# Chapter 5 - Populations

## 5.1 How Populations Grow

Case Study - Sea Otter Fur Trade

Geographic Range - the area where a poulation lives

Growth rate - how the population size changes

- Positive = increasing
- Negative = decreasing
- Zero = staying the same

Density - number of individuals in an area

Distribution- how they are spaced (clumped, random, uniform)

Age Structure Diagrams - compare population at each age group (rapid, slow, stable)

Data Analysis - population of sea otters in British Columbia (graph analysis)

Population Growth = Birth rate minus Death Rate and Immigration minus emigration

Emigration - movement out of a population | Immigration - movement into the population

Exponential growth

- occurs under ideal condtions
- J-shaped curve
- population increases quickly

Logistic growth

- growth slows or stops
- S-shaped curvie
- population at carrying capacity

## 5.2 Limits to Growth

Density-dependent factors (competition, disease, overcrowding, food availability)

Density-independent factors (random events, natural disasters)

Predator Prey Relationships

- populations fluctuate (go up and down)
- wolf and moose

## 5.3 Human Population Growth

Populations tend to increase (rate of increase changes over time)

Population distribution - where human populations are concentrated (major cities, states)

Demography - study of populations

Demographic transition - dramatic change in population caused by lower birth rates

Age Structure Diagrams - show the size of different age groups

Measuring Population Size

- Mark and Recapture
- Random Sampling

## Classroom Activities and Resources

Limiting Factors and Carrying Capacity (Key, TpT)

Estimating Population Size with Random Sampling (Key, TpT)

Lesson of the Kaibab - graph analysis

Whooping Crane Popoulation - graph and data analysis

Reinforcement: Populations - vocabulary practice