By Amy Cherry/Allan Loudell 6:16pm, July 30, 2013 - Updated 5:36am, July 31, 2013
Photo courtesy of the Delaware Nature SocietyThe number of monarch butterflies spotted this summer has hit an all-time low.
The Delaware Nature Society's annual butterfly census shows the number of monarchs falling dramatically over last summer.
Lincoln Brower, biology professor at Sweetbriar College, tells WDEL one of the reasons.
"The forest where monarchs over-winter in Mexico have been badly logged and deteriorated. The Mexican government has mitigated that recently, but there's still logging going on, and the monarchs spend the winter in Mexico in these forests that provide a blanket and umbrella effect, protecting the butterflies," says Brower.
Another reason? Broward notes when corn and soybean crops are sprayed, the pesticides kill the milkweed, which is a major nectar source for breeding monarchs.
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