Reading The Monarch Migration Content Geography/Science by Melanie Ann Appel Reading Strategy Analyze Cause-Effect Relationships What causes the butterflies to be unable to fly? It’s fall, and millions of monarch butterflies are migrating to warmer climates for the winter—heading either to the California coast or to certain mountains in Mexico Monarch butterflies know fall is here the same way that we do; they feel the chill in the air While we adapt by putting on a sweater, the situation is much more serious for the monarchs Temperatures below 55°F make it impossible for them to fly; temperatures below 40°F paralyze them The monarchs originated in the tropics and can’t live for long at temperatures below freezing chill a cold temperature, but not freezing paralyze not able to move tropics a very hot region of the earth 20 Unit • Chapter At the same time that the air is cooling, the nectar supply that feeds the butterflies is dwindling To survive, the insects begin migrating in late summer, flying with the wind to reach their winter homes Up to 100 million monarch butterflies migrate either to California or to Mexico each year (This isn’t the entire population.) There are more than 25 winter roosting sites in the Sierra Madre Oriental Mountains of Mexico In both regions, butterflies depend upon trees for their survival The insects cluster in pine and eucalyptus trees along the California coast and in ovamel trees in Mexico Reading Strategy Analyze Cause-Effect Relationships What are the causes of the monarch migration? Monarch butterfly getting nectar from milkweed ✓ Reading Check Recall details Where the monarch butterflies migrate to in the fall? Monarch butterflies clustered in an ovamel tree dwindling becoming smaller in number roosting resting or sleeping cluster bring or come into a tight grouping Recall details What helps the butterflies reach their winter homes? Make inferences How the butterflies know it is time to go on their journey? Unit • Chapter 21 Build Your Knowledge The information in a reading is sometimes presented in time, or chronological order Events are presented in the order in which they happened Look at paragraphs and Which season does the author describe? Which seasons does the author describe in paragraphs and 6? Is this reading presented in time order? Monarch butterflies creating a shingle effect Wintering monarchs cluster together The end result looks like massive clumps of feathery orange-and-black grapes Each butterfly hangs with its wings over the butterfly beneath it, creating a shingle effect that buffers the bugs from the rain and creates warmth The weight of the cluster also prevents the butterflies from being blown away Butterflies stay in their winter homes until about March, when they begin a quick retreat to their summer homes, at times traveling as fast as 30 miles per hour Reading Strategy Analyze Cause-Effect Relationships The butterflies cluster together The cluster has three effects What are they? massive huge clumps groups or masses shingle something that overlaps something else buffers protects or keeps safe retreat a move back 22 Unit • Chapter ... are the causes of the monarch migration? Monarch butterfly getting nectar from milkweed ✓ Reading Check Recall details Where the monarch butterflies migrate to in the fall? Monarch butterflies... describe in paragraphs and 6? Is this reading presented in time order? Monarch butterflies creating a shingle effect Wintering monarchs cluster together The end result looks like massive clumps of... begin migrating in late summer, flying with the wind to reach their winter homes Up to 100 million monarch butterflies migrate either to California or to Mexico each year (This isn’t the entire population.)