1. Habitat Selection

2. Habitat Selection?

3. Some Terms… Habitat – Place where an organism lives
Home Range – Area that an organism occupies during its life
Territory – An area occupied and defended by an organism
Migration – The long distance movement, and subsequent return, from one location to another.

4. Why choose a certain habitat?
Why do you live where you do?

5. Why do animals choose a certain habitat?
Genetics vs. Early Experience

6. Why do animals choose a certain habitat?
Food
Ideal Free Distribution (Manfred Milinski)

7. Genetics and Early Experience
Males and Females raised on Cellulose or Cedar bedding
Males generally prefer what they are raised on.
Females generally prefer cedar by at least the third day.
Older females switch to cedar faster than younger females.
Males influenced by early experience whereas females are more influenced by genetics.

8. How do animals pick a habitat: Genetics and Early Experience

9. Factors: Early Experience

10. Foraging Behavior
Barn Owl
What to eat?

11. More on Patch Ecology
Risk-Sensitive – Animals that can tell one patch from another patch
Risk-Prone: Animals willing to take risk
Risk-Averse: Animals not willing to take the risk

12. Changes in the strategy: Are animals risky or safe?
“Risk Prone” willing to take risks
“Risk-averse” avoid risk and will take the safer option.

13. Changes in the strategy: Caraco et. al. and Yellow-Eyed Juncos
Birds choose 1) variable (0 to 6 seeds) or 2) constant (3 seeds)
Done at 1°C and 19°C.
Birds are risk-averse at 19°C, risk-prone at 1°C.

14. Risk-Averse animals will go here
Risk-Prone animals will go here
1st hour
1st hour
2nd hour
2nd hour
Patch #1
Patch #2

15. Why do animals choose a certain habitat?
Food
Food and the Ideal Free Distribution (Manfred Milinski)

16. Why do animals choose a certain habitat?
Your tax dollars (or mine) at work!
Competitive Unit Model

17. Territories An area actively defended by an animal Why Defend? Anolis
Not Food!
Temperature and Predator Avoidance

18. Territories
Anolis lizard arrive quicker on experimental plots and use the site more.
Lizards LEARN where good habitats are by watching others.
E is experimental where they removed a male from an already occupied territory. C is a control where they tried to mimic what a good habitat might be like (HOWEVER, maybe they don’t know what a good habitat is like). Figure A is amount of time spent on the different sites, while the other graph is how quickly they arrived to experimental/control.

19. Territories - Conditional
Pied Wagtail
Eats insects washing on shore.
Lots of food, allows Satellites (help defend territory….have less knowledge of food pattern)
Byproduct Mutualism in under certain circumstances

20. Territories - Changing
Side-Blotched Lizard
Defend Rocky Territories
Less Rocks, larger territories
More Rocks, smaller territories more competition.
Average 1 female in both 20

21. Territories – Defend for Mating
Some animals might defend territories for mating purpose
Antlered flies – defend territories on rotten logs

24. Migration
When territories or habitats change drastically over time, what do you do?
Migration – Long distance movement and subsequent return from one location to another.

25. How do you know where to go?
Different animals have different abilities to tell where they are:
Piloting – Recognizing landmarks
Compass Orientation – Able to tell specific directions

26. How do you know where to go?
Various Sensory Abilities:
Visual Cues
Stars
Magnetism

29. Migration – Using the Sun
Raised in captivity and then released:
b) first 5 minutes of autumn migration
a) Clock shifted butterflies fly west
c) Natural population fly south
P445. (A) clock shifted birds fly west. B) Laboratory raised butterflies who were raised on a normal light-dark cycle for autumn fly south (C) Butterflies from natural populations fly south. A is the experiment and B is the control that shows you can raise them under artificial conditions that mimic natural sunlight conditions.
Normal condition = fly south in the fall (as winter approaches).
Clock shifted (A)….they think that summer is approaching and they are moving towards a north migration.

31. Migration – Using Earth’s Magnetic Field31

32. Green Sea Turtles 32

33. Green Sea Turtles 33

35. Migration – Using Stars
Emlen funnel (add to words)
Ink on feet mark footprints.
Left (spring), Middle (fall)
Right (when night sky is obscured.

36. Factors Effecting Migration
Some populations migrate, others do not.
Leapfrog effect
A does not leave.
Further north, the further south they travel.
Why?
Might miss food, might not return quick enough for breeding territory.

37. Factors effecting migration
Sometimes migrates
Older, more dominate males migrate less.
Juveniles make the best of what they can, migrate until larger?
Researchers not quite sure.

38. Factors effecting migration
Birds with low fat reserves (A)
Birds with high fat reserves (B)

39. Habitat Selection in Pill Bugs
Types of Movements:
Taxis: Directed movement towards/away from a stimulus
Kinesis: Random movements

40. Choice Chambers

41. Thing to think about?
What do they eat?
What eats them?