Economic Valuation Of Ecosystem Services - Insect Diversity

An ecological apocalypse

19.1 July 2019

A friend asked me recently – “Where have all the insects gone?” I must admit that I had not noticed their slow disappearance over recent decades. But her enquiry provoked long unconsidered memories. As a young man in the 1970’s on undertaking any long drive I carried a bottle of water and a rag in my car to clean the windscreen every few hours. Some four decades ago it would have been covered in splattered insects. Today I don’t carry any such equipment – I rarely need to clean the windscreen.

“Insects are by far the most species-rich taxonomic group on Earth.
To date 950,000 insect species have been described and many millions of others await discovery.”³

Insects first appeared on the land nearly 400 million years ago. By the Carboniferous period, 100 million years later, they had evolved into the many diverse species we see today.⁴

There may be 30 million or perhaps 50 million or more species of insects on Earth.⁵ Scientists do not know the true number. It is strange to realise that only in recent decades has humanity taken any account of this keystone genus and made any assessment of their populations.

Insects are the most species rich group on Earth and play numerous crucial roles within the Earth’s ecosystems.⁶

It is only recently that we have discovered the shocking decline in their abundance⁷ – discovered that their very existence is threatened!

“Loss of insect diversity and abundance is expected to provoke cascading effects on food webs and to jeopardize ecosystem services.”⁸

We all too often regard insects as insignificant creepy crawlies – too small to be considered important. But insects constitute the world’s most abundant animal group⁹ and perform three key functions in the Earth’s ecosystems. They act as eliminators, facilitators and providers.¹⁰Insects act as eliminators in ecosystems by removing waste products and dead organisms. Herbivores consume and recycle plant material and carnivores eat other animals. Insects also act as facilitators by performing pollination, seed dispersal and microhabitat development.¹⁰ For example 80% of wild plants are estimated to depend on insects for pollination.¹¹ Insects are providers in ecosystems by acting as food for a range of other animals and some plants.¹⁰

They form the base of many food chains and without them many other species would not survive, including many birds, fish, reptiles and mammals.¹²

The cumulative biomass of insects is likely to represent a small fraction of the total biomass in most systems – estimated at 1.0% to 5.2%. However, insects have large effects and should be recognised as important drivers of ecosystem processes.¹³ Thus, the presence of insects is important to the distribution, abundance and diversity of many plants and animals¹⁰ and are fundamental to all ecosystems – they are life-sustaining.⁴

If the insect population is severely reduced productivity drops and nutrient cycles are clogged. As the best adapted pollinators such as bees become extinct less competent species take over. The result is fewer seeds are formed and fewer seedlings sprout. In consequence herbivores and the animals that prey upon them decline.⁴

“The actual structural and functional collapse of the natural systems which have supported life on Earth for the last 400 million years.”¹²

The extinction of say 50% or more insect species would mean that our generation will participate in an extinction process involving 15 to 25 million species. The actual number is not important – “it is a massive destruction of the biological richness of Earth.”⁵ Thus the result of a massive loss of Earth’s insects or “insectageddon”¹ would be a cascading catastrophic failure of the planet’s ecosystems- and the really scary fact is that without urgent action to save them we may well experience this in our lifetime.¹²

“Our generation is presiding over an ecological apocalypse.”²

Such population declines imply not only less abundance but also represent the first step towards extinction.¹⁴ Only now are global declines in insects attracting wide interest from scientists. The significant loss of insects across Europe is now a proven fact and should give rise to serious concern among politicians and public alike.⁸

Certainly, scientists are now starting to pay attention to the issue but as a species humanity needs to “rise above profit and greed”⁵ and make fundamental changes to how we treat Nature. Only then maybe – just maybe – this crisis to the biodiversity of Earth can be avoided.

The grim facts

19.2 July 2019

Only now are global declines in insects attracting interest from scientists. This is especially since the publication of a research paper in October 2017 which confirmed the results of a survey of insect populations in Germany. The team used Malaise Traps to measure the total insect biomass of over 63 nature reserves across the country. Their conclusions are shocking!²

“Our analysis estimates a seasonal decline of 76%…in flying insect biomass over the 27 years of study.”²

And even worse the study found a more severe decline of 82% in mid-summer. The researchers suggest this major decline in aerial insect biomass was probably not due to habitat loss and climate change – rather that the plausible explanations may be agricultural intensification including pesticide use, year-round tillage and the increased use of fertilisers.²

“Whatever the cause…for the decline, they have a far more devastating effect on total insect biomass than has been appreciated previously.”²

These results illustrate an ongoing and rapid decline populations of airborne insects and highlights a crisis in insect numbers that could have significant consequences.² Of more concern is the fact that such catastrophic declines occurred in nature reserves – areas that should provide refuge for insects. We can only speculate about conditions across the majority of the landscape which suffers under intense agricultural production and today supports virtually no insect life.³

“There has been some kind of horrific decline…we appear to be making vast tracks of land inhospitable to most life forms…and are currently on course for ecological Armageddon.”
“If we lose the insects…then everything is going to collapse.”⁴

It’s alarming to realise that my anecdotal observations have been confirmed by the grim facts of a scientific study which has concluded that the flying insect community has been decimated over the last few decades.

