Welcome to the blog for Thomas Parry Photography. My purpose is to inform the public about photographic projects I have recently completed as well as those in progress and planned for the future. I will periodically post articles about different aspects of photographing nature, people and places. As I work with new hardware and software tools, I will pass along lessons learned that may aid other photographers. I will periodically write reviews about photographic equipment with which I have experience and books I read that may be helpful to others. I hope you enjoy reading my blog and return frequently. I invite your thoughts, good ideas, opinions and feedback.
| 08 December, 2013 13:56
Every year, beginning in October and lasting through December, tens of thousands of North American Monarch Butterflies migrate more than 2,500 miles south to escape the extreme cold of winter in the northern and central states and Canadian provinces. Monarch Butterflies are the only insect known to make such a lengthy and challenging migration each year. Monarchs from states east of the Rocky Mountains will migrate deep into Mexico and overwinter in Oyamel Fir trees. Monarchs west of the Rockies migrate to the Eucalyptus tree groves of the central and southern California coastline. It is in these locations that Monarchs will hibernate December through February.
In March and April, the hibernating butterflies come out of hibernation to find a mate. They then begin the migration back to northern climes as temperatures warm up in search of milkweed plants upon which to lay their eggs. This process starts the first of what will be four generations of Monarchs that will live throughout the year. The eggs hatch in about four days into caterpillars. For about two weeks the caterpillars will eat the milkweed and be fully-grown at which time they will attach themselves to a stem or a leaf and transform into a chrysalis. Within the chrysalis, the body parts of the caterpillar undergo a metamorphosis into a beautiful butterfly. Once the butterfly emerges, it will fly away and feed on flower nectar. Unfortunately, this generation of Monarchs will only live for about two to six weeks. They will mate, lay their eggs and generation number two begins its lifecycle.
The second generation of Monarch Butterflies is born in May and June and the third generation is born in July and August. These butterflies will go through the exact same life cycle as the first generation dying in two to six weeks after becoming a beautiful Monarch.
Interestingly, the fourth generation of Monarch Butterflies is different than the first three generations. The fourth generation is born in September and October and goes through exactly the same process as the first, second and third generations except for one part. The fourth generation of Monarchs does not die after two to six weeks. Instead, this is the migratory generation that will journey to the warmer climates of Mexico and California for the winter and will live for six to eight months until it is time to start the whole process over again.
Between November and January this year, I traveled to several Monarch overwintering sites on California’s central coast including Pacific Grove, Pismo Beach and Natural Bridges State Park in Santa Cruz. I was gratified to find the quantity of overwintering Monarchs to be substantially higher than what I’ve observed over the last two years. Two factors adversely impacting Monarch migratory patterns and numbers are eradication of milkweed by farmers and destruction of the trees in which they hibernate each winter. Milkweed is essential for the caterpillars to develop. Without it they cannot survive. Also, Monarchs instinctually return to the same trees each year. No one knows how or why this happens given that each year a different generation of butterflies completes the long migration.
To me, these butterflies are a wonder and miracle of nature. What is most amazing about the life cycle of the Monarchs is how the four generations of butterflies works out so that the Monarch population can continue to live on throughout the years, but not become overpopulated.