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A lot of people have stopped reading the news because they can't stand it any more. So here's a happy story for a change. The monarchs are back! Three weeks ago, I saw one alighting on a milkweed plant in our field in rural Ontario. Since then we've had almost daily sightings.

What a relief. We hadn't seen a monarch butterfly in years. These gorgeous creatures were widely reported to be headed for extinction – one more victim of humankind's relentless assault on the planet. We'd begun to wonder if they'd ever come back. And now, here they are, alive and well, and the future is looking surprisingly bright.

"This looks to be a good year for monarchs," writes Chip Taylor on his blog at Monarch Watch, a Kansas-based non-profit that is dedicated to monarch conservation. He says the fall migration season is shaping up to be the best in years.

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What happened to the monarchs? The popular story is that genetically modified crops and an evil herbicide called glyphosate (also known as Roundup) are to blame for killing the butterflies. In other words: Monsanto did it.

The monarch is probably the world's most charismatic insect. So it was inevitable that hysterical environmental groups would catastrophize its very real problems in order to bash the usual villains. "What we're looking at is a future without butterflies," warned Rick Smith, former executive director of Environmental Defence Canada, back in 2006. The Union of Concerned Scientists once claimed that butterflies were dying from toxic pollen. Two years ago, the Natural Resources Defence Council even sued the U.S. Environmental Protection Agency for "dragging its feet on efforts to save the imperilled monarch."

In fact, glyphosate doesn't kill monarchs. It kills the milkweed plants where they lay their eggs. Although environmental groups have romanticized milkweed as a native wildflower, it's a big problem for crop farmers, who regard it as an invasive pest. Until recently, farmers in Ontario were obliged by law to eradicate it. The effect of glyphosate on the monarch population is an unintended consequence of greater farm productivity, which, over all is a good thing.

Loss of milkweed habitat is an important factor in the monarchs' decline. But things are more complicated than that. Temperatures, wind, rain and extreme weather can also affect the monarch population. In 2002, hundreds of millions of monarchs were wiped out by a severe storm. Last year, just as they were on the verge of a comeback, another storm hit their overwintering grounds in the mountains of Mexico. Their tiny winter habitat is also under threat from deforestation.

Sadly, the monarchs aren't alone. Because of habitat loss, butterfly populations worldwide are in decline, even in regions where genetically modified crops play no role at all.

The monarch population seems to have bottomed out around 2012-13, and has since been making something of a comeback. (Population records have only been kept since 1994, so we don't know what the natural fluctuation may be over a longer period of time.) Monarch Watch and other groups have been promoting more milkweed planting on roadsides and other unfarmed land that lies along the butterflies' migration routes. This is a good thing. But the sharp rebound in the monarch population also coincides with a soaring use of glyphosate, which suggests that something more than a herbicide is responsible for the monarchs' changing fortunes.

The monarch story is a lot like the bee story. Remember that? The honeybees were dying, we were told. The villain was neonicotinoids, a new kind of insecticide that had induced a bee holocaust. But then the bees bounced back. A body of research found that neonicotinoids were at best a minor factor in the bee blight. Nature is more complicated than we thought. And agricultural progress is less evil.

The monarch migration is a sight to behold, as I can tell you. One fall, my husband and I headed down to Point Pelee, at the southernmost tip of Canada. We watched the monarchs fly in from all over, getting ready for their big trip across the lake and eventually to Mexico. Their staging point was a single bush at the tip of a sandspit. Each butterfly would land on that bush before taking off. And each fall their great-great grandchildren would do the same thing all over again. Nature is more miraculous than we could possibly imagine. Maybe it's more resilient, too.

New structures in Townsend, Ontario were built to house barn swallows after the crumbling buildings where they lived were demolished. The population of the birds dropped by 65 per cent between 1966 and 2009 in the province.

The Canadian Press

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