Monarch Butterfly News: July, 2013
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Your Sightings!
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With low numbers and a late migration, many people are still waiting to see their first monarch of the year. Tracking continues!

This Month's News:

Image of the Week
Monarch Butterfly laying egg on milkweed
Breeding Season
News: Where Are the Monarchs?
Monarchs are scarce this summer across their breeding range because of two key factors:

1. Record Low Last Winter
There were only 60 million monarchs wintering in Mexico last winter, 80% below the 350 million monarch average. The area of forest covered with monarchs was only 3 acres, compared to the 17-acre average. Why so few? Drought and excessive heat during summer 2012 resulted in low reproduction last year.

2. Cold Spring, Slow Migration
This spring's unusually cold temperatures across the middle section of the country delayed the migration northward. The season's first monarch generation was slow to develop in the southern U.S. and late to migrate northward.

What's Happening Now?
Low numbers, cold temperatures, and slow spring migration meant few monarchs across the north in June. Monarchs must have a productive breeding season this summer for the population to recover.

Summer Breeding
During the breeding season, monarchs can produce a new generation in about 30 days, resulting in four generations. The monarchs that migrate to Mexico this fall will be the great-great-grandchildren of those who left Mexico last spring.

A Missing Generation?
By arriving late this spring across their breeding range, monarchs may not have time to complete four generations. This could result in a small fall migration and low numbers in Mexico again next winter. However, monarchs have a high reproductive potential and they breed across a large region. Breeding success in one area can counteract the effects of poor conditions in another.

Monarch Butterfly in Texas
Record Low Last Winter
Monarch Butterfly Development Time: Life Cycle Timing
Cold Spring
Monarch Butterfly egg

Monarch Egg
Image: Holli Hearn

Monarch Butterfly eggs in New Jersey
Annual Cycle
Fall Tracking Begins in August
It's hard to believe, but fall migration begins next month! On August 1st, we open the "Journey South" database for fall sightings. When you see a monarch—nectaring, flying, roosting, or breeding—we want to know about it.

What to Report to Track Fall Migration
Next Update August 1, 2013