Movement Ecology

Question 1

Movement

Answer 1

Changing of the spatial position of an individual

Properties of movement:

• active or passive
• happen on different spatial and temporal scales
• local (habitat use) or looking for new habitats (migration)

Question 2

Reasons for movement

Answer 2

Plants: pollinations, seed dispersal
Animals: search for new suitable habitat, search for food or mating partners, escape from predators…

Question 3

Influencing factors of movements

Answer 3

Navigation capacity, motion capacity, internal state, external factors

Question 4

Bewegungsarten

Answer 4

Random walk, levy walk, levy flight (Many short movements. Few, rare very long ones.)

Question 5

Navigation

Answer 5

Moon compass, star compass, magnetic compass, path integration, bird migration: genetically controlled.

Question 6

Isoline

Answer 6

along line magnetic intensity does not change. Some isolines of low and high field intensities.

Question 7

Magnetic navigation in birds

Answer 7

• Radical-pair mechanism: Compass in the eye. Cells in retina are parallel. Depending on how the magnetic field lines align with these cells, birds see a shadow of the field lines. They can see inclination and direction. Additionally they have to remember where they are. They create a map from memory.
• Magnetite mechanism: birds have supermagnetite crystals in the upper beak that senses diff in magn. intensity. Neuronal pathways associated with magnetite-based receptors

Question 8

Dispersal / philopatry

Answer 8

• populations in discrete subunits
• exchange between subunits
  –> dispersal: natal dispersal (from birth region), secondary dispersal
  stay in place of birth: philopatry
• genetic diversity between subunits

Question 9

Advantages of philopatry

Answer 9

• familiar region (food, shelter, resting places)
• larger birthing group (Verdünnungseffekt, verwirrungseffekt, räuberentdeckung, geteilte wachsamkeit, räuberabwehr, nahrungssuche, resourcenverteidigung, informationstransfer, energiesparen)
• inheritance of parent territory

Question 10

Advantages and disadvantages of dispersal

Answer 10

Disadvantages: energy loss, unfamiliar territory, predators, time lag to good health condition
Advantages: avoidance of aggression, avoidance of inbreeding (choice of dispersal often linked to sex: often only males disperse, that way inbreeding is avoided)

Question 11

Migration of grey whales

Answer 11

cyclic, seasonal, daily

Summer: ice free, nutrient rich arctic waters
Winter: warm waters, homing, mating

Question 12

Mobility of species

Answer 12

• Mobile Organismen 
– General
• Dispersal, migration, movement, gene flow 
– Bewegungsarten 
• Foraging, migration, dispersal, home range, homing, nomadism 
• Sessile Organismen 
– Ausbreitungsstadien 
• Abiotische Faktoren: Wind 
• Biotische Vektoren