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Insect Migration

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Table 10.2 Migration

Piloting by

1. Visual Landmarks: Mountains, Forest, deserts, Sea and Sea coast, Rivers, Large lakes, High

ways. Diurnal fliers make use of mountain ranges, long rivers and high ways for prolonged long

distance flight

2.Celestial and astronomical bodies:

a. Sun and sunlight (VIBGYOR-visible spectrum)—Sun as a compass

b. Bright star pattern and planetarium Experiments

c. Moon orientation- In Arctic region sunlight is continuous and magnetic directions are not clear

d. Rotation of polarised light along with the sun reveals North direction on a partially cloudy day

3. Geomagnetism: Cellular Fe3O4 particles respond as Magnetic Radical pair-reaction

mechanism for Magneto-reception (RPRM) has been discussed in last chapter

4. Meteorological and Geophysical conditions: Atmosphere and weather features

5. Sense Organs: Eye, Ear (Ultra sound in Bats), Nose, Sensory hair. Light consists of Infra and

Electro Magnetic Vibrations (EMV), VIBGYOR, UV and IR. Visible spectrum λ and νh

6. Optical flow: Horizon, height and velocity

7. Circadian rhythms: Hormonal (Physiological)

8. Wind speed and its direction

9. Memory and Brain

10. Genetic Programming (Inherited Navigation Capacity)

11. Aerodynamic Formations

12. Endurance during Migration flight: (L/ D ratio is usually high)

Long distance migration is found in some Insects, Aquatic animals, birds and mammals

* Information from varied sources is compiled

1.

Schistocerca gregaria—“migratory locusts” long distance (4500 km) flier.

2.

Monarch Butterfly—long distance flyer from Canada to Mexico (3500 kms).

3.

Lady bird beetles—the predators of aphids—carried by updrafts-odour helps in

migration.

4.

Aphids—carried by wind and (attracted by light) some are sedentary.

5.

Honeybees and Ants are known for homing instinct, communication and

navigation. Honeybees recognize and use landmarks for flight.

6.

Ants are known for their homing ability. Ants use the Sun as a compass. Ants

and bees have a “Map sense”. Desert ants are known for path integration.

7.

Owlet moth (Noctuid)—Migrates from Europe to Mediterranean and breeds

along the migratory route. They also make use of earth’s magnetic field.

8.

Dragon fly migrate 100–1000 kms. Returning dragonflies come from different

generations.

9.

Many species of butterflies in Southern India migrate before monsoon.

References

1. Shamoun-Baranes, J., & van Gasteren, H. (2011). Atmospheric conditions facilitate mass

migration events across the North Sea. Animal Behaviour, 81(4), 691–704.