Although the number of monarchs overwintering in Mexico has increased from last year's record low, the population remains 80% below the historic average. There are 57 million monarchs compared to a long-term average of 300 million and peak of 1 billion. The clustering butterflies cover less than 3 acres of forest compared to a peak of 51 and an average of 15 acres. Half of this year's monarchs are residing in only one of the 12 traditional sites.
Monarch numbers are down and people are wondering why. This article examines the factors that caused the decline during the past year and the downward trend over the past decade. Also, see how you can help.