the Way of the Turtle

Magnificent Monarchs
Wednesday, September 28, 2011

Monarch butterflies, that is.

Over the last few weeks I've freqently seen solitary monarch butterflies fluttering around, which has me wondering - why now? So I did a little research and learned a bit more about these beautiful, fascinating insects.

The monarchs that I've been seeing recently are probably the 4th generation this year, having been born about a month ago, though it's also possible they're 3rd generation looking to mate and lay eggs to produce the 4th generation. Turns out that each year the 4th generation monarchs migrate south to Mexico (about 2500 miles - incredible!) to spend the winter in a warmer climate, then early in the year they mate and head back north to lay their eggs in the southern USA. These eggs hatch into caterpillars which eventually metamorphosize into 2nd generation adults, who repeat the process to produce 3rd generation adults, spreading over the summer into the northern US - and then the process repeats again in the late summer/early fall, producing 4th generation adults that end up migrating to the same locations their great-grandparents did to spend the winter (no one understands how they know where to go back to each winter, given that they're several generations removed from the adults that migrated the previous winter.) It's also not clear if we understand why the spring and summer generations only live for about a month, while the generation that migrates lasts approximately eight months.

For more info, I recommend the Monarch Butterfly website and Monarch Watch. A google search will also reveal many sites about these fascinating and lovely orange and black butterflies.

So it seems like the monarchs I've been seeing are either 3rd generation adults looking to procreate and produce the 4th, migratory generation, or they are part of the migratory generation themselves. Regardless they are incredible to watch and I always pause when I see one go by, especially if there's an opportunity to get a photo.

The thought of these tiny, fragile-looking butterflies flying 2500 miles or more to reach winter roosts boggles the mind. Just amazing.

Unfortunately, like so many wild creatures, monarchs are on the decline due in a major part to loss of habitat both here and in Mexico. The migrating population this year is among the lowest ever, and drought conditions in the south are causing higher than normal mortality rates. Monarch Watch has some excellent articles on monarch conservation, including suggestions as to what can be done to encourage the population of monarchs to recover.

JMH