The fate of the monarch butterfly is secure in the subtropics, but the phenomenon of the migration is threatened. The monarch is only able to lay its eggs on milkweed, considered by many to be a "trash plant." With the filling in of the wetlands in North America and the clearing of milkweed from roadsides, the habitat loss to monarchs is significant. The logging of buffer zones around the sanctuaries in Mexico and the need for the natives to sustain a living, historically from lumber, challenges the protection of the overwintering habitat.
The last Ice Age pushed milkweed up north and the butterflies followed. The phenomena of the migration may not continue beyond the next 15 to 20 years, according to several researchers. Hidden Oaks is part of a tri-national organization, Monarch Watch, based at the University of Kansas, to track monarch migrations in the hope of learning routes as well as dynamics that affect successful monarch migration.
The techniques used to track butterflies have been improved to lesson the risk to the fragile monarch. Self-adhesive, numbered tags are attached to a specific cell in the hind wing. After taking notes on characteristics of the butterfly, the monarch is released back onto the flower from which it was gathered. Last year over 50,000 monarchs were tagged in the United States and Canada. Only 82 were located in Mexico, 194 were recovered in route, as reported to date.
Questions are still pondered as to whether the East Coast monarchs journey to yet another locale. The monarchs west of the Rockies overwinter in southern California and Baja, Mexico. Could ours have taken a hiatus in the Caribbean? In recent years, monarchs tagged in Maryland and Virginia have been found in the Mexican sanctuaries 80 miles northwest of Mexico City. There is still a lot to learn. Staff members from Hidden Oaks conduct programs on tagging at the center as well as Green Spring Gardens Park.
Also at Hidden Oaks, raising monarchs attained through Monarch Watch, the naturalists are creating a habitat to encourage the second-to-last generation to mate and lay eggs. They hope this final generation will mature, be tagged and then be released for their migration. Recent studies have indicated that captive reared monarchs have no disadvantage during migration.
There are a number of butterfly-tagging programs at the park sites this year. Call your local nature center to help out and follow the metamorphosis, as the tiny caterpillar becomes an eating machine, then a beautiful gold-flecked jade chrysalis and finally, a majestic butterfly.
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