Monarch Migration News September 18, 2014

Unseasonably cold temperatures this week shortened daily flights, but the monarchs pressed on. From vantage points across the continent, people described the behavior they observed as monarchs traveled overhead — or settled down to roost.

Monarch Butterflies Roosting in Iowa During Fall Migration
News: A Cold Week
On the northern Great Plains, monarchs waited out the cold under a crystal clear sky and a waning gibbous moon:

"Found 120+ monarchs in the mid afternoon! They were already clustering together in our north grove trying to stay out of a strong and chilly southwest wind." Hartley, Iowa  Sept. 13, 2014

Spectacular Exodus
Despite the unseasonable cold, monarchs continued their dramatic departure from the Great Lakes region. In a steady stream, they pressed southward when temperatures met flight threshold.

People noticed how cold temperatures affected migration. Monarchs began to travel later in the morning and formed roosts earlier in the afternoon.

"We conservatively counted 1,000 monarchs from 11 a.m. to 2 p.m., at 4 - 8 per minute. Then the sun went behind clouds and all stopped!" Scarborough, Ontario   September 15, 2014

"An estimated 500 monarchs were gathering in Sunnyside Park on the north shore of Lake Ontario in Toronto. As the day became cooler the monarchs were collecting in the upper branches of the willow trees. I had observed them throughout the day floating through the south end of the city, just above the lake." Toronto, Ontario   September 14, 2014

"Our class is very excited because we just keep seeing monarchs all day long — from our classroom window, from the school library, and while outside playing."
Church Street PS   Toronto, Ontario  Sept. 17, 2014

Funneling Toward Mexico
Look at the peak migration map now and you can clearly see the monarchs are heading toward Mexico. They're crossing the continent to find the traditional overwintering region, a place they have never been.

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Next Update September 25, 2014