Monarch Migration News: January, 2016
By Elizabeth Howard
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The overwintering season in Mexico is underway and good news is predicted: Monarch numbers appear to be up substantially from record lows.

Monarch Butterflies
Felipe Martinez Espero

 
News: Waiting for Population Measurements

Good News Predicted
This year's population will be measured in December, when the monarchs are densely concentrated in their clusters. Results may be released as early as this month. Monarch numbers are expected to have increased substantially from the record lows of the past 3 years.

How Much Larger?
Predictions of a 4-fold increase over last year have been reported in the Mexican press, but estimates made before the monarchs cluster tightly are likely to be inflated.

We predict the population will be twice as large as last year based on Journey North's fall migration data. Based on tagging data, Dr. Chip Taylor of Monarch Watch also predicts the population will have at least doubled. He noted that, since conditions this breeding season were similar to those of 2011, he wouldn't be surprised to see the population reach the level of 2011 (2.89 hectares).

We'll post the news as soon as it's available!

 
Monarch Butterflies
Population Size
 
Monarch Butterflies
Wintering Sites
Winter in Mexico: Month-by-month Highlights
November   December
Monarch Butterflies arriving in Mexico   Scientists visit the 12 wintering sites and measure the surface area the colonies cover.
Arriving
Throughout the month, monarchs continue to arrive from the north and settle in at the 12 traditional wintering sites.
  Being Counted
Scientists visit the 12 wintering sites and measure the surface area the colonies cover. Results should be released in January, 2016.
 
January   February
Monarch Butterflies wintering in Mexico   Monarch Butterflies wintering in Mexico
Surviving Cold
Watch the weather! At this coldest time of year, monarchs are at the greatest risk of mortality from deadly winter storms.
  Preparing to Migrate
Monarchs that survive four winter months will mate and begin the journey north in March. Join us for weekly updates on Feb. 4, 2016.
Maps: Report Winter Sightings
Monarch butterfly migration map Monarch butterfly migration map Map of milkweed emergence: Spring 2016
What to Report First Adult
report | map | list
Milkweed
report | map | list
Monarch butterfly migration map Monarch butterfly migration map Monarch butterfly migration map
First Egg
report | map | list
First Larvae
report | map | list
Other Observations
report | map | list
Journal and Activities

What makes the monarch's overwintering habitat in Mexico ideal for survival?

Journal
Next Update February 4, 2016