1. N ATURE U NBOUND L ESSON 3 – P OPULATION C HECKS AND B ALANCES Conservation Mr. Dieckhoff

2. T HE M ISSOURI O TTER Working with the people at your table, answer the following question: What information do you know about Otters? Missouri Department of Conservation Video https://www.youtube.com/watch?v=OzG98Fbx7G4 https://www.youtube.com/watch?v=Qve3jLhMYRI

3. P OPULATIONS Boundaries set by What is the boundary of the Asian Carp? Population Size - Population Density – Dispersion – Clumped Uniform Random

4. M ARK -R ECAPTURE M ETHOD 1. Catching a sample of the population and marking the captured individuals with paint, a leg band, an ear tag, etc.. 2. After marking, release and allowed to mix back into the population 3. After a period of time, a second sample of individuals is collected from the same place Lincoln-Petersen Estimate

5. S AMPLING P OPULATIONS Census – Sample – Quadrats Transects

6. S AMPLING P OPULATION E XAMPLES Black Bears https://www.youtube.com/watch?v=bYoFrPSybiE https://www.youtube.com/watch?v=tJNlstEYHmU Electrofishing https://www.youtube.com/watch?v=unAdz09rjvg Ducks https://www.youtube.com/watch?v=I88MJWpcoH4 Otters https://www.youtube.com/watch?v=_VdQnsG8KFQ

7. P OPULATION S IZE C AN G O U P OR D OWN Increased by – Decreased by – With abundant resources, populations grow quickly Exponential growth – population increases in proportion to its size (J- shaped curve) Per Capita Rate of Growth Compare birth and death rates over time to see if population is increasing or decreasing

8. L IMITING F ACTORS Factors that slow a population’s growth or prevent it from existing in an area Abiotic – Biotic – Density-Independent Factors Limiting factors that affect population regardless of its density Examples – Density-Dependent Factors Limiting factors that affect a population related to its density Examples – https://www.youtube.com/ watch?v=_e1KA8CpPnA https://www.youtube.com/ watch?v=IrTYdG1s1OA

9. T HE H UNTING D EBATE Compensatory Mortality Consider a mallard population in which winter food is a limiting factor. With a large population, there isn’t enough food to go around, and 10,000 ducks die each year of starvation. If hunters kill a percentage of the population, there is more food available to the surviving mallards, and fewer ducks starve. In this example, the number of mallards that die will be the same regardless of whether hunting or starvation is responsible. Thus, if hunters kill 6,000 ducks, 4,000 will die from starvation, and if hunters kill 8,000 ducks, 2,000 will die from starvation. Additive Mortality If hunters kill 5,000 ducks, it would add to the 10,000 that normally die of starvation. Thus, the population would decrease by 15,000 ducks.

10. C ARRYING C APACITY Definition:

11. C ULTURAL C ARRYING C APACITY Number of animals people will tolerate Issues of urban deer: https://www.youtube.com/w atch?v=AbQQ9cItlOo https://www.youtube.com/w atch?v=AbQQ9cItlOo Deer birth rates are high Many does produce twins 10-15% produce triplets Higher in northern Missouri Death rates are falling Fewer predators Hunters take 40-70% of antlered bucks Hunters take 25% of does What has more affect on deer populations? harvesting bucks or does

12. C ONCLUSION 1. Populations – Size, Density, Dispersion 2. Mark-Recapture Method 3. Sampling Populations 4. Population Size Changes 5. Limiting Factors 6. Hunting – Compensatory vs. Additive 7. Carrying Capacity Cultural Carrying Capacity