This is about that much publicized insect collapse in Puerto Rico, which the authors blamed on climate change. It turns out that they made a natural but rather big mistake, not correcting for the effects of Hurricane Hugo, which increased the numbers of birds and insects before one of their main data points. A more in depth analysis of the data finds no decrease, but rather, an increase of insects in the canopy with warming temperatures. It also finds an increase in numbers of frogs as temperatures increase.

I wonder how many of the papers who ran the original story, or who refer to it, will publish this correction? And how many will click and share the corrections if they do? More likely the original story continues to get repeated for years into the future. Anyway hope this helps a bit.

This is another article I'm writing to support people we help in the Facebook Doomsday Debunked group, that find us because they get scared, sometimes to the point of suicide, by such stories. Do share this with your friends if you find it useful, as they may be panicking too.

Here is how it was originally reported in the Guardian:

“Scientist Brad Lister returned to Puerto Rican rainforest after 35 years to find 98% of ground insects had vanished”

Insect collapse: ‘We are destroying our life support systems’

What confused the authors was, Hurricane Hugo which caused severe damage in Puerto Rica on 9th September 1989.

Insect numbers increase after hurricanes because of changes to the forest that create new opportunities for insects. The authors also didn’t take account of the way that this hurricane damage increased bird catches at the start of their sampling period. There was data available before Hurricane Hugo with lower numbers than the ones the authors used, but they did not include these.

This study re-examined the data they used as their source. It also looked at other more detailed data sets from 1993 and 1994 onwards.

For instance the original conclusion about the insectivorous Puerto Rican tody that it declined by 90% doesn’t match the mist-netting data or the point-count data (where someone records all the birds they see from a particular station over a period of time) which show the same values for 1980 and 2005.

Insects and other arthropods (spiders, millipedes, woodlice etc) in the canopy of the forest, far from declining, actually increase with increasing temperature. There are other things affect the numbers but there is a correlation with increasing temperature.

One species did decline, a kind of stick insect called Lamponius, but there wasn't any correlation with temperature in the population fluctuations over the years. It must be due to other effects (family Phasmatidae (stick insect) sub family Cladomorphinae )

The frogs, which also depend on insects, did not decrease, but rather have an increase of numbers with temperature, and again increase after hurricanes.

They conclude

"We found no evidence to support the conjecture that food webs are collapsing at LUQ [ Luquillo Long-Term Ecological Research project ] as a result of warming. The narrow focus on temperature-related aspects of climate change as the causative agent does not address the multiple disturbances (e.g., hurricanes and droughts) that affect the forest "

Populations are not declining and food webs are not collapsing at the Luquillo


How many of you have seen or shared that study that was on TV saying that we are headed for a world without insects in 40 years? This was a non systematic study that hit the headlines.

It was even on TV prime time news in the UK with a live interview with one of the authors.

This is the source for that story you often hear that we will lose all our insects in 40 years - which doesn’t make scientific sense. Even deserts have insects and our world is not headed for a desert, just some changes of habitat. Forest to savanna sometimes, some countries get drier, some warmer. However those of us who live in colder climes know about how insects almost vanish in winter, and butterflies hibernate or lay eggs to overwinter in temperate countries, and then as spring comes the flies, midges, caterpillars and then butterflies proliferates. Warmth encourages insects in colder parts of the world. It just doesn't make sense that a warmer world would be a world without insects. It's amazing the power of such slogans as "A world without insects in 40 years" to bypass our higher thinking, and lead to us saying and thinking things that we would never say if we just gave it some calm, collected, non hysterical thought. E.g. a world without greenfly? Is that really credible? Or a world without midges?

This is the infamous Highland midge at its most numerous, a tiny biting insect, each one is just a tiny pinprick but they affect you by the sheer numbers:

Click to watch on YouTube

Much though holiday makers and locals might wish for it in some ways, we are not headed for a world without the highland midge.

Or without beetles? It just doesn't make a lot of sense.

We can have decreasing insect diversity. Insect numbers can decrease as a result of drought. They usually increase with warmth especially in cooler climes. They also fluctuate for other reasons, for instance after hurricanes. They can increase hugely if the conditions are optimal for some particular insect, as with a locust swarm. With their short lives (usually) then the numbers often fluctuate greatly. But they can't just all vanish. If one insect decreases, then there's still all the soil, dung, decomposing wood, dead animals, dead plants, flowers, plants to eat, etc and soon another lot of insects will return.

Also, we can’t have a world without domestic honey bees either. That also makes no sense as it is a domesticated insect, which means we can increase numbers by just having more colonies. It’s like saying we are headed for a world without sheep. Only if we stop keeping sheep. This is especially striking in the Americas which don’t have a native honey bee - lots of bumble bees but no honey bee.

If you look at the numbers, the bees are increasing. From the FAO, counting beehives rather than bees, it increased from 66 million to 90 million in the world from 1994 to 2017:

And reasonably steady in the US


Did you know that the study that got all this attention and that is the basis of that climate change slogan had only one data point for the whole of China, for the domestic honeybee? It's like using sheep in a study on declines of mammals. Most of the map is blank, and the few studies they do include come from a literature search for "DECLIN*", which surely biased their results towards studies that found declines.

