We stopped by the Monarch butterfly grove in Pismo Beach. They claim that there were 22,000 butterflies there today. I wonder how they know....Here's what they say about the butterflies: "Monarch Butterflies begin to appear along the California Coast early in October, when the first chill of fall, and a decline in nectar signal the need to migrate to the south to escape the killing cold of northern winters. The Butterflies may travel over the Sierras and west of the Rockies as far away as Canada to seek protection here in the groves of Monterey Pine and Eucalyptus that offer shelter from the wind and a foliage that the Butterflies can clasp with their sharp tarsal claws.
The Butterflies will form dense clusters on the trees, each animal hanging with its wing down over the one below it to form a shingle effect, that gives shelter from the rain and warmth for the group. The weight of the clusters helps keep it from whipping in the wind and dislodging the Butterflies. If a Butterfly is dislodged it may fall victim to insects or field mice, since it cannot fly at temperatures much lower than 55 degrees, and at a temperature lower than 40 degrees, it is unable to move at all.
On warm, calm winter days, the Monarchs leave their cluster to search for flower nectar of about 90% water and 10% sugar. When the day cools the Butterflies again cluster, but not necessarily in the same groupings.
The Monarch remains in the more protected areas along California's coast in February, when warmer days of spring herald the north-easterly migration. The flight south is leisurely, but the return journey is swift; the Monarch's wings, beating rapidly through a 120 degree arc, propel them at speeds of up to 30 miles per hour.
After mating, the females seek out the milkweed plant. This plant plays a crucial role in the life cycle of the Monarch, for it is only upon the milkweed that the female will deposit her eggs. The eggs are multi-faceted creamy, yellow spheres, the size of the head of a pin; they have been described as "priceless gems cut by a master craftsman." Within three or four days, depending on the temperature, the eggs turn a dark gray and very hungry larvae eat their way out of the casings. Each larvae, or caterpillar, eats milkweed non-stop for the next fifteen days, and its weight increases 2,700 times. By the 5th day of its life, the caterpillar has outgrown its skin and must shed it, or molt, in order to grow. The animal has to go through this process three more times before it reaches maturity.
Around the fifteenth day, the caterpillar feels a sense of urgency, It's skin is beginning to harden and internal changes are taking place; the miracles of metamorphosis is about to begin, and it is on a timetable. It must find a suitable protected place above the ground, before its hardening skin makes movement impossible.
Having found such a spot, the caterpillar lays down a mat of silk fibers, attaches itself upside down to the mar, curls its body into the shape of a letter "J" and sheds its skin one last time to replace it with a shell covering. During the next nine to fifteen days, extraordinary changes take place within this chrysalis; the leaf chewing caterpillar that disappeared into it emerges as a radiant, nectar-sipping Monarch Butterfly.
Clinging to the chrysalis, the animal pumps body fluid into its limp and useless wings, expanding them to 60 times in size. The new adult Monarch must spend several hours basking in the sun, hardening its wings and getting its body functioning, before it is ready to fly away.
Several generations of Monarchs will be born during the migration; but those that leave in March will never return. Monarch Butterflies have an average life span of about 6 weeks long, except during the winter when monarch can live for about six months.
So the cycle continues, north to south and back again, from egg to caterpillar to Butterfly, the elegant animals with the velvet wings going about the urgent business of living."
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