Similar studies in North America and Europe confirm this shocking decline insect populations. For example a 36 year study in Puerto Rico reported a biomass loss of 98% for ground dwelling and 78% for canopy dwelling arthropods.⁵ In Europe grassland butterflies populations are estimated to have declined by 50% between 1990 and 2011.⁶ Similarly studies across the United Kingdom (UK) of Butterflies, Large Moths and Beetles over recent decades tell a similar story of massive decline in populations.³

“76% (44 out of 58 species studied) of the UK’s resident and regular migrant Butterfly species declined in either population or occurrence (or both) over the past four decades.”⁷

“Across Britain, the total abundance of Larger Moths declined significantly by 28% during the 40 years period from 1968 to 2007.”⁸

Sixty-two species of moths became extinct in Britain during the twentieth century and several more are now thought to have been lost including the Orange Upperwing, Boardered Gothic and Brighton Wainscote moths. The V-Moth (Macaria wauaria) recorded a 99% fall in its numbers between 1968 and 2007 and is now also threatened with extinction.⁸

But it’s not just Butterflies and Moths that are suffering. Studies of 68 species of Beetle across the UK over 15 years found that 75% had declined in numbers. For example, many of Britain’s native species of Ladybirds are suffering serious declines. A survey of the Two-Spotted Ladybird in 2012 found that populations had slumped by 44%. Also, populations of both wild and domesticated bees have witnessed a steep decline.³

“Urgent need to uncover the causes of this decline…and to understand the ramifications of the decline for ecosystems.”²

Species such as Butterflies and Larger Moths are relatively easy to identify and are well studied. They can act as indicators of the wider state of insects populations and as a sensitive gauge of the impacts of habitat change, pesticide use or climate change on wider biodiversity within an ecosystem.⁷ Their overall decline is indicative of the rapid loss of insect biodiversity in Britain, and other countries, which may have substantial impacts on other wildlife and effect the delivery of some ecosystem services.⁸

“The decline and extinction of species is occurring at a rapid rate.”⁸

Studies over 40 years of insect population trends and other results provide grim evidence of steep declines. These show few signs of recovery despite the best efforts of conservation organisations and large government expenditure.⁷ Which is of great concern as the substantial decline of Britain’s insects is one of the clearest signals yet of potentially catastrophic biodiversity loss caused by human impacts on the environment.

Destruction of habitat

19.3 August 2019

“Britain’s insects…are dissapearing.”²

Over recent decades many factors have resulted in the decline of insect diversity and abundance across Britain. In order of importance the main causes appear to be: habitat loss, pollution – mainly by synthetic pesticides and fertilisers – biological factors such as pathogens and introduced species and Climate Change.³

Habitat change is an immediate consequence of human activity. Increasing amounts of the natural landscape are being transformed for food production and to provide sites for buildings and transport infrastructure.⁴

“The intensive management of agricultural land had by far the largest negative impact on nature across all habitats and species.”⁵

Since the 1950’s a general intensification of agricultural management has taken place as practices shifted from a traditional, low-impact farming style to intensive, industrial-scale production. This process included the planting of genetically uniform monocultures, the repeated use of pesticides and synthetic fertilizers,⁹ the abandonment of mixed farming systems, the intensification of grazing regimes⁶ and widespread loss of hedgerows, boundary trees, and botanically-rich field margins.⁷ These major changes to agriculture management and techniques were all instigated by policies decided by both the UK and European governments.⁶ All have had major negative impacts on insect populations.

“Habitat management for insect conservation and biodiversity should be a primary goal.”⁸

Communities and individuals could help reverse the trend through planting flowers and grasses to roadsides, rail embankments, municipal parks and private gardens to provide essential resources and habitat for insects.⁹ However while this may play an important role it is essential that improvements to both rural and urban environments to encourage biodiversity also be undertaken at a national level. Conservation actions that reverse the decline of threatened species will require dramatic and large-scale changes to Government Policy. This will involve changes to funding for agriculture and woodland management to the benefit of species and habitat conservation.

