"It is a mystery," says monarch scientist Dr. Bill Calvert.
Here are some of the factors he considered when thinking about the question:
- Milkweed does grows in the Bahamas, so it's possible that some islands have a monarch population of their own.
- Some observers have reported monarchs appearing for a few weeks in the fall, and then disappearing until the next fall.
- One monarch that was tagged in New Jersey was recovered in the Bahamas. (One monarch tagged in Ontario was recovered in Cuba, too.)
- In the case of these 200 monarchs, it seems likely they were blown in.
- What was the weather like leading up to this observation? Is the timing correct?
Image: Tim Higgs