Those purple bars in Australia and China are for the domestic honeybee

There were some points in it of interest to academic readers who knew how to evaluate its limitations, but it should never have got so much publicity.

This is what the insect ecologist Manu Saunders had to say about it in a tweet:

The key take-home is the amount of white space on this map of available data showing local/regional declines. Most countries have no data. N.B. the single data points in Australia & China are both managed honey bees, not wild insects

— Dr Manu Saunders (@ManuSaunders) February 3, 2019

And for that matter neither of those populations are declining significantly either according to the FAO


More details here:

A week or so later the UN biodiversity in agriculture report came out. Their section on insects was systematic and thorough, based on sent in reports by experts in many countries reporting to the UN found a mixed picture. Some stable, some with mixed trends. Some countries reported increases of pollinators, such as Nepal, and also parts of Europe due to a policy encouraging flower rich field margins.

This is what the UN report says about wild insects and crops, it is much more to do with species diversity of insects They do a detailed analysis later on in the article, but this is a summary section near the start:

"While farmers in intensive systems often rent managed honey bees to pollinate their crops, the majority of farmers rely on bee populations maintained by local beekeepers and on wild pollinators. Moreover, it has been shown that pollination services are enhanced by the presence of wild insects even where honey bees are abundant. Both higher pollinator density and higher species diversity of pollinator visits to flowers have been found to be associated with higher crop yields. Species diversity among pollinators can also be important in buffering the supply of pollination services against the effects of fluctuations in the populations of individual species "


"Temperature changes associated with climate change can lead to shifts in flowering periods and mismatches between them and the active periods of pollinating insects, with negative consequences both for pollinator populations and for pollination services, although effects on pollination may be mitigated by the presence of a diverse range of pollinators ,Other seasonal abnormalities such as more frequent cold or windy days in spring can also disrupt pollination services, with pollinator diversity again potentially playing a buffering role. Shifting climatic zones are likely to require pollinator species to alter their geographical ranges. Some species may struggle to do this with sufficient speed"

Later on in the section 4.3.4 Associated biodiversity for pollination they talk about insects in detail. They talk about some individual reports.

They reported on a German study, which hit the news further back. That was a genuine decrease, but not due to global warming (which would be expected to increase numbers in temperate latitudes - you get more insects in warmer weather in colder countries). It was probably due to insecticides as well as changing farming practices with less field margins etc.

This was the original “Insect apocalypse” story which covered both the Costa Rico story and the German one:

This is my debunk of the German story

Short summary: This is a recent article about research from Germany that has lead to click bait alarmist stories. What it actually said was: in a number of nature reserves in Germany there are a quarter of the number of flying insects there used to be 27 years ago. It only tells us about what is happening in the local area around the reserve. This may be because of fewer hedgerows, or an increase in use of pesticides in that area. It is not because of climate change. A warmer world should have more insects in temperate latitudes.

The FAO report that since that study, Germany has started an Action Programme for Insect Protection which is here (you can use google translate to see it in English): Insektenschutz

The FAO talk about many countries who submitted reports tot the UN on measures they are taking to ensure biodiversity. This table summarizes their conclusions:

On insects for pollination then they were decreasing only on livestock grassland-based systems. Everywhere else, stable or mixed trends

They remark on the limited data for insects, but it is vastly better than that insects study that hit the news a week or so back.

They talk about many measures that countries are taking to help support pollination of their crops. For instance they cover Malaysia’s “stingless bees” project. These are a different species from honey bees that are adapted to tropical and subtropical species and are better able to pollinate their crops than traditional honey bees. And they do also produce honey. Stingless Bees - Facts, Information & Pictures

The government has promoted keeping of stingless bee colonies to help with pollination:

There are many more details there in the report about the many things countries worldwide are doing to encourage biodiversity. As well as UN recommendations of ways that they will be able to do more of this in the future.

If you read the report itself it is far from bleak and rather heartening to read about all these projects so many countries are involved in to protect biodiversity.

The report is reasonably optimistic about the future. Many countries implementing such practices for crops, but having problems getting them in place that need to be addressed. The report itself has identified many knowledge gaps and actions they need to take in the future.

This is their conclusion of the report:

Positive global developments include, on the one hand, growing awareness internationally of threats to the sustainability of food and agriculture, including those related to the loss of biodiversity, and on the other, upward trends in levels of adoption of various management practices that potentially contribute to the conservation and sustainable use of BFA. These developments need to be built upon by the global community. Knowledge gaps need to be filled, cooperation strengthened, including cross sectorally and internationally, and financial, human and technical resources mobilized. Effective legal and policy frameworks need to be put in place. The country-driven process of preparing The State of the World’s Biodiversity for Food and Agriculture has led to the identification of numerous gaps, needs and potential actions in the management of BFA. The next step is to take action. Over the years, the Commission on Genetic Resources for Food and Agriculture has overseen the development of global plans of action for genetic resources in the plant, animal and forest sectors. Implementation of these instruments needs to be stepped up. Consideration also needs to be given to how the international community can more effectively promote synergies in the management of all components of biodiversity, across these sectors and others, in the interests of a more sustainable food and agriculture.

