Why should we care about insects?
How? Insects perform many vital services:
- 80% of wild flowering plants and many human food crops, including 75% of fruits, nuts and seeds grown for human consumption, are pollinated by insects. Honey bees alone pollinate $30 billion worth of crops per year.
- Insects play a key role in aerating the soil and recycling nutrients. Many insect species feed on dead organic matter such as fallen trees, animal carcasses or poo. Without them all this material would accumulate, creating a real mess.
- Many types of insect prey on, or parasitize, other species which we label as “pests” because they cause harm to humans or to things which we value. Only 1 – 3% of insects are considered pests, while others can help by acting as biological controls, reducing the need for harmful chemicals.
- Insects provide food for many other animals: birds, reptiles, amphibians and mammals. They could be more widely used as a sustainable protein source for humans too.
Insects are extraordinarily diverse: over one million species have been scientifically identified, making up 80% of all known species. There are approximately 1.4 billion insects for every person on Earth, and their combined weight is 70 times that of all the people.
Many insect populations are in decline, however, due to human pressures especially habitat destruction, degraded habitat quality, intensive farming and the use of chemical pesticides. In the longer term, climate change poses an even greater threat, which will play out in many different ways across the globe.
In 2017, the results of a long-term study in Germany were published which caused serious alarm. The study had investigated total flying insect biomass at 63 protected nature areas in Germany, from 1989 to 2016. The results indicated a decline of 76% in arial insect biomass over the 27 years, with an 82% decline in the mid-summer peak. It should be noted that samples were not collected repeatedly at each site, as this itself would have caused a negative impact on the biomass. 37 locations were sampled only once, 20 locations in two of the years, five locations in three years and one in four years. The 63 sites were representative of Western European low-altitude nature protection areas, embedded in a human-dominated landscape, and included a mixture of habitat types.
This was the first study which had attempted to measure total insect biomass over a prolonged period. Amid fears of an “insect apocalypse”, the largest study to date on insect population change was then completed in 2020. Drawing on data from 166 long-term surveys across 1,676 globally distributed sites, it painted a more complex, but still negative, picture of the state of insect health.
This meta-analysis found that on average, insects such as butterflies, ants and grasshoppers are declining by 0.92% per year, i.e. 9% per decade. While not as bad as some reports, it is still alarming: over 30 years it means a quarter less insects. And because it’s a global mean, some places are much worse: the biggest losses have been in the US West and Midwest and in Europe.
On the other hand, populations of water-based insects such as mayflies and dragonflies have actually recovered in western and central Europe since the 1970s, because of legislation such as the Clean Water Act, which cleaned up rivers and lakes. This shows that conservation actions really can work. Success in this specific area, however, will not compensate for losses as the vast majority of insects are land-based.
Pesticides: Farming’s chemical weapons
There has been much publicity about the threat to beneficial insects and particularly honeybees, from exposure to a widely used class of chemicals called neonicotinoids. These are systemic pesticides which once sprayed on a plant, penetrate every part including its nectar. Low-level exposure to neonicotinoids has been linked with Bee Colony Collapse Disorder (CCD), a phenomenon in which all adult bees except the Queen disappear from the hive. While many factors are involved including parasites and pathogens (disease-causing organisms), poor nutrition and lack of genetic diversity, it is clear that exposure to pesticides weakens the bees leaving them more vulnerable. While the rate of CCD has declined in recent years, various forms of bee colony loss are still a major international concern.
In 2013 the EU took action by restricting the use of certain neonicotinoids to plants which are not a food source for bees. Meanwhile, most EU countries have been cutting their pesticide use. But not Cyprus.
In 2018 the Pancyprian Ecological Agricultural Association warned that bees were disappearing at an alarming rate, saying some areas had seen the disappearance of more than 85 per cent of the bee population. The association condemned “the outrageous and illegal use of pesticides that are on the rise during this period, which have a series of negative effects, which, with the way we are going about it, may be irreversible.”
As a haven for insects and other wildlife, Cyprus has many advantages. The land is not highly urbanized or industrialized, much of its terrain is too mountainous or hilly for intensive farming and the range of altitudes from sea level to the Troodos provides a great variety of habitats. An overriding problem, however, is water scarcity. Cyprus is the most water-stressed country in Europe and as a result, wild species must compete with humans for access to water on which all life depends.
To maximize water retention, Cyprus has constructed a total of 108 dams and reservoirs. In relation to its land area, it has the highest number and capacity of dams in Europe. Dams do provide a buffer against periods of drought but at great cost to the valleys downstream which lose their water flow. In an already arid land, this results in depleted plant life, fewer flowers for nectar-feeders, no breeding habitats for aquatic species and much less food for birds and other animals. The built reservoirs are a poor substitute for natural habitats, as their water levels are often too variable for vegetation to become established on the banks and for local ecosystems to develop.
There is no easy answer to this, but it is worth noting that the domestic sector, including tourism, only consumes 25% of Cyprus’ water. A whopping 69% is used for agriculture, which contributes only 3% of GDP. Moreover, half of the water used for farming is groundwater which is being pumped up at an unsustainable level, causing problems such as the incursion of sea-water into the aquifers. There is surely scope for improved agricultural practices which would be less water-intensive, and for some land to be reclaimed from farming and restored to nature.
Much of Cyprus’ natural heritage has been gravely damaged, but habitats can recover given the right help. On a global level, the UN has designated 2021 – 31 as a decade for Ecosystem Restoration. With Europe recognized as one of the most nature-depleted areas, the EU recently held a public consultation exercise about calls for 15% of all member countries’ lands to be restored to a natural state. Cypriot conservation bodies have backed this, calling for legally-binding measures to be put in place. Measures which would force the removal of a few of Cyprus’ dams and allow the natural life of the valleys to be restored.
What can you do to help insects, especially the beneficial ones?
Provide food:
- Include a variety of native plants to provide food sources such as nectar
- Make space for wildflowers – there is really no such thing as a weed, only unwanted wildflowers.
Provide shelter:
- include a mixture of features like ground cover plants, dead leaves (which will also hold moisture in the soil and replenish nutrients) areas of bare soil, and maybe even an “insect hotel”
Protect insects so they can help you in return:
- Avoid using harmful chemicals such as pesticides and herbicides
- Decide how many pests are tolerable: some pests are necessary to feed beneficial insects, and some plant damage is natural in any ecosystem
- If you have to use a pesticide, try to choose a targeted one rather than a broad-spectrum insecticide which will kill everything.