It will also require a total change in methods of agricultural production¹⁸ and most importantly a drastic reduction – if not total elimination- of the use of agro-chemicals.

“Thousands of protected areas in the UK represent sanctuary for biodiversity.”⁹

Legislation will also be required and to reduce the pressure on the natural landscape caused by intensive agriculture and house building by maintaining, restoring and creating high-quality resilient habitats through landscape-scale projects.⁹ Currently about 2% of the UK is designated as Nature Reserves and some 10% as Special Protected areas.⁶ Based on recent studies it seems obvious that current conservation efforts are proving insufficient.

Numerous genetically diverse populations are necessary to ensure persistence of a species.¹⁰ This can only be achieved through the creation of more nature reserves. Such reserves need to be very large and selected to protect examples of the widest possible range of native ecosystems and habitats.¹⁰

Currently the remaining insect populations occupy islands of suitable semi-natural habitat amongst a sea of intensively managed and hence unsuitable land. As the landscape becomes more fragmented the likelihood of extinction increases. Thus, legislation is required to protect all such existing natural habitats but also extend them to provide connectivity.⁹

“Conserve biodiversity by establishing natural area preserves.”¹¹

Recent experiments have shown that there is an alternative to the highly managed conservation projects that consume a great deal of time and money – that is by simply returning large areas of land to nature. Examples in Holland and Britain have demonstrated that a landscape free for all human activity or intervention allows nature takes its course and quickly re-establish balanced and thriving ecosystems. Immense tracts of marginal land across the UK should be designated as such wild reserves.

“Climate Change is…predicted to change distribution and therefore diversity patterns of insects.”¹²

Insect species richness and composition are known to be strongly affected by environmental factors such as temperature and moisture. Climate Change is causing numerous changes in the geographical range, abundance, phenology, ecology and interactions of species and is widely perceived as a significant and increasing risk.¹³ Most species have declined in a reaction to Climate Change.¹¹. It will require a concerted International effort to achieve the required reductions to global greenhouse gas emissions agreed in the 2015 Paris Climate Accord.

The massive and wide-ranging decline of insect populations experienced over recent decades requires a dramatic change in the approach to conservation.⁹ Urgent action is required to reverse this trend and begin to manage habitats for the benefit of insects – and Nature as a whole.⁶

Lethal toxins

19.4 August 2019

“Pollution is the second major driver of insect declines.”²

Generally, insects are killed by lethal and sub-acute toxins in the soil, air and water resulting from things like industrial waste.³ One of the sources of such environmental pollution includes synthetic fertilisers and pesticides used in agriculture. Modern intensive agriculture implies the systematic and widespread use of pesticides for controlling crop pests (insecticides), competing weeds (herbicides) and fungal infections (fungicides).²

“In terms of toxicity – insecticides are by far the most toxic to all insects.”²

In addition to the species targeted by such treatments intentionally applied chemicals such as insecticides can cause the death of an array of other species.³

Insecticides reduce the diversity and abundance of plant foraging and ground dwelling insects. For example, they reduce populations of ladybirds and butterflies and inflict multiple lethal and sub-lethal effects on bees.²

Despite such devastating effects there has been an increase in applications of fertilizers, herbicides and pesticides across the UK.⁴ In 2018 the total utilised agricultural area (UAA) covered an area of almost 17.5 million hectares of the UK – some 72% of the land area.⁵ Pesticide Usage Surveys (PUS) for 2016 confirmed that some 73.17 million hectares were sprayed with insecticides or similar products.⁶ This is obviously far more than the total land area under cultivation. The reason is that each crop is treated with pesticides multiple times.⁶

For example, in 2015 on average each hectare of farmland was treated 4.2 times with pesticides in the growing season.⁷ Not only are farmers repeatedly treating crops the overall areas of land being treated has also increased. Between 1990 and 2016 the area of land treated with all pesticides rose by 63%, the area treated with fungicides by 69% and herbicides by 60%.⁷

“The new classes of insecticides introduced in the past 20 years – eg. neonictinoids and fipronil have been particularly damaging because they are used routinely and sterilise the soil…killing everything.”⁹

The broad adoption of new types of insecticides including neonicotinoids and fipronil has been especially lethal.¹⁰ Modern neonicotinoids are 10,000 times more potent that DDT, history’s most notorious insecticide, which was banned in 2001 due to its impact on the environment.⁷

Insecticides are “any substance that is used to kill insects”¹¹ – simply they do what is says on the label – they indiscriminately kill insects of all species over extensive areas.¹² Why should anyone be surprised that the constant and repeated application of such lethal toxins across vast tracts of the landscape should do anything but decimate insect populations?

