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Deer and Wolf Study In 1983 the deer population of an island forest reserve about 200 square kilometres in size was about 2000 animals. Although the island had excellent vegetation for feeding, food supply obviously was limited. The forest management personnel feared that overgrazing might lead to mass starvation. Since the area was too remote for hunters, the wildlife service decided to bring in natural predators to control the deer population. It was hoped that, eventually, natural predation would eliminate the weakest deer, thereby, preventing the herd from becoming too large, while at the same time, increasing the quality of the herd. In 1984, 10 wolves were flown into the island. The results of the natural predator program are presented below:

Year

Wolf Population

Deer Population

Deer Offspring

1984 1985

10 12

2000 2300

800 920

Deer Killed due to Predation 400 480

Deer Population Killed due Change to Starvation 100 300 240 200

1986 1987 1988 1989 1990 1991 1992 1993

16 22 28 24 21 18 19 19

2500 2360 2244 2118 2066 2014 2060 2080

1000 944 996 836 788 766 780 790

640 880 1120 960 840 720 760 760

500 180 26 2 0 0 0 0

-140 -116 -150 -126 -52 46 20 30

Questions: 1. Would it be better for the ecosystem if more wolves had been introduced in 1984? Explain why. if they were more wolves in 1984 there would also be less dears so on 1985 there would be more wolves and less dear and it would decrease a lot more and it would be worse because about the same amount of deers were lost as were made so its a circle and if they added more wolves it would mess it up. 2. Explain why the wolf population declined after 1989 the wolves population started to decrease because the older wolves started to die from natural causes and sometimes wolves kill each other to gain dominance. 3. In which year was deer starvation the greatest? From the data and your knowledge of ecology, explain why so many deer died in 1986 the most deers died from starvation i think this because they was the most deers so they were eating the most food and some deers could not get any food and died 4. Explain what might have happened if human hunters had been allowed to kill half of the wolf population in 1987 for bounty. (hint think of what would happen to the deer and the rest of the ecosystem) then around half of the deers that got killed that year would have survived and that is over 400 deersand that is a lot so that means a lot more deers would have died from starvation 5. You will notice that there is a time lag between the population changes of wolves and deer on your graph. This is what usually happens between predator and prey populations. a. Label it on your graph. ? b. Explain why there is a time delay?

6. How does the size of the deer population influence the number of wolves on the island? If there are more deers the wolves would have more food to make babies and feed them. 7. If no human hunting is allowed, what natural mechanisms will control the wolf population? really the only other thing that can control the number of wolves is the number of deer because they need to eat the deer and also other wolves...