Moths go with the flow
/SCIENCE SKETCH: a quick look at some new science
Silver Y moths are named for a silvery squiggle that adorns each forewing, like a handwritten y. Twice a year these moths (and a lot of songbirds) migrate northward and southward over Europe while researchers track them with radar.
The question: How do migrating moths and songbirds deal with the wind?
The Appropriately Named Autographa gamma (Wingspan about 1.5 Inches)
The answer: Birds stay in control. Moths go with the flow.
- Moths can't fly as quickly as birds, but they can migrate faster! They wait for a strong wind to start blowing in the right direction, and they hop right on in.
- Birds sacrifice speed for precision to reach their breeding and wintering sites on their own schedule. They press on even in unfavorable winds, and they can adjust for drift.
The upshot: Getting to the right place at the right time is probably more important for birds, and they're strong enough to pull it off. Lightweight little moths can't beat the wind, so they join it.
The caveat: These results don't tell us everything about the wind strategies of insects and birds. We're talking about a single moth species in one part of the world, versus a bunch of songbird species that are all lumped together (since the darn radar can't tell the difference).
See for yourself! Check out the study in the Journal of Animal Ecology.
Bonus material: A Gizmodo story about how these moths navigate using turbulence.
Lastly, L B Loxley's intriguing little film about songbirds and silver Y moths (you're welcome):