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Monarch Butterfly population plummets to fewer than 2,000 in 2020


This is not a drill. California is poised to lose the Western monarch butterfly and its mysterious annual migration from the continent’s Western regions to the coastal areas between Baja and Mendocino.

The list for blame is long — habitat destruction, insecticides, herbicides and, yes, good intentions, because if you’ve ever planted a showy orange and red milkweed in Southern California with the goal of helping the monarch, consider yourself part of the problem.

So why should we care? First off, caterpillars are a critical food source for most songbirds, which rely heavily on the insects to feed their young. Second, butterflies, like bees, are important pollinators. Adult monarchs sip nectar from many blossoms, and as they flit among flowers, they are also spreading pollen, helping the plants produce seeds, which also feed birds and other wildlife and, of course, help the plant reproduce.

And third, butterflies are just plain beautiful, especially the monarch with its orange wings rimmed in black with white dots. Can our world really afford to lose something so miraculous? Fortunately, there are things SoCal gardeners and plant parents can do to help monarchs survive, such as eliminating any use of pesticides or herbicides on their property — but first, a little background:

Eastern monarch butterflies are well known for their famous migration from the Eastern and Central regions of the United States to Mexico each winter, where they congregate by the thousands to mate and stay warm. Their numbers have dropped significantly, from 384 million in 1996 to 60 million in 2019.

But their cousins, the Western monarchs, have seen a more terrible decline. Western monarch numbers have been steadily dropping for decades, from 1.2 million in 1997 to 30,000 in 2019, but the most recent results from the 24th Western Monarch Thanksgiving Count are staggering — just 1,914 butterflies total, down from the millions that used to migrate from the Pacific Northwest and Central California to overwinter along the coast from Mendocino in Northern California to Ensenada in Baja California. One of the most disturbing finds from last fall came after wildfire ripped through the area around Pacific Grove, aka Butterfly Town, USA, in the midst of traditional migration season. During the Thanksgiving count, not a single monarch was found in Pacific Grove, a tourist mecca for people who come to marvel at the swarms of Western monarchs that congregate during the winter, clinging to eucalyptus and pine branches to find protection from the cold and wind.

Pacific Grove Monarch Butterfly Sanctuary in 2016, when 17,100 monarchs were counted at the sanctuary. -Connie Masotti

Read more at the source.


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