Silent skies

Why is it that birds are falling from the skies, their numbers crashing in mass extinctions? Henk Tennekes has an answer: He cites evidence in his book that the species suffering dramatic losses (mostly out of public view) in the past two decades -- sparrows, swifts, starlings, and many other insectivores -- are struggling to find food; insects such as beetles, springtails, and earthworms are being wiped out by neonicotinoid insecticides, chiefly imidacloprid and clothianidin.

"The excessive imidacloprid levels noted in surface water of ... [places] with intensive agriculture have been associated with insect decline and [subsequently] a dramatic decline of common grassland birds."

The author, a toxicologist in the Netherlands, documents the threat neonicotinoids pose, even at very low levels, their mode of action similar to that of chemical carcinogens. These persistent nerve poisons, applied since 1991 as systemic seed and soil treatments, cause ecological damage in two major ways: They kill insects of all kinds by devastating their nervous systems, and they migrate from soil into waterways, then dispersing throughout local ecosystems.

The cumulative impact of systemic insecticides on bees is addressed in the earliest sections of the book as a stern reminder that the security of the global food supply is at risk. We know that some growers in Maine are paying attention, since the contractor who trucks hives here to pollinate blueberries will not subject his bees to crops on which neonicotinoids are applied. Although blueberry growers therefore do not rely on neonicotinoids to repel insects on their fields, this class of chemicals is widely used on other food crops as well as on trees, ornamentals, and turf. Tennekes points out that given the rapid spread of these persistent neurotoxins in the environment, once they are released, half-measures are not adequate to protect bees from exposure to them. Only prohibition will stem the crisis of colony collapse, and indeed such unconditional action has been taken in several regions of the world.

Systemic Insecticides is a carefully referenced academic paper with nontechnical summaries at the beginning and end, and with remarkable landscape paintings reproduced within its pages. The artist collaborator is Ami-Bernard Zillweger, who paints wide-angle views of wildlife habitat and agricultural fields, along the edges of settled areas, that remind us how much is at stake. These are pictures with radiant atmospherics, but the signs of impending collapse are coming with ever less subtle warnings: " ...[C]ontamination with persistent insecticides that cause irreversible and cumulative damage to aquatic and terrestrial (nontarget) insects must lead to an environmental catastrophe. The data presented here show that it is actually taking place before our eyes, and that it must be stopped."

Source:
Jody Spear, Maine Organic Farmers and Gardeners Association, January 2011