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How do albatrosses find their way?. Question Albatrosses usually breed on small islands and spend much time flying over open ocean in search for food.

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Presentation on theme: "How do albatrosses find their way?. Question Albatrosses usually breed on small islands and spend much time flying over open ocean in search for food."— Presentation transcript:

1 How do albatrosses find their way?

2 Question Albatrosses usually breed on small islands and spend much time flying over open ocean in search for food. During breeding, albatrosses have to come to their nests to feed nestlings. Open ocean does not have landmarks that could be used for orientation. The question is how do albatrosses find their way in the open ocean and find their way back to the nests?

3 Different types of orientation in animals

4 Compass orientation Many animals species use compass orientation in which they “know” the direction they should move. Animals may use sun, stars, and magnetic field to determine their direction.

5 Dead Reckoning Some animals use dead reckoning: they memorize the direction and distance of their travel from the initial point and then use this information to find their way back

6 True Navigation Some animals are capable of “true” navigation: they are aware of their location irrespective of how they got there and they are also aware of their goal location. With this information, animals can determine where they should go.

7 Which type is likely used by albatrosses?

8 It is unlikely that albatrosses use simple compass orientation or dead reckoning because their travel is usually not in a straight line and it covers tremendous distance. Dead reckoning still might be possible. True navigation is most likely.

9 Landmarks are out because ocean does not have landmarks. Albatrosses can use sun, magnetic field or chemical cues for their navigation.

10 Bonadonna et al. (2005) placed magnets on albatrosses heads which interfered with magnetic field and then used satellite telemetry to investigate whether such procedure affected navigational abilities of albatrosses.

11 Distorted magnetic field did not appear to affect albatrosses’ ability to find their way home.

12

13 Magnetic field alone is unlikely to be the main navigational mechanism in albatrosses. This study does not rule out that magnetic field is used as it is possible that these birds use multiple mechanisms for orientation. Experimental albatrosses had their vision and chemoreception unaltered, so they could have used either one.

14 Can albatrosses use chemical signals for orientation?

15 Nevitt & Bonadonna (2005) demonstrated that procellariformes (including albatrosses) respond to familiar smell by elevating their heart rate in laboratory conditions.

16 Procellariforms also orient toward familiar scents in a Y- maze.

17 Albatrosses are capable of discriminating rather weak odors associated with ocean. They might be able to use their sense of smell for orientation.

18 New experiments are necessary to establish whether albatrosses: Use visual information (sun) for orientation. Use magnetic field for orientation. Use sense of smell for orientation.

19 Experimental design Some birds will be fitted with frosted goggles so that they will not be able to see location of the sun. Some of these birds will also be fitted with magnets to interfere with magnetic field. Some of these birds and some new birds will have their nasal cavities clogged so they would not be able to smell. All birds will be released away from their home islands and we will trace their location with satellite telemetry to investigate whether these treatments would interfere with their navigation.

20 Potential outcomes Birds with frosted goggles but without magnets will find their way home – would support the idea that they use magnetic field. Birds with frosted goggles and with magnets will find their way hope – would support the idea that they use something else for orientation. Birds with frosted goggles, magnets and clogged nasal cavities will be disoriented – would support the idea that either one of the three mechanisms are necessary for orientation. Birds with nasal cavities clogged but without magnets and without goggles will be disoriented – support the idea that albatrosses use olfaction for navigation.


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