Here is an ocean of butterflies, 70 miles wide, captured on radar over Colorado

https://www.dailykos.com/stories/2017/10/6/1704785/-Here-is-an-ocean-of-butterflies-70-miles-wide-captured-on-radar-over-Colorado?detail=emaildkre

An enormous migration of painted lady butterflies was captured by a Denver weather radar. There are more images, which you can see on the Denver Star, and they are pretty extraordinary. It was so extraordinary that the first person to see the 110 kilometer (68.35 miles) spread wasn’t sure what he was looking at.
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OAKLAND, CA - APRIL 11: A Painted Lady butterfly rests on a flower April 11, 2005 in Oakland, California. The heavy rains that pounded California over the winter have resulted in bumper crops of both thistles and wildflowers throughout the state and are attracting millions and millions of migrating Painted Lady butterflies that lay their eggs on thistles and, as adults, avidly feed on the nectar of a wide range of wildflowers. The last similar migration was in the spring of 1992, which also followed a particularly wet winter. (Photo by Justin Sullivan/Getty Images) The painted lady butterfly

Paul Schlatter of the National Weather Service said he first thought flocks of birds were making the pattern he saw on the radar Tuesday, but the cloud was headed northwest with the wind, and migrating birds would be southbound in October.

He asked birdwatchers on social media what it might be, and by Wednesday had his answer: People reported seeing a loosely spaced net of painted lady butterflies drifting with the wind across the area.

Schlatter said the colours on the radar image are a result of the butterflies’ shape and direction, not their own colours.
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