Monarch Butterfly

The monarch butterfly may be the most widely recognized of all American butterflies with its distinct orange, black, and white wings. While beautiful, this coloring actually sends a warning to predators that the monarch is foul tasting and poisonous. Found throughout the United States, as well as Mexico and Canada, one of the most notable characteristics about the monarch is the astonishing 3000 mile journey some will make in the fall to their wintering grounds in the Sierra Nevada Mountains of Mexico or to southern California, depending on which part of the United States or Canada they migrate. Diet In their larval stage monarch caterpillars feed almost exclusively on milkweed and as adults get their nutrients from the nectar of flowers. The monarch will always return to areas rich in milkweed to lay their eggs upon the plant. The milkweed they feed on as a caterpillar is actually a poisonous toxin and is stored in their bodies. This is what makes the monarch butterfly taste so terrible to predators. Population Millions of monarch butterflies make the trip down to Mexico to roost for the winter. During the migration tens of thousands will land on a single tree in certain areas along their migratory path. Range Monarchs can travel between 50 - 100 miles a day; it can take up to two months to complete their journey to winter habitats. Wherever there is milkweed there will be Monarch butterflies. The monarch is widely distributed across North America, from Central America northwards to southern Canada, and from the Atlantic to the Pacific coasts. Three geographically distinct populations make up the total North American range of the species, one each both east and west of the Rocky Mountains, and one Central American. Each of these populations has a distinct migratory pattern. Monarchs that live west of the Rocky Mountains will migrate to southern California for winter while monarchs that live east of the Rockies will migrate to Mexico. Behavior Monarchs can produce four generations during one summer. The first three generations will have life spans from 2 - 6 weeks and will continue moving north. During this time they will mate and have the next generation that will continue the northward migration. The fourth generation is different and can live up to nine months. These are the butterflies that will migrate south for winter to either Mexico or southern California. Threats to Monarch Butterflies It is predicted that one of the many effects of climate change will be wetter and colder winters. If they are dry, monarchs can survive below freezing temperatures, but if they get wet and the temperature drops they will freeze to death. Because hundreds of millions of monarchs are located in such a small area in the Sierra Nevada of Mexico during the winter, a cold snap there could be devastating. http://www.defenders.org/monarch-butterfly/basic-facts