Journey North: Monarch Butterfly

Not All Monarchs Make it to Mexico
What Do Florida Tagging Results Suggest?

Only 3 of Mr. RuBino's 12,500 tagged monarchs have been recovered in Mexico. He said this recovery rate is very, very low. Overall, an average of one in 100 tagged monarchs is recovered in Mexico (which is 1%.)

If Mr. RuBino’s monarchs had been recovered at the average rate (1%, or 1 in every 100), how many recoveries would you expect?

Where Do Monarchs Tagged on the Florida Coast in Fall Go?

The Answer
Mr. RuBino would expect 125 recoveries in Mexico! So why has he only had three? What happens to monarchs once they reach the Florida coast? We plotted his tag recoveries on this map. Mr. RuBino describes what he’s learned:

"I know for certain that, in the fall, monarchs passing through this area spread fairly equally to the west and southeast. We've had a few recoveries along the Gulf coast to the west of us, and some recoveries southeast of us, down the peninsula. Since only 3 of the almost 12,500 monarchs tagged at St. Marks since 1988 made it to Mexico, I fear that most of them end up in the middle of the Gulf of Mexico."

The Importance of Negative Data
Lessons Learned from Mr. RuBino
By the way, this research shows how important it is to collect negative data. Mr. RuBino kept tagging monarchs even though his results were negative (no tag recoveries). Look how many years it took to tag 12,500 butterflies! Surely he must have been discouraged at times, but he didn’t give up. As you look at the map showing his tag recoveries, think about what his perseverance has shown us about monarch migration! What did you learn? What new questions do his data raise?