“Many factors have resulted in the decline of the UK’s wildlife over recent decades…but policy driven agricultural change was by far the most significant.”¹³

There is compelling evidence that agricultural intensification and the extensive use of pesticides is a primary factor for the decline of insect populations.¹⁴Major changes of current agricultural practices, in particular a serious reduction in pesticide usage and its substitution with more sustainable ecological based practices, are urgently needed to slow or reverse current declining insect populations and allow their recovery.¹⁴ The government should provide more support to farmers using minimal or no pesticides.⁷

“Industrial-scale, intensive agriculture is…killing the ecosystems.
The world must change the way it produces food.”¹⁰

A global treaty is required to regulate pesticides worldwide, commencing with very strict controls on production and use and leading eventually to a total ban. Global policy changes supported by financial incentives are required to encourage a move away from intensive farming¹ to sustainable ecologically based practices.⁹

“The conclusion is clear:
Unless we change our ways of producing food, insects as a whole will go down the path of extinction in a few decades.”²

The state of insect biodiversity across the Earth is now critical. Almost half of the species are rapidly declining and a third are threatened with extinction.¹⁵ The staggering worldwide decline of insects is a warning of wider ecosystem collapse. The primary reasons for such declines are the loss of habitat due to intensive agriculture, deforestation and urbanisation and poisoning by pesticides and synthetic fertilisers.⁹

“It is imperative that current pesticide usage – mainly insecticides and fungicides, are reduced to a minimum.”²

Or better still stopped completely! The situation is dire – insects – all life on Earth – urgently needs radical new policies and investment to create a landscape that supports and encourages Nature rather than kills it.¹³

Preserving insect abundance

19.5 September 2019

“The most likely cause of this insectageddon is that the land…has become hostile to them. The volume of pesticides and the destruction of habitat have turned farmland into a wild life desert.”¹

The decline of insect populations across Britain appears to have started at the beginning of the 20th century, the trend accelerated in the 1960’s but has only reached alarming proportions over the last two decades. Butterflies and moths are amongst the worst affected. Declines have also been witnessed in beetle populations and most infamously in bees.³ Within temperate regions the UK seems to have the largest documented declines with 60% of species threatened. Similar dramatic losses seem to be have been happening worldwide.

For instance, North America has 51% and Europe has 44% of insect species threatened.⁴

“The shocking collapse of insect populations hints at a global ecological meltdown.”¹

Such significant declines of insects is important not just for their conservation but also to global biodiversity and the future health of Earth’s ecosystems.⁵ It is shocking to realise that among the major issues that dominate our daily media this crucial issue – one that could potentially threaten the existence of much of life on Earth – receives little or no coverage.¹ Such grim facts simply cannot be ignored but should prompt worldwide decisive action to avert a cascading collapse of the world’s ecosystems.⁴ Humanity needs to wake up to the seriousness of this crisis and undertake a total transformation of its current industrial and agricultural practices and save the insects from extinction.⁶

“Insects are critical to the survival of the rest of the living world.”¹

After decades of destruction Nature across the UK is now greatly diminished. We urgently need to recreate habitat, restore degraded areas and ban the wholesale use of pesticides. But even this may not be sufficient to turn the tide and prevent the decline and extinction of many insect species.⁷

“Preserving insect abundance and diversity should constitute a prime conservation priority.”²

Policy makers, environmentalists and we the public need to understand the vital role of insects in ecosystems and seek to preserve and enhance insect species diversity and abundance.⁸ It is imperative that governments – that we – stop this mass slaughter of insect life. It’s time that our priorities are fundamentally changed to make life on Earth more important than “returns to shareholders”¹ Money will count for nothing when we have lost the living systems on which the survival of life on Earth depends.¹

“The world’s insects are hurtling down the path to extinction.”³

Insects are by far the most varied and abundant animals and are essential to the proper functioning of all ecosystems. More than 40% of insect species are in decline, and 33% are endangered.

