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Science Dept.

Biology BIO 100
Migration

1. Behavior Helps the Organism to Survive and Adapt to its Environment

2. Some Aspects of Migration
   1. The Northern Cliff Swallows Reappear at the Mission of San Juan Capistrano in Southern California within a Week of March 19, the Feast of St. Joseph. At the Mission these Swallows Build Vase-shaped Mud Nests, Mate and Rear their Young. About the Middle of September, they Leave their Nesting Territories and Fly Southward to Winter in Brazil

   2. The Monarch Butterflies Settle in the Trees of Monterey, California within a Few Days of Mid October

   3. Job (39:26) "Doth the Hawk Fly by Thy Wisdom, and Stretch Her Wings South?"

   4. Jeremiah (8:7) "Yea, the Stork in the Heaven Knowth Her Appointed Times; and the Turtle and the Crane and the Swallow Observe the Time of their Coming."

3. Why the First Bird Fossil?
   1. Archaeopteryx from the Jurassic Period
      1. Thought at First to Be a Reptile
         
      2. Today, Amid Controversy, Some Experts Think Archaeopteryx Was a Bird

   2. Archaeopteryx in Stone
      1. Found in the Solenhofen Limestone, a Fine-grained, Clastic, Marine Limestone. The Ancient Sediment's Texture Is Fine Enough to Show the Detail of the Feathers
         
      2. Was this Creature Gliding or Flying over Open Water?

   3. Archaeopteryx Feathers
      1. Some of the Wing Feathers of Archaeopteryx Are Aymmetrical
         
      2. In Today's Birds, Asymmetrical (about the Vane) Wing Feathers Are Used for Powered Flight

   4. Migration?
      1. Many Birds Migrate, and Some Have Flight Paths Over Open Water. Some of these Species Can be Found in the Stomach Contents of Species of Ocean Fish

      2. What was Archaeopteryx Doing Over Marine Waters?
         1. Carried by River Current then Wind and Waves After Dying on Land?
            
         2. Just a Short Flight Over Open Water?
            
         3. Blown Off Course By Storms?
            
         4. Long Distance Migration?

4. Why Migrate
   1. Food

   2. Warm Habitat for Raising Young

5. Who would Tend to Disperse

6. What May Have Caused Migration
   1. Advent of Glaciation

   2. Territorial Dispersion

   3. Other Factors

7. How Do Birds Get Ready for Migration
   1. External Stimuli

   2. Photoperiodism

   3. Hormones

   4. Some Examples

8. Migration by Day or Night
   1. Some Day Migrators
      1. Hawks and Other Birds of Prey Like to Use Thermals which Occur during the Day. They also Stick to Narrow Routes such as Along Mountainsides, for Example the Zip Zag Ridges of Pennsylvania. This Would Be a Good Example of the Geology Playing a Role in Bird Migration.

      2. Redwing (a Thrush)

      3. European Swallows

      4. Red-winged Blackbirds

      5. Chimney Swifts

   2. Some Night Migrators
      1. Warblers, for Example the Black and White Warbler

      2. Blue Grosbeaks

      3. Rose Breasted Grosbeaks

      4. Indigo Buntings

      5. Water Fowl

      6. Shorebirds

9. Orientation
   1. Summary
      1. Visual Cues

      2. Infrared Sensitivity Including Day Clock

      3. Ultraviolet Light Including Day Clock

      4. Sun Compass Including Day Clock

      5. Polarized Light Including Day Clock

      6. Star Compass

      7. Magnetic Cues

      8. Smell

      9. Weather

      10. Low Frequency Sound

      11. Rotational Force of the Turning Earth (?)

   2. Orientation by Visual Cues
      1. Humans Can See 100 Miles at "Bird Altitude"

      2. Birds Ability to Pick Up Differences Are 2 to 3 Times Greater than People (Sometimes 7 Times)

      3. It Is Believed that Visual Cues Are Used when Near Home Territory

      4. Can Not Be Used by New Birds - They Have Never Been Over the Territory

      5. Can Not Be Used by Birds Migrating Over Open Water

   3. Orientation by Sun Position

   4. Orientation by Stars - Polaris

   5. Orientation by Magnetic

   6. Orientation by Smell

   7. Orientation by Weather - Some Birds Movements Coincide with Weather Conditions
      1. Southward Migrations in Fall Appear to Be Timed after the Passage of a Cold Front with a Flow of Continental Polar Air Coming in from a Northerly Direction and Moving to the South

      2. Northward Migrations in Spring Appear to Be Timed with a Warm Front, with Barometric Pressure Dropping, and Warm Moist Air Moving to the North from the Gulf of Mexico and Carribean

10. Some Case Histories

11. Flyways