jungles enmeshed with roads choked with traffic full of half-burnt fossil fuel emissions. Why would they expect to see butterflies or bees in such concrete jungles?

Have the bee populations actually decreased drastically?

According to a comprehensive review article by Prof. David Goulson (Fellow of the Royal Society and Professor at the University of Cambridge), and his colleagues, the honey bee populations in the world have INCREASED by 40% over the last decade. Please see the research article in the famous journal "Science", published by the American Association for the Advancement of Science: Science. 2015 Mar 27; 347(6229):1255957.

Although there has been an increase in agrochemical use, they do not seem to have a negative impact on honey-bee populations. While modern agrochemicals do not seem to have a negative effect, chemicals used to control dengue and other mosquitoes will certainly have an effect. It should be noted that the estimates of bee populations given by Goulson and colleagues are not based on nostalgic tales, but actual counts taken over many locations in the industrial world, over decades. Similar data need to be collected for Sri Lankan bee and butterfly populations, using citizen science groups, just as amateur enthusiasts who are ``bird watchers'' keep track of bird populations.

What has decreased all over the world is the population of WILD BEES. Some species of butterflies (e.g., Monarch butterfly) have also decreased due to the removal of specific flowering plants (Milkweed or "Varaa" in Sinhala,) due to urbanization and cutting down of forest.

1. This loss of wild bees is mostly due to LOSS of HABITAT due to people felling forests and building houses and roads. This reduces the amount of forest and bush available for wild bees, butterflies and indeed all flora and fauna. Even the elephant population in the Sinharaja has now been reduced to just two elephants - this is NOT due to glyphosate or pesticide use.

Haphazard urbanization should be stopped, and the existing forests must be preserved and forest cover MUST BE increased. Roads passing through forest reserves must NOT be build. Much of waste farmland should be returned to forest instead of dredging and building houses. But even the Wilpattu has been razed for building human habitations, ostensibly for "war-displaced Muslims".

2. Furthermore, human populations and urbanization help the growth of parasites which harm bees. The noxious fumes from motor vehicles, diesel engines, farm tractors, electronic and mining industries, coal-power plants, etc., burning of garbage, increased particulate dust are vital factors producing extreme environmental stress on bees and butterflies.

3. The excessive use of pesticides has also been mentioned, but the chief entomologist of the primary agricultural research institute in Britain (Rothamstead Research Inst.) has stated that there is no clear evidence that neo-necotinoids are a cause of wild-bee decline. Similar views have been expressed by many leading entomologists, while the opposite opinion has also been expressed by some individuals.

Glyphosate acts on green plants, and have no direct impact on fauna, insects and other zoo-species. In fact it is known to encourage the growth of soil microbes, earthworms, etc. Its impact is only on plant-species as the mode of action of glyphosate is to interfere with photosynthesis (i.e., living species having chlorophyll). Bees don't have chlorophyll and are unaffected by glyphosate.

Such herbicides are used to control weeds and this may lead to a reduction of some weeds useful to wild bees. But usual planted species (e.g., tomatoes, tea bushes) also provide flowers that are valuable to wild bees and so there is a compensating effect as long as flowering plants are used in farmlands which often tend to be mono-cultures (e.g., vast extensions of corn fields). Plantations which are mono-cultures are not ecologically balanced. Most knowledgeable farmers inter-space their crops with strips of flowering plants, herbs, legumes, etc., to help desirable insect populations and soil microbes.

Many of the so-called environmental groups are unwitting instruments in the hands of certain neo-liberal advocacy groups. They are targeting our food supply because of their hidden agenda to push forward "organic food" and reduce the world food supply and diminish the world population by starving out the third world. Similar attacks on the "green revolutions" are common, and repeated even by "green activists" of the developing world who simple repeat what they read on the internet.

They have ignored the items 1 and 2 which threaten wild-bee populations. Instead, they have concentrated ONLY on herbicides like glyphosate that have NO direct effect on bees, while the indirect effects are utterly negligible compared to items 1 and 2. They nearly succeeded in banning glyphosate in Sri Lanka even though 192 of the 195 countries in the world fully approve of the use of glyphosate in agriculture.

So banning glyphosate (or neo-nicotinides used for eliminating mealy bugs in potatoes and such crops) will NOT eliminate the primary cause of the decline of wild bees, butterflies and other useful WILD insects. Of course, reducing agrochemical usage without upsetting food production is a desirable objective. Moving away from potato and meat diets, diary production, moving to rice diets and vegetarianism, together with a sharp reduction in the use of fossil-fuel based motor vehicules, stopping sprawling urbanization, and stabilization of the rising human population are essential to saving the threatened environment as well as its threatened insect populations.

The reason why rice diets are preferred to potato diets is explained in my most recent research article on the implications of the use of fertilizers on the health of water, soil, and the food supply. Please see:

Environmental Geochemistry and Health: June 2018, Fertilizer usage and cadmium in soils, crops and food,

Finally, we should note a commonly held myth that "nature's fine balance has been upset by man''.

Nature has never been in "balance". Indeed the fossil records, the lists of extinctions of species, etc., show that it is a highly driven system way out of equilibrium. The intense energy that falls on it from the sun drives geological and evolutionary change. Man himself is a part of this great dissipative process and he too will become extinct in time to come. Nevertheless, we as humans have evolved to have "intelligence", and hence look for slowing down the inexorable process as much as possible!

However, a few idiots and crooks at the helm are enough to upset all the good work of well-meaning individuals.


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