II. Habitat Selection
1. Dispersal vs choice habitat
2. Important for conservation measures
3. Behavioral Mechanisms:
a. Simple- Random movement response gradient
b. Simple - Chemical cue
i. Volatile odors - plants attract females oviposit
ii. females attract males
c. Simple - Ritual behavior limited
i. mosquito (Anopheles, a malaria vector) India
d. Complex - Hierarchical decision making (Various Scales)
e. Bird Habitat - Hierarchical result stimuli
i. landscape/terrain (navigation capabilities)
ii. nest sites, song, perch feeding, food, drinking site
iii. predator avoidance behavior; foraging behavior
4. Habitat Selection: Two levels
a. Behavior factors dynamic response to environmental variables
b. Evolutionary factors- survival based on habitat selection
5. Evolutionary change Slow compared to habitat change:
a. How much choice genetic-hard wired? vs behavioral?
b. Experiment Chipping Sparrows: (% time spent)
c. Innate preference of sparrows for pine modified early experience
6. Not only visual cues birds etc.
a. Subpopulations of songbirds - prefer certain dialets
7. Other animals select various parameters
a. Open vs brush habitats (desert rodents & deer mouse)
b. Genetic or learned behavior?
8. Evolutionarily- Natural Selection:
a. Directly influencing habitat choice
b. Selects for individuals capacity learn
c. No perfect organism (Usually trade-off qualities)
i. Flexible
ii. Specific
d. Must have suitable genetic variation in populations adjust behaviors
i. Importance of biodiversity on only species but gene pool
ii. Directional selection (teal ducks)
9. Ideal free distribution of habitat selection
a. Predicts trade off between best habitat & overcrowding
b. Equalizes fitness at best and more marginal sites - negative density effects
c. Yellow-legged gulls test in the field of this concept