270 likes | 563 Views
St Paul Alaska Reindeer Population. St. Paul Facts. 200 miles from mainland Alaska 44 square miles Good amount of vegetation No Predators for Reindeer No hunting of Reindeer. Book Work. Answers the questions from your book, on pg. 560-561. Question 1, A-F Question 2, A, C, D, H.
E N D
St. Paul Facts • 200 miles from mainland Alaska • 44 square miles • Good amount of vegetation • No Predators for Reindeer • No hunting of Reindeer
Book Work • Answers the questions from your book, on pg. 560-561. • Question 1, A-F • Question 2, A, C, D, H
Problem #1, A (pg. 117 in Notebook) • In 1911 the population was 25 reindeer. What was the size of the population in 1920? What was the difference in the number of reindeer between 1911 and 1920? What was the average annual increase in the reindeer from 1911-1920? Use your graph provided To the nearest 100th
You should of got 1920= about 300 reindeer 1911-1920= increase of 250 Average annual increase was about 28 250 (# of increase) / 9 (years) = average annual increase in reindeer
Problem B • What was the difference in population size between the years 1920 and 1930? What was average annual increase in the number of reindeer in the years between 1920 and 1930?
You should of got 1930= 500 reindeer 1920-1930= increase of 200 Average annual increase was about 20 200 (# of increase) / 10 (years) = average annual increase in reindeer
Problem C • What was the average annual increase in the number of reindeer in the years between 1930 and 1938?
You should of got • In 1938 there were 2000 reindeer. 1930 There were 500 1930-1938 annual increase was 187 1500 (# of increase) / 8 (years) = 187 per year
Problem D • During which of the three time spans did the reindeer population increase the most? 1911-1920 1920-1930 1930-1938
You should of got • The increase was the greatest from 1930-1938
Problem E • What was the greatest number of reindeer found on the island, and what year did it occur?
You should of got • The greatest number was 2000 in 1938.
Problem F In 1950 only 8 reindeer were still alive. What is the average annual decrease in the number of reindeer in the years between 1938 and 1950?
You should of got • 1938-1950=decrease of 1,992 deer 1992 # of difference / 12 years = 166 deer dying per year
Problem #2, A (pg. 118) • St. Paul Island is more than 323 km (200 miles) from the mainland. Could leaving or arriving at the island have played a major role in determining the size of the reindeer population? Explain your answer.
You should have got… • Probably not. St. Paul Island is more than 323 km from the mainland. Reindeer are strong swimmers, but the distance is to great for emigration or immigration to have a major effect.
Problem B • Didn’t have to do
Problem C • St. Paul Island is about 106 km2 (41 square miles). What effect might 2000 reindeer have on the island and its vegetation?
You should have got… • Overgrazing, death of plants, destruction of habitats, accumulation of wastes.
Problem D • Consider all the factors an organism requires to live. What might have happened on the island to cause the change in population size between 1938 and 1950?
You should have got… • Overgrazing resulted in the death of plants and insufficient food. Weakened by a lack of food, the reindeer were prey to disease and the reproductive rate could have declined drastically.
Problem E, F, G • Didn’t have to do…
Problem H • What does this study tell you about unchecked population growth? What difference might hunters or predators have made?
You should have got… • Natural controls take effect and can have drastic results, such as the total population dying out. Predators and hunters might have controlled the population, preventing exponential growth and the destruction of the environment, thus maintaining the carry capacity of the environment.
Critical Thinking(pg. 118-119) Imagine you were the scientists in charge of St. Paul Island and the reindeer. • What would you have done to sustain the population of reindeer?