Number Of Monarch Butterflies Wintering In Mexico Down 53% From Last Year
The number of monarch butterflies wintering in Mexico is down by more than half this year, according to new survey results. The National Commission of Protected Natural Areas of Mexico, together with WWF-Mexico, local communities, and other partners, conducts a survey every year to document the extent of forest habitat covered by monarch butterflies that migrate from the US and Canada. The area of forest inhabited by monarchs in Mexican forests is used as a proxy for estimating the monarch butterfly population.
The survey found that the area of forest occupied by monarch butterflies during the 2019-2020 winter season was just 7 acres (2.83 hectares), a 53% decrease from the 2018-2019 season, when monarchs covered 15 acres (6.05 hectares) of forest.
In a statement, Jorge Rickards, the managing director of WWF-Mexico, said that the decline in the monarch butterfly population wintering in Mexico is not necessarily a cause for alarm, but added that we must remain vigilant and not allow it to become a trend in the coming years. Conservation is a long-term job.
WWF reports that when migrating monarchs arrived in Southern Texas in March and April 2019, they were met with lower temperatures than normal, which impeded the growth of eggs and larvae. That meant that there were fewer butterflies to produce succeeding generations of monarchs, causing a smaller population to occupy a smaller area of Mexicos forests.
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https://news.mongabay.com/2020/03/number-of-monarch-butterflies-wintering-in-mexico-down-by-more-than-half/