The State of the World’s Biodiversity for Food and Agriculture 2019

We have many problems yes. We do need to preserve the biodiversity of insects. Not the numbers particularly, there are plenty of them, and their populations can grow quickly. But the biodiversity, for instance the more different species of pollinator the higher the yields of the crops that are insect pollinated.


Insects are of great value to us in many ways. Here is a summary of some of the insect services mentioned by professor Timothy Schowalter in his post to SciTech special reports:

  • Provisioning - honey, and also eaten directly, about 1,500 edible insect species consumed by 3,000 ethnic groups in 113 countries. They produce protein 300-fold more efficiently than cattle.
  • Medically, e.g. maggots for wounds, because they selectively feed on dead tissue.
  • Source of several pharmaceutical products
  • For silk, and cochineal
  • Pollination of 60–90% of plant species and critical to 35% of global crop production
  • Decomposition of animal and plant detritus, to release the nutrients to plants for the next generation
  • Removing and burying livestock dung (termites and dung beetles) to stop fouling pasture foliage and reduce nitrogen loss and habitat for blood-feeding flies, as well as increasing carbon and water storage in the soil
  • Preying on pest species (e.g. ladybirds eating greenfly)

Professor Timothy Schowalter argues that a better understanding of insect contributions to ecosystem services will improve our ability to sustain delivery of ecosystem services.

How do insects contribute to ecosystem services? | SciTech Europa


The dollar value of ecosystem services generally (including insects, but of all of nature) is very high. However this is a bit unrealistic, how they work this out.

One recent paper makes the value US$145 trillion in 1997, reduced today to US$125 trillion a year, because of damage to Earth’s ecosystems in the interim. That’s more than double the entire global economy. How can that be possible? You need to know how it is done, with an example:

Insect pollination is a classic ecosystem service. Insects pollinate our crops for free, and if they were to go extinct we would probably have to try and do it ourselves. We can therefore estimate the value of the bees’ work by calculating the cost of paying armies of people to wander from plant to plant with small pollen-covered paintbrushes. One estimate put this figure at US$217 billion a year.

Can you put a dollar value on nature?

And no - we can’t yet pollinate crops with robotic pollinators (maybe some day). We can make a start at it but the robotic drones have a very short flight time before they recharge, and it’s also a challenge for them to find the flowers - we are currently a long way away from a day when robobees will flit through our crops as pollinators.

Robotic bee could help pollinate crops as real bees decline

Autonomous Flying Microrobots (RoboBees)

There is another way to do the calculation - to work out the losses that would accrue if we didn’t have insects to do this for us. Using this method, the value of insect services for the US alone is many tens of billions.

The four insect services for which we provide value estimates—dung burial, pest control, pollination, and wildlife nutrition—were chosen not because of their importance but because of the availability of data and an algorithm for their estimation. We base our estimations of the value of each service on projections of losses that would accrue if insects were not functioning at their current level. We estimate the annual value of these ecological services provided in the United States to be at least $57 billion, an amount that justifies greater investment in the conservation of these services. Economic Value of Ecological Services Provided by Insects

We aren’t at any risk of a world without insects. But they are a very important part of our world, and we need to understand how they take part in our ecosystems and preserve their ecosystem services for ourselves and for the rest of the ecosystem too.


There are many initiatives worldwide to preserve biodiversity and ecosystem services. E.g. encouraging farmers to keep hedgerows, to keep important habitats in good condition etc.

Indeed, you can do your own bit to help with it. Plant insect friendly flowers in your garden. Put insect homes in your garden for them to live in. Make sure you have piles of old logs.

Ideas on attracting wildlife to your garden; expert advice from the RHS

You can also make “bug hotels” for your garden. it may look something like this:

Bug hotel (C) Alex McGregor

Or for a more natural look:

Bug Hotel Spiers

More tips here from AutumnWatch

There are so many gardens nowadays in the countryside and in cities - by making them a bit more bug friendly we can make a big difference.

And of course farmers can do similar things in their fields. It’s not something we need to watch helplessly.

If there are problems with insect populations there are many simple measures we and farmers can do to fix it.

See also my

This article originated on my Doomsday Debunked Quora blog:


If you are scared: Seven tips for dealing with doomsday fears which also talks about health professionals and how they can help.

If in the middle of a panic attack, see


Tip, bookmark those links to search for debunks more easily. Here is a screenshot of my bookmarks


Facebook group Doomsday Debunked has been set up to help anyone who is scared by these fake doomsdays.

Wiki Doomsday debunked wiki


Do message me on Quora or PM me on Facebook if you need help.

There are many others in the group who are available to support scared people via PM and who can also debunk fake Doomsday “news” for you if you get scared of a story and are not sure if it is true. See our debunkers list

If you are suicidal don’t forget there’s always help a phone call away with the List of suicide crisis lines - Wikipedia