New Monarch Butterfly Studies May Provide Reasons for Optimism

[mike_c]

New Monarch Butterfly Studies May Provide Reasons for Optimism

August 5, 2015 by Entomology Today

Seven new articles on monarch butterflies were published today in the Annals of the Entomological Society of America.

“This group of papers is intended to give us the latest and best data available on the status of monarch populations and perhaps point the way to our best efforts to protect them,” said Lawrence E. Hurd, editor-in-chief of the journal.

Unlike many past studies that relied on monarch populations in Mexico, where they overwinter, the authors of these studies observed monarch populations in Canada, Michigan, Pennsylvania, and other U.S. states. Results vary, but some studies found no significant declines of monarch populations in their summer breeding areas.

“I think we’ve really been focused too much on Mexico,” University of Georgia ecologist Andy Davis, a co-author of one of the papers, told the Washington Post. “If you were charged with figuring out how many people are participating in the Boston Marathon each year, you wouldn’t count the number of people who cross the finish line. But for many years we’ve been counting the finishing monarchs in Mexico. We’ve been doing it backwards.”

more@link: http://entomologytoday.org/2015/08/05/new-monarch-butterfly-studies-may-provide-reasons-for-optimism/

[Brother Buzz]

1. The population had a slight uptick in California's wintering grounds....

But way, way down from what they were in the fifties and sixties.

[mike_c]

2. I wonder whether the overwintering migratory populations might simply be...

...an evolutionary hedge against population decline in the breeding range, rather than the main trunk for ongoing population maintenance.

[Brother Buzz]

3. There is an element of adjust and adapt

I always found it interesting, monarch butterflies winter in Mexico, high in the mountains, yet the California population winter at sea level.

[mike_c]

4. both locations share cool temperatures with low probability of hard frost

Of course, lots of other potential overwintering sites have similar conditions. That's another reason why I wonder whether the overwintering migratory population might only be a small subset of the breeding population. I mean, we know that the migratory population is a subset, but it's never been clear whether that subset is simply the tough ones that complete the migration or whether migratory overwintering is just one behavioral phenotype among others. If the latter, then unstable overwintering populations might not say much at all about the breeding populations.

[cherokeeprogressive]

5. We had a ton of 'em this spring in the San Bernardino National Forest.

Some days I'd see 30-40 at a time.

[KittyWampus]

6. They don't mass here in the numbers they used to.

But I'm glad if they are strong in other areas.

[UTUSN]

7. R#3 & k n/t