A rare spectacle awaits anyone who goes out on the coast on a warm day this year. Monarch butterflies -- the orange and elegantly spotted "king" of the beautiful insects -- are overwintering in numbers 10 times or more than usual.
"It's absolutely phenomenal. It's hugely more than I've ever seen before," said James Island wildlife ecologist Billy McCord, who specializes in the gorgeous butterfly.
On a Christmas Eve visit to Patriots Point, he saw about 500 monarchs and netted about 170. Normally, McCord would tag about 50 individual monarchs at the Mount Pleasant tourist destination over the course of a winter.
So far, he's tagged more than 590.
And it's not just Patriots Point. McCord has seen more monarchs at all the coastal island sites he's gone to this winter. He's also tagged 420 individual monarchs on Folly Beach.
The annual migration of swarms of monarchs is one of those awe- inspiring natural mysteries -- clusters of sweeping wings with a span wider than a baseball. Along the East Coast, the butterflies are thought to migrate back and forth from as far as Canada largely to South Florida and the Caribbean.
If that weren't amazing enough for an insect as light as a hair, the monarchs that show up each year are grandchildren or great-grandchildren of those from the year before.
The butterflies aren't federally listed as threatened or endangered, but are thought by conservation groups to be in jeopardy because of habitat loss to development and climate warming.
From late October through November, swarms reach the Lowcountry coast and roost in the evenings on flowering bushes.
Monarchs have been shown to migrate following the angle of the autumnal sun.
At one point or another, the sun gets too low, and they quit moving, McCord said. So each year, some of the later-arriving monarchs reach the Lowcountry and don't go any farther.
They also won't move when winds are 20 mph or more. High winds along the East Coast evidently delayed departures and movement this year, McCord said.
The biggest swarms didn't arrive here until into November, and more butterflies apparently stayed.
High numbers of repeat captures of monarchs tagged earlier in the season indicate to McCord that that's happening, he said.
The butterflies like to winter in Patriots Point because of higher temperatures along the water's edge, humidity that helps keep them moist, forest edges and lawns that provide roosts and dandelions for nectar. He expects to see one or two hundred when conditions are right.
"It's actually spectacular if you go out to Patriots Point on a warm day," he said.
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