Migration in birds

this ppt file is for the knowledge of bird migration

1. MUHAMMD ARSLAN S21-BS-ZFA-1029

2. PRESENTATION. MIGRATION IN BIRDS

3. TABLE OF CONTANT DEFINITION OF BIRD MIGRATION. TYPES OF BIRD MIGRATION. CAUSES OF MIGRATION. ADVANTAGES OF BIRD MIGRATION. DISADVANTAGES OF BIRD MIGRATION .

4. DEFINITION OF BIRD MIGRATION. The word ‘ MIGRATION ’ has come from the Latin word ‘ MIGRARA ’ which means going from ‘ ONE PLACE TO ANOTHER’ ایک جگہ دوسری جگہ‘ ’ M any birds move from on place to another place to obtain ADVANTAGES OF THE FAVOURABLE CONDITION. In bird migration mean two-way journey. Own-ward journey from ‘ HOME ’ to ‘ NEW ’ places & Back journey from the ‘ NEW ’ to ‘ HOME’

5. Definition : According to L. THOMOSON-1926- Bird migration is more or less regular. Extensive movements between their breeding regions and their wintering regions. All birds don’t migrate. The birds which live in northern hemisphere have greatest migratory power. About 70%. ‘Changes of habitat periodically recurring and alternation in direction.’ مسکن کی تبدیلیاں وقفے وقفے سے مکرر اور سمت میں تبدیلی

6. Types of migration in birds . Latitudinal migration. Longitudinal migration. Partial migration. Seasonal migration. Diurnal migration .

7. Latitudinal migration in birds: Movement of animal north to south/ vice versa. Causes a change in climate. Winter are colder as you move North and Warmer as you move south. Example: geese

8. Longitudinal migration . . It is the migration from east to west / vice versa. This is a common type of migration for many birds in Europe. Where geographic features encourage birds to move longitudinally rather than latitudinal. Example: penguins migrate by swimming and cover a considerable distance of a few hundred

9. Partial migration In birds. Those species in which some individuals of a species leave and other stay. Coots and spoon bills ( Platalea ) of our country may be Example: american robins. Average distances cover are about 1000-3000 KM each waya

10. Seasonal migration in birds: Some birds migrates at different seasons of the year for food or breeding. Example cuckoos,swifts,swallows . They migrate from the south to north during summer. These birds call summer visitors. Snow bunting, red wing, shore lark…..migrate from north to south during winter they are called winter visitors.

11. Diurnal migration in birds: Many larger birds like crow , robins, swallows, hawks , jays , blue birds , etc. migrate during day time. These birds are called diurnal birds and generally migrate in flocks. Nocturnal birds : Some small sized of passerine groups like sparrows… etc. migrate in darkness called nocturnal birds. The darkness of the night gives them protection from their enemies.

12. Causes of migration in birds : Most species of birds migrate more or less on schedule and follow the routes in a regular fashion. Gonadal changes . Scarcity of food and day length . Photoperiodism . Seasonal variation . Light.

13. Advantages of birds migration: Animal remain in a favorable temperature. They grow larger. Constant food supply. May lead to the colonization of a new area. Reduces predation and disease from parasites . Greater genetic mixing . Better breeding condition .

14. Disadvantages of birds migration. Many young's are not, able to reach the destination because they die during the course of the continuous and tiresome journey . Storms and hurricanes , strong current of wind, fog are the causes for the death of a sizeable number of migrants . Sometime man made high tours and light houses cause the death of migratory birds . Man themselves are responsible for the death of the migrants. They shoot at these poor birds just for their own leisure amusements .