Insects Make Better Friends than Foes
As a child, I was an avid collector of insects. Back then, I wasn't aware that they are the most numerous, successful and important animals on earth. I was simply fascinated by their diverse forms and beauty, especially beetles.Still, for most people, insects inspire revulsion rather than awe, and few creatures on this earth are as maligned. We poison them, step on them, swat them and fear them. They invade our dreams as well as our crops - a plague, a scourge to be eradicated, wiped out and cleansed from the earth.
But no matter how hard we try; we can never rid ourselves of our little nemeses. They are built for survival and will continue on in spite of our efforts. It's been said that for every human on the planet, there are at least 200 million insects. In spite of all our technologies, all our knowledge and power, this world really belongs to them - not us.
And yet, although they have a well-earned reputation as crop-killers and disease spreaders, insects do far more good than harm. They keep systems functioning on our little planet by breaking down organic matter, pollinating flowering plants and providing food for fish, birds and mammals.
For those of us living in cities, such services may not seem like such a big deal, but in nature they are irreplaceable. Unfortunately, natural services that cannot be replaced are often taken for granted, as though they provide no real value to our economy or our livelihoods. These free-of-charge services don't fit neatly into our way of calculating the bottom line, so they are usually ignored (economists call them an "externality.")
However, a recent study conducted through Cornell University attempts to assign a dollar figure to the services provided by wild insects. The findings, published in the journal Bioscience, conservatively estimate that these services are worth at least $57 billion USD to the American economy every year.
This figure only includes four services: dung disposal, control of crop pests, pollination and providing food for wildlife, like birds. It does not include many less-obvious or hard-to-calculate services, nor does it include domesticated insect labours such as the honey made by domesticated bees. Had these also been included, researchers say the total would be in the hundreds of billions.
Bees alone are thought to pollinate close to $3 billion worth of fruit and vegetables every year. The U.S. Department of Agriculture estimates that over 30 per cent of all the food eaten in the U.S. comes from insect-pollinated plants - including almonds, apples, cucumbers and tomatoes. The value of pollinators made news in 2003 when California's almond crop took a beating because there weren't enough insects to pollinate them, forcing growers to import bees from as far away as Australia.
Bugs also save farmers serious money by eating pests that would otherwise be eating their crops - some $4.5 billion every year. This service not only prevents crop loss, but also reduces the need for expensive and toxic pesticide applications. Dung beetles also help reduce illness in farm animals by removing and processing disease-spreading waste.
According to the report, by far the most economically valuable service provided by insects (at least, the most readily quantifiable) is as a source of food for other wildlife. Many outdoor recreational activities, from hunting to fishing and birdwatching, depend either directly or indirectly on insects as the main source of protein in the food chain. This service alone is estimated to be worth more than $50 billion a year.
Unfortunately, not all is well in the insect world. Diseases, parasites, insecticide use and loss of habitat have resulted in substantial die-off offs in beneficial insect species, such as bees. In fact, five species of bumblebee have disappeared from the U.S. in the past six years.
Whether we like them or not, bugs are with us for good. Rather than killing them indiscriminately, we'd be better off looking for ways to increase the numbers of those insects that provide us with so much, while keeping the real pests at bay.
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