St Paul AlaskaSt Paul AlaskaReindeer PopulationReindeer Population

St. Paul FactsSt. Paul Facts

200 miles from mainland Alaska200 miles from mainland Alaska 44 square miles44 square miles Good amount of vegetationGood amount of vegetation No Predators for ReindeerNo Predators for Reindeer No hunting of ReindeerNo hunting of Reindeer

Book WorkBook Work

Answers the questions from your book, Answers the questions from your book, on pg. 560-561.on pg. 560-561.

Question 1, A-FQuestion 1, A-F Question 2, A, C, D, HQuestion 2, A, C, D, H

Problem #1, A (pg. 117 in Problem #1, A (pg. 117 in Notebook)Notebook)

1)1) In 1911 the population was 25 reindeer. What In 1911 the population was 25 reindeer. What was the size of the population in 1920? What was the size of the population in 1920? What was the difference in the number of reindeer was the difference in the number of reindeer between 1911 and 1920? What was the between 1911 and 1920? What was the average annual increase in the reindeer from average annual increase in the reindeer from 1911-1920?1911-1920?

Use your graph providedUse your graph provided

To the nearest 100thTo the nearest 100th

You should of gotYou should of got

1920= about 300 reindeer1920= about 300 reindeer

1911-1920= increase of 2501911-1920= increase of 250

Average annual increase was about 28Average annual increase was about 28

250 (# of increase) / 9 (years) = average 250 (# of increase) / 9 (years) = average annual increase in reindeerannual increase in reindeer

Problem BProblem B

What was the difference in population What was the difference in population size between the years 1920 and 1930? size between the years 1920 and 1930? What was average annual increase in the What was average annual increase in the number of reindeer in the years between number of reindeer in the years between 1920 and 1930?1920 and 1930?

You should of gotYou should of got

1930= 500 reindeer1930= 500 reindeer

1920-1930= increase of 2001920-1930= increase of 200

Average annual increase was about 20 Average annual increase was about 20

200 (# of increase) / 10 (years) = average 200 (# of increase) / 10 (years) = average annual increase in reindeerannual increase in reindeer

Problem CProblem C

What was the average annual increase in What was the average annual increase in the number of reindeer in the years the number of reindeer in the years between 1930 and 1938?between 1930 and 1938?

You should of gotYou should of got

In 1938 there were 2000 reindeer.In 1938 there were 2000 reindeer.

1930 There were 5001930 There were 500

1930-1938 annual increase was 1871930-1938 annual increase was 187

1500 (# of increase) / 8 (years) = 187 per 1500 (# of increase) / 8 (years) = 187 per yearyear

Problem DProblem D

During which of the three time spans did During which of the three time spans did the reindeer population increase the the reindeer population increase the most?most?

1911-19201911-1920

1920-19301920-1930

1930-19381930-1938

You should of gotYou should of got

The increase was the greatest from The increase was the greatest from 1930-19381930-1938

Problem EProblem E

What was the greatest number of What was the greatest number of reindeer found on the island, and what reindeer found on the island, and what year did it occur?year did it occur?

You should of gotYou should of got

The greatest number was 2000 in 1938.The greatest number was 2000 in 1938.

Problem FProblem F

In 1950 only 8 reindeer were still alive. In 1950 only 8 reindeer were still alive. What is the average annual decrease in What is the average annual decrease in the number of reindeer in the years the number of reindeer in the years between 1938 and 1950?between 1938 and 1950?

You should of gotYou should of got

1938-1950=decrease of 1,992 deer1938-1950=decrease of 1,992 deer

1992 # of difference / 12 years =1992 # of difference / 12 years =

166 deer dying per year166 deer dying per year

Problem #2, A (pg. 118)Problem #2, A (pg. 118) St. Paul Island is more than 323 km (200 St. Paul Island is more than 323 km (200

miles) from the mainland. Could leaving miles) from the mainland. Could leaving or arriving at the island have played a or arriving at the island have played a major role in determining the size of the major role in determining the size of the reindeer population? Explain your reindeer population? Explain your answer.answer.

You should have got…You should have got…

Probably not. St. Paul Island is more Probably not. St. Paul Island is more than 323 km from the mainland. than 323 km from the mainland. Reindeer are strong swimmers, but the Reindeer are strong swimmers, but the distance is to great for emigration or distance is to great for emigration or immigration to have a major effect.immigration to have a major effect.

Problem BProblem B

Didn’t have to doDidn’t have to do

Problem CProblem C

St. Paul Island is about 106 km2 (41 St. Paul Island is about 106 km2 (41 square miles). What effect might 2000 square miles). What effect might 2000 reindeer have on the island and its reindeer have on the island and its vegetation?vegetation?

You should have got…You should have got…

Overgrazing, death of plants, destruction Overgrazing, death of plants, destruction of habitats, accumulation of wastes.of habitats, accumulation of wastes.

Problem DProblem D

Consider all the factors an organism Consider all the factors an organism requires to live. What might have requires to live. What might have happened on the island to cause the happened on the island to cause the change in population size between 1938 change in population size between 1938 and 1950?and 1950?

You should have got…You should have got…

Overgrazing resulted in the death of Overgrazing resulted in the death of plants and insufficient food. Weakened plants and insufficient food. Weakened by a lack of food, the reindeer were prey by a lack of food, the reindeer were prey to disease and the reproductive rate to disease and the reproductive rate could have declined drastically.could have declined drastically.

Problem E, F, GProblem E, F, G

Didn’t have to do…Didn’t have to do…

Problem HProblem H

What does this study tell you about What does this study tell you about unchecked population growth? What unchecked population growth? What difference might hunters or predators difference might hunters or predators have made? have made?

You should have got…You should have got…

Natural controls take effect and can have Natural controls take effect and can have drastic results, such as the total drastic results, such as the total population dying out. Predators and population dying out. Predators and hunters might have controlled the hunters might have controlled the population, preventing exponential population, preventing exponential growth and the destruction of the growth and the destruction of the environment, thus maintaining the carry environment, thus maintaining the carry capacity of the environment.capacity of the environment.

Critical ThinkingCritical Thinking(pg. 118-119)(pg. 118-119)

Imagine you were the scientists in charge Imagine you were the scientists in charge of St. Paul Island and the reindeer.of St. Paul Island and the reindeer.

1.1. What would you have done to sustain What would you have done to sustain the population of reindeer?the population of reindeer?