Bugs get a bad rap, but many help humans
To many people, the only good bug is a dead bug. What I am trying to say is that most insects get a bad rap.
Humans need to broaden our understanding when separating the bad insects from those that are good or just a little ugly. A first step is realizing just how many insects and other many-legged creatures actually live on this little planet of ours.
Most animals are insects, and most insects live in the tropics. But it is pretty tough to figure out just how many insects that live in tropical forests. Sampling of insect communities is really challenging--almost every square inch of the forest can harbor entirely new species, and many are easily overlooked.
A few months ago, a group of scientists made an effort to put a number on the elusive: More than 100 scientists from around the world devoted time to counting the number of insects in a Panamanian forest.
In these little patches of forest, they collected more than 129,000 insects, representing more than 6,100 species. Most of them (60 to 70 percent) were new to science. That's a lot.
From this data, and with a wave of their statistical magic wand, they were able to confirm a prior estimate that there are around 6.1 million insect (and spider) species on Earth!
Entomologists estimate that worldwide, between 1,000 and 3,500 insect species can be considered pests. These pests inflict billions of dollars in damage to crops and human health every year, and we need to manage these pests to protect our interests.
But for every pest insect, there are between 1,700 to 6,000 insect species that are either helping humans or are contributing to ecosystem health, often in ways we don't understand yet. One estimate is that these non-pests contribute approximately $57 billion in services every year in just the United States.
Another important point is that insect diversity isn't just important in the tropics; biodiversity in prairie and grasslands of the Great Plains are equally important.
Recently, a graduate student at South Dakota State University, Ryan Schmid, conducted a fairly intensive survey of the insects in prairies, pastures, and cornfields of eastern South Dakota. On two dates at three locations (for each habitat), he found around 347 insect species (not counting spiders, which probably would have added dozens more species). That is a tremendous diversity given the sampling effort; nearly all could be considered as beneficial or harmless to humans. Pest management decisions in our region have real implications for this diversity.
I think it is time to put our aversion to the few problematic insects in perspective. Pest management shouldn't throw the baby out with the bathwater; controlling a few pests should not come at the expense of the beneficial species, simply because we don't understand the benefits they are providing us.