1. Population Growth Rate
*YOU WILL BE REQUIRED TO MEMORIZE THESE FORMULAS*

2. Population Growth Rate
This is used to tell an actual rate of growth, not a percentage.
FORMULA: (births-deaths)/time
Ex A rabbit population has 60 births and 12 deaths in 8 months. What is the population growth rate?
(60-12)/8 mo = /8 = rabbits/mo
We can use this to determine how much you expect a population to change and estimate how much it will be at a later point.
Ex. How many rabbits total will be gained in the next year if the growth rate is 6 rabbits/mo?
6*12 = The population will gain a total of 72 rabbits in a year

3. Practice
A deer population has 80 births and 14 deaths in a six month period. Calculate the populate growth rate?
A squirrel population has 47 births and 120 deaths in a three year time period. What is the population growth rate?

4. Percentage Growth Rate
Use this when you need a percent increase or decrease for population growth.
Formula (births-deaths)/initial population size
Ex A population of 300 fish experiences 100 deaths and 200 births in a year. What is the percentage growth rate?
( )/300 = /300 = .33% growth rate

5. Practice
A rat population begins with 375 rats. 1 month later there are 5 new rats and none of the starting rats died. What is the population growth rate percentage?
A population of 789 tulips have a percentage growth rate of if there were 50 births then how many deaths were there?