Thursday, May 23, 2019

Endangered Bugs?


The ice, it seems, was scarcely off the lakes when the bugs were back.

Morning frost warnings and the absence of any semblance of daytime warmth has not postponed their return. The critical question now is how numerous they will be.

Will they be thick as a winter blizzard or thin as scattered snow flurries? Possibly thin and getting thinner if you read and believe recent scientific studies.


An Australian review of 73 scientific studies of insect decline has concluded that the total mass of the world’s insects is declining by “a shocking” 2.5 per cent a year. This rate of decline might lead to extinction of 40 per cent of the world’s insects over the next four decades, says the review.

“It is very rapid. In 10 years you will have a quarter less, in 50 years only half left and in 100 years you will have none,” says the review’s author, Francisco Sánchez-Bayo, at the University of Sydney, Australia.

Some might cheer at that, and perhaps even hope for a faster decline. It is difficult to feel empathy for black flies, mosquitoes and the like in our part of the world. They are nuisances with little apparent purpose.

Bugs, in fact, are a critical part of our world’s biodiversity. They are important pollinators, helping to produce the food we eat. They are food for birds and some animals and are  environmental stewards in that they eat dead matter and clear away waste.

In an earlier column I referred to E. O. Wilson, the American biologist and expert on insect life. His quote, mentioned then, is worth repeating: “If insects were to vanish, the environment would collapse into chaos.”

The importance of insects on other species can be seen in world bird populations, which also are declining at an alarming rate. Last year’s State of the World’s Birds report said that 40 per cent of the world’s 11,000 bird species are in decline, and that one in eight bird species is threatened with extinction.

Shrinking insect populations are not a major reason for decreased bird numbers but they are a factor. Agriculture, logging, invasive species and climate change are listed as major causes.

Agriculture is converting forests into farmland less suitable for both birds and insects. Both are being hurt by the use of chemicals in agriculture, notably in pesticides,

Evidence of this is seen in the U.S. where more land is being converted for grain production, especially corn for biofuel. The review says that between 2008 and 2013 wild bee populations declined 23 per cent, the same period during which farming for biofuels almost doubled.

Also, between 2008 and 2011 more than eight million acres of grasslands and wetlands were converted to corn production. That figure comes from the Environmental Working Group,  a controversial American activist group that specializes in research and advocacy in agriculture and toxic chemicals.

It is not reasonable to simply blame agriculture for declines in insect and bird populations. The issue is much more complicated and is really about overall habitat loss due to a variety of factors: urban growth, food and biofuel production, filling in wetlands, cutting down forests, pollution, and climate change.

A best first step to stopping or reducing species decline is awareness. How can we reasonably modify our lifestyles to lessen our negative impacts on the planet?

(A tiny step forward would be to persuade folks to stop tossing their garbage out their car windows. Haliburton County is without doubt the worse area for this anywhere I have lived in Canada, and I have lived in a lot of places).

Steep declines in some species – in fact mass extinctions – have occurred before. Meteor strikes and volcanic eruptions have wiped out huge numbers of insect species in the past but insect diversity always has recovered, even though it might have taken thousands of years.

We can’t do much about preventing natural occurrences such as volcanic eruptions and meteor strikes. But we can help all the other species around us by thinking about how our actions affect them.

We all hate the buzzing and biting of mosquitoes, black flies, deer flies and other nuisance bugs. But I don’t think any of us would like the barrenness and bleakness of a world without them.


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