Is modern agriculture’s toxic hold on nature becoming a death grip?
By Larry Powell
This summer, the tragedy of dying pollinators took on a new dimension. A team of Dutch researchers found that, in addition to bees, “significant declines in populations of insect-eating birds are also associated with high concentrations of neonicotinoids.”
Another insectivorous species in decline, the purple
martin. Are they becoming "neonic" victims, too?
“Neonics,” as they are commonly called, have become the most widely used group of insecticides in the world – and, the most infamous. As well as killing the crop pests they are supposed to, they’ve been implicated in the deaths of billions of honeybees from near and far, for well over a decade. The European Union even clamped a two-year moratorium on their use, last year.
Various formulations of the chemical are made by multinational corporations like Bayer CropScience, Syngenta and Monsanto. They’re used as seed dressing on crops ranging from canola, soya and corn, to potatoes. They are “systemic” poisons. That means they penetrate all part of the plant, even the nectar and pollen. But as little as 2 percent of the plant takes up the active ingredient. The rest gets washed off, contaminating both soil and water. “Neonic” use exploded onto the farm scene about two decades ago, on crops that now cover vast areas of the world’s farmlands.
The study, by scientists at Radboud University, was published in the journal, Nature. It concludes, the most widely-used “neonic,” imadacloprid, poisons not only insects harmful to the crops, but others which form an important part of the birds’ diets, especially during breeding season and while raising their young. These would include grasshoppers, butterfly caterpillars, mosquitoes, midges and mayflies (an important food source for fish, as well as birds).
“In the Netherlands, local (bird) populations were significantly more negative in areas with high surface-water concentrations of imadacloprid. In those cases, bird numbers tended to decline some 3.5% per year. (This would translate into a staggering loss of about 35% in a decade!) These declines appeared only after the introduction of imadacloprid to the Netherlands in the mid ‘90s. Our results suggest the impact of neonicotinoids on the natural environment is even more substantial than has recently been reported and is reminiscent of the effects of persistent insecticides in the past.”
This is an apparent reference to DDT,another persistent insecticide. It was banned in North America after Rachel Carson’s book, “Silent Spring,” exposed it in the 60s for the mass die-offs of both birds and fish on the continent. She also revealed its widespread and dangerous presence in various human organs.
Birds are much less vulnerable to neonics than insects. So, it is believed avian numbers are declining, not because of direct poisoning, but because the chemicals are killing off the insects they normally eat.
“A route to direct mortality.”
But, it’s also unlikely any bird that directly eats seed treated with “neonics” will stand a chance. One study concludes, “A single corn seed can kill a songbird.” Another finds, “Consumption of small numbers of dressed seeds offers a route to direct mortality in birds.” And some of the bird species included in the Dutch study, like starlings and skylarks, eat grain as well as insects.
Is this just a “faraway” problem? Not really!
(4) Last winter, a biologist at the University of Saskatchewan sounded a very similar alarm. Christey Morrissey is about halfway through a four-year study of the chemical in question. She told the CBC, “Huge amounts of “neonics” are leaching into the millions of potholes that dot the landscape of the Canadian prairies. This can have potentially devastating impacts on aquatic insects such as mosquitoes and midges, both important food sources for birds. She says levels of the poison in the water have been found to be anywhere from ten to a hundred times above limits which are considered safe!
Meanwhile, she notes, populations of insectivorous birds such as barn swallows, have plummeted some 70 percent over the past 30 years. She concedes other factors, like habitat loss, are contributing to the decline, too. But she still believes neonics are playing a significant role.
The Dutch study team suggests, “Future legislation should take into account the potential cascading effects of neonicotinoids on ecosystems.”
Ms. Morrissey offered this observation to the CBC.
“We all want to have food that we consume and enjoy. But, at what cost? Is that the cost of having no more birds around? Of having no more butterflies? Having no bees? People are thinking about that now.”