Research suggest that if this trend continues insects “could vanish within a century.”³⁰ The latest research confirms that the sixth major extinction event is “profoundly impacting” all life forms on the Earth.³

“It is increasingly obvious that the planets ecology is breaking…and there is a need for an intense and global effort to halt and reverse these dreadful trends.”⁹

The grim fact that three quarters of the biomass of flying insects has disappeared in less than three decades should be a huge concern for us all.³Thousands of species are now formally recognised as threatened or endangered. The vast majority face extinction because of human action – we are busy destroying habitats and repeatedly spraying the landscape with toxins. We forget that insects are irreplaceable! Dramatic steps are required. A formidable effort is required to increase public awareness of this serious situation and of the need for urgent worldwide action. People everywhere need to understand the seriousness of the loss of insect diversity. If mankind does not take such dramatic action and soon.”…the extinction of much of the Earth’s biota cannot be avoided.”¹⁰

“The conservation of insect diversity and abundance is of crucial global importance”¹¹

Insects have played a fundamental role at the structural and functional base of many of the world’s ecosystems since their emergence at the end of the Devonian Period almost 400 million years ago. Unless immediate and positive action is taken to reverse current trends humanity – you and I – will be responsible for wiping out these whole taxa in a few short decades and the consequences of their loss for the planet’s ecosystems will be catastrophic.⁴

The Remembering

19.6 October 2019

“To forget – to fail to remember.”³

Memory, it seems, is a strange phenomenon. It slips away silently – subtly changing how we remember the world and thus how we perceive it. The world I see is transformed from the landscape my grandfather would have experienced.

“We are blind to the fact that in our grandparent’s day…there would have been species rich wild flower meadows…and coppice woods teeming with butterflies. And their summer nights were peppered with…moths and glow-worms.”⁴

Long gone are the tree lined lanes alive with the constant motion and sound of insects. My grandfather is dead – his memories lost. I can no longer measure my reality against his. I can no longer recall the great losses that have occurred since his day – I have forgotten.

“The ancient character of the land, the forests that covered it, and the animals that lived in them…have been forgotten.”⁵

In the 1970’s traditional mixed farms started to disappear and industrialised agri-business began to dominate the landscape. Hedgerows were ripped up⁵ and wildflower meadows ploughed.⁴ This process all but wiped out Britain’s natural habitat and much of its richness and complexity was lost.⁵

“Our memories have been wiped as clean as the land.”⁵

New giant fields were sprayed with copious amounts of herbicides and pesticides⁵ – resulting in the almost total disappearance of native flowers and insects from farmland.⁴ Intensive farming and changes in land use due to urbanisation have altered the national landscape beyond anything our grandparents would recognise.

“We live in a shadowland, a dim flattened relic of what there once was.”⁵
=”Memory…the ability of the mind to remember.”¹

“Memory is the process of encoding, storing and retrieving information. If the material is rehearsed long enough it…causes structural changes in the brain. These…are more or less permanent and are responsible for long-term memory.”⁶

Even if we do recognise such changes and ecological loss we usually only as go back as far back as our recollections of childhood. We are unaware that what we considered normal when we were children was in fact already a state of depletion.⁵ Thus with each generation the baseline drops and is considered to be the new normal. The result is a continuous lowering of standards and a generational acceptance of degraded ecosystems. This is called “Shifting Baseline Syndrome.”⁴ Thus slowly – generation by generation – the natural world slips away.

“Remember – to bring something from the past to mind.”³

“Remembering…the retrieval of implicit memories is automatic: when the appropriate stimulus occurs it …evokes the appropriate response. Recollection may be aided by contextual variables, including physical objects or…verbal stimuli.”⁶

But memory is elusive and slips away – even in our own lifetimes. My wife and I recently visited Malta. Touring in our small hire-car we became lost and found ourselves alone on a narrow country lane. I got out to try and assess where we were on the map and was suddenly overwhelmed by the sight and sounds of the landscape. Fields full of flowers, the air full of insects, and a constant deep buzzing of activity that assaulted the ears. I was shocked into a quiet contemplation of the abundance of life. I was shocked to realise that I had forgotten that it had once been like this in Britain.

“We forget that there was once more – much, much more.”⁴

Suddenly my memory was stimulated and I recalled a garden of my childhood humming with activity. Thousands of bees and other small insects buzzing around scented flowers and butterflies fluttering across the lawn.

“Remembrance – the act of remembering”³

We have forgotten that diversity is the foundation of the complex web of species interrelationships we call nature. The more species living in an ecosystem the higher its productivity and resilience and the greater the mass of living things it can sustain. But the inverse is also true – reduce biodiversity and biomass can decline exponentially.⁴

“Population crashes and extinctions are the signs of an ecosystem unravelling.”⁴

Today the United Kingdom is among the most nature-depleted countries in the world. Populations of many species have fallen dramatically. Insects have been particularly badly hit losing more than half of their populations since 1970.⁴ And we barely notice – we have forgotten.