Most of the news about monarch butterflies for the past 20 years has been bad news, led by the documented declines in monarch butterfly populations. The recent news about monarch butterflies has been mixed.
Monarch butterfly winter population increased! A traditional measure of the monarch butterfly population has been to estimate the area of forest in south central Mexico covered with overwintering monarch butterflies that arrived there from the upper Midwest and eastern U.S. The total area occupied by overwintering monarchs was over 18 hectares during the winter of 1996-1997. The all-time smallest recorded area was only 0.67 hectares in the winter of 2013–14.
In late February, the World Wildlife Fund Mexico announced the total forest area occupied by overwintering monarch colonies was 4 hectares, a dramatic increase over the previous winter's slight population rise. (World Wildlife Fund)
The overwintering population increase is welcome news, but the populations remain significantly below historic levels and monarch conservation efforts must continue.
The monarch northward spring migration has begun. Journey North and others are reporting that monarch butterflies are in the beginning stages of their flight northward, though the mass movement out of southern Mexico toward northern Mexico and southern Texas has not yet begun. (Journey North, March 10, 2016)
The northward movement of monarchs and their arrival in the Midwest can be tracked on a citizen science, interactive map on the Journey North website.
Late March storms harm monarch butterflies in Mexico. A powerful storm with rain, hail, snow, sub-freezing temperatures and high winds struck the monarch overwintering region of southern Mexico on March 10, causing heavy losses (Journey North). Favorable weather and abundant food plants in the summer breeding range will be needed to help the population continue to rebound.
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