I read the following article with great interest “Butterflies fly using efficient propulsive clap mechanism owing to flexible wings”.
Subsequent reports have come out with headlines such as “Butterfly wing claps explain mystery of flight” and“Natural wonder: Wing ‘clap’ solves mystery of butterfly flight”
Butterfly wings come in all shapes, sizes, and degree of flexibility. They have evolved with a range of mechanisms and strategies in flight. Butterflies such as the Silver-washed Fritillary (see video below) and Yellow Sulphur clap their wings frequently, but other butterflies, the Monarch Butterfly for example, does not “clap” their wings every time they take flight. The Monarch’s wings create an open cup shape, operating in more of a figure eight pattern.
Scientist have known about butterfly wing clapping for more than fifty years. I don’t think a mystery has been solved by the recent study from Sweden’s Lund University nonetheless, the articles are interesting to read.
In the above video you can see in the first few frames when the Monarch is taking off that its wings do not clap.
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On a more terrifying note, the Western Monarch population has become nearly entirely extirpated from its historic range. A recently published article from the Xerces Society “Western Monarch Population Closer to Extinction as the Wait Continues for Monarchs’ Protection Under the Endangered Species Act”reports a 99.9 percent decrease in population since the 1980s. Only 1,914 Monarchs were located during the annual Thanksgiving Butterfly Count.
Monarchs at the Goleta Butterfly Grove, 2015
In 2015, when my daughter Liv was living in Santa Monica, she and I took a day trip to the Goleta Butterfly Grove, just outside of Santa Barbara.
Goleta Butterfly Grove
The butterflies were, for the most part, sleeping quietly in the Eucalyptus trees. A few were fluttering about, drinking nectar from the Cape Honeysuckle (Tecoma capensis) growing nearby.
Non-native nectar source for Monarchs, Cape Honeysuckle
The Western Monarch Butterfly demise has been in the making for decades. The Ecaplytus trees the butterflies were roosting in appeared stressed. Eucalyptus trees are not native to California and are highly flammable. I wondered at the time why the forest couldn’t be underplanted with native tree and also wondered exactly what were the trees the butterflies may have historically roosted in.
With unbridled development that has lead to loss of habitat, forest fires, a warming climate, and the use of deadly pesticides and herbicides in this American breadbasket to the world, is it really a mystery as to why the butterflies are nearly extirpated from California.
Western Monarch Thanksgiving Count Data 1997-2020 shows that despite a strong volunteer effort, monarch numbers are at the lowest point recorded since the count started in 1997.