Mitch Lange Jack Connor Kelly Goehring

1. Population Ecology Mitch Lange Jack Connor Kelly Goehring http://www.gdargaud.net/Antarctica/Life/WeddellSeal.jpg

2. What is it exactly? • Studying populations in relation to the environment… • Environmental influences, on population density, distribution, age structure, and population size With more of these guys… http://4.bp.blogspot.com/-fsV4PsAeGIo/TaTBsK4pY9I/AAAAAAAAAjE/hbDsJ0IRVik/s1600/lone%2Bseal2_for%2Bblog-720230.jpg http://2.bp.blogspot.com/-lI0g2NzaOJ8/Tf4udjOH9oI/AAAAAAAAAFo/CTZ0kaz0DAA/s1600/utah-hunting.jpg There will be less of these guys

3. Population Density Population size can be determined in a number of ways: Like number of nests, burrows, tracks, or poop Additions to population occur from : Births Immigration http://4.bp.blogspot.com/_2V1Yi84pHb8/SWwtF8KmDWI/AAAAAAAAAak/xfpC4cpyqTU/s400/il_fullxfull_52550225.jpg http://www.scotlandincolour.com/finch/finches-flying01ll.jpg Population Size

4. Leaving So Soon? • Animals leave because of: Deaths & Emigration: Movement of animals out of a population http://laudyms.files.wordpress.com/2010/03/hawk_eating_prey.jpg http://www.ect.coop/wp-content/uploads/2010/08/Osprey-Leaving-Nest.jpg

5. Dispersion • 3 types: http://bio1903.nicerweb.com/Locked/media/ch53/53_04cRandomDispersion-L.jpg • Clumped: Most common, with individuals in separate patches • Uniform: Evenly spaced, with patterns resulting from interactions • Random: Unpredictable Spacing http://mycozynook.com/36_02aClumpedDispersion-L.jpg http://bio1903.nicerweb.com/Locked/media/ch53/53_04bUniformDispersion-L.jpg

6. Demography • Vital Statistics of populations and their change over time • Particularly looking at birth rate and death rates • Life Table • Age that a person/animal is expected to live to • Cohort= group of individuals of same age. Used to follow the fate from birth to death • Survivorship Curve • Plot to see which data points in a cohort are still alive http://bealbio.wikispaces.com/file/view/survivorship.gif/104532503/survivorship.gif

7. Life History • Some species reproduce in a one shot chance called semelparity • If offspring survival rate is low, this is favored • Others reproduce in the annual cycle called iteroparity • More favorable when there is dependable environment and might be competition for resources • There are many trade-offs between reproduction and survival: • High mortality rates in offspring often exhibit large number of small offspring • High predation rates also factor into large numbers of offspring http://scienceblogs.com/tetrapodzoology/killin_ur_biodiversiteh.jpg

8. Time For Math • Per Capita Rate of Increase is the amount a population goes up over time • Deaths>Births is declining population • Births>Deaths is growing population • Births=Deaths is zero population growth • Intrinsic rate of increase or rmax is when the per capita rate of increase is at its maximum http://2.bp.blogspot.com/_hpxaqo7FS9c/TRKQgN91moI/AAAAAAAAC8E/IYtb9e0-wgE/s1600/maps%2B-%2Bcensus%2B-%2BUS%2Bpopulation%2Bgrowth%2Bsince%2B1790.png

9. Logistic Growth Model • With more population density, each individual has access to fewer resources • The carrying capacity is the max population an environment can support • In this model, the per capita rate of increase declines as carrying capacity is reached • The graph of most real populations is like an S shape • When the population increases to it there is a lag in time where the population can resettle http://www.nabt.org/blog/wp-content/uploads/2009/05/logistic.jpg

10. Things Are Complex • Density Dependency • Death rate rises as population density rises • Also a birth rate falling with rising density • Density Independency • Birth rate or death rate does NOT change with population density

11. Density Dependent • Competition for Resources • More population more competition • Territoriality • Territory space is what the animals compete for i.e: nesting sites • Health • Transmission rate of a disease can wipe out a population • Predation • More food captured means lowered population • Toxic Wastes • Intrinsic Factors • Physiological effects of things like over-reproduction http://www.grguy.net/Q2_30Y3399-Cheetah-marking-300.jpg http://recyclingewaste.files.wordpress.com/2011/09/toxic-waste.jpg

13. Things Are Still Complex • Population Dynamics • Metapopulations • Population Cycles = predictable intervals http://ipmworld.umn.edu/chapters/RadcliffeSlide1.gif

14. Humans

15. People Population Growth • 1962-no longer y^x • Demographic Transition • Developed countries: reproduction rates about = replacement level • Population growth in Developing countries http://www.mongabay.com/images/pop.gif

16. Age Structure • Relative number of individuals at each age

17. Global Carrying Capacity-Humans • Some say a billion, some say a trillion • Ecological Footprint( EF) • Produce all resources, absorb all wastes • Ecological Capacity( EC) • Actual resource base of their country • U.S. EF= 8.4 ha, EC= 6.2 ha • World EF= 1.7 ha http://sunhomedesign.files.wordpress.com/2009/04/cc-graphic1.gif

18. Limiting Factors • Space • Nonrenewable Resources • Renewable Resources • Earth’s Capacity to Absorb Wastes