| "The direction and strength of the winds largely determine the progress of the migration," says monarch biologist Dr. Bill Calvert. This week observers reported ways the wind can be a help—and also a hazard:
Hugging the Coast
Coastlines are a great place to watch fall migration because the wind often funnels monarchs there. Flying along the coastline is a monarch's last-ditch effort to avoid the dangers of crossing open water.
"Witnessed hours of monarchs heading west along Lake Ontario shoreline." 9/7/12 Webster, NY
"Saw scores of monarchs, mostly within 100 yards of the beach, all flying parallel to the coast." 9/10/12 Wainscott, NY
"Hundreds of monarchs were arriving at Marshall Point lighthouse during the afternoon. The remnants of storm Isaac had the wind blowing NW at 20-30 kts. Butterflies were flying against this and, upon making landfall at the lighthouse, filled the trees and shrubs as they rested after their flight from the Maritimes and offshore islands of Maine." 9/5/12 Port Clyde, ME
Stranded on the Coast
Sadly, after powerful winds carry monarchs offshore people often find dead butterflies washed up on the beaches. This picture of 50 monarchs was taken beside Lake Michigan:
"We think they were attempting to cross the lake and got caught in last night's storm," wrote Moya of Schlitz Audubon Nature Center.
Tagging data provides further evidence that wind and water are a signficant migration hazard. According to a study by Davis and Garland, monarchs tagged along the Atlantic coastline have an extremely low recovery rate at the Mexican overwintering sites.
Watch the Wind!
Where is the wind affecting monarch migration today? Bookmark this wind map and and watch it live.
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