1. POPULATIONS

2. What is population?
A population is a group of individuals of the same species living in the same area.

3. Population Characteristics
There are three main characteristics of a population.

4. 1. Geographic Distribution
is where the organisms
can be
found
on earth.

5. 2. Density
The density of the population is the number of organisms living in a certain amount of space.

6. Population Density Listed by State01
 New Jersey
1,205 inhabitants per square mile 02
 Rhode Island
1,016 inhabitants per square mile (392 /km2) 26
 Texas
98.07 inhabitants per square mile (37.87 /km2) 50
 Alaska
1.264 inhabitants per square mile (0.488 /km2)

7. World Population Density

8. 3. Growth Rate
Growth rate is affected by the number of births, number of deaths, and individuals leaving/coming to the area.

10. LIMITING FACTORS
Competition, predation, parasitism, disease, drought, climate extremes, and natural disasters can all cause changes in a population.
A cow noses around for a piece of green grass at the bottom of a dry stock tank at a ranch near Manor. Many ranchers have been forced to sell off their herds as record drought conditions have persisted across Central Texas. 7/27/2011

11. CARRYING CAPACITY
Carrying Capacity is the number of organisms that an ecosystem can support.
This balance allows the ecosystem to remain healthy.

12. What is happening to the population of deer?

13. The population of deer passes its carrying capacity.

14. Then the population of deer decreases until it finally levels out.

15. What was happening to the deer?

16. Predator- Prey Relationships
Organism being hunted
PREDATOR
Organism hunting

17. Why do you think these organisms show a predator/prey relationship?

18. As the population of wolves increases, the number of moose decreases….

19. When the number of wolves decreases, the number of moose increases.

20. DENSITY DEPENDENT FACTORS
Limiting factor that depends on the populations size. Examples- disease, competition, predation, and parasitism
22 March 2012
UN warns that foot-and-mouth disease outbreak in Egypt threatens entire region

21. DENSITY INDEPENDENT FACTORS
Limiting factor that DOES NOT depend on the populations size. Examples- natural disasters, seasonal cycles, or human activities

23. Density Dependent (DD) or Independent (DI)?
1. A severe flood wipes out the cattle population near the Mississippi River.
2. Due to severe overcrowding in an Asian village, many children do not survive to reach adulthood.
3. The eruption of Mt. St. Helens destroys most of the wildlife in the immediate vicinity of the volcano.
4. Travelers who venture into a crowded African village become infected with a disease caused by parasites.
5. Due to stress, large numbers of female mice miscarry their young and fail to reproduce.

24. Density Dependent (DD) or Independent (DI)?
1. A severe flood wipes out the cattle population near the Mississippi River. DI
2. Due to severe overcrowding in an Asian village, many children do not survive to reach adulthood.
3. The eruption of Mt. St. Helens destroys most of the wildlife in the immediate vicinity of the volcano.
4. Travelers who venture into a crowded African village become infected with a disease caused by parasites.
5. Due to stress, large numbers of female mice miscarry their young and fail to reproduce.

25. Density Dependent (DD) or Independent (DI)?
1. A severe flood wipes out the cattle population near the Mississippi River. DI
2. Due to severe overcrowding in an Asian village, many children do not survive to reach adulthood. DD
3. The eruption of Mt. St. Helens destroys most of the wildlife in the immediate vicinity of the volcano.
4. Travelers who venture into a crowded African village become infected with a disease caused by parasites.
5. Due to stress, large numbers of female mice miscarry their young and fail to reproduce.

26. Density Dependent (DD) or Independent (DI)?
1. A severe flood wipes out the cattle population near the Mississippi River. DI
2. Due to severe overcrowding in an Asian village, many children do not survive to reach adulthood. DD
3. The eruption of Mt. St. Helens destroys most of the wildlife in the immediate vicinity of the volcano.
4. Travelers who venture into a crowded African village become infected with a disease caused by parasites.
5. Due to stress, large numbers of female mice miscarry their young and fail to reproduce.

27. Density Dependent (DD) or Independent (DI)?
1. A severe flood wipes out the cattle population near the Mississippi River. DI
2. Due to severe overcrowding in an Asian village, many children do not survive to reach adulthood. DD
3. The eruption of Mt. St. Helens destroys most of the wildlife in the immediate vicinity of the volcano.
4. Travelers who venture into a crowded African village become infected with a disease caused by parasites.
5. Due to stress, large numbers of female mice miscarry their young and fail to reproduce.

28. Density Dependent (DD) or Independent (DI)?
1. A severe flood wipes out the cattle population near the Mississippi River. DI
2. Due to severe overcrowding in an Asian village, many children do not survive to reach adulthood. DD
3. The eruption of Mt. St. Helens destroys most of the wildlife in the immediate vicinity of the volcano.
4. Travelers who venture into a crowded African village become infected with a disease caused by parasites.
5. Due to stress, large numbers of female mice miscarry their young and fail to reproduce.

29. Now you are going to make a graph of the carrying capacity of the Kaibab deer……..

30. Background Before 1905, the deer on the Kaibab Plateau were estimated to number about The average carrying capacity of the range was then estimated to be about 30,000 deer. On November 28th, 1906, President Theodore Roosevelt created the Grand Canyon National Game Preserve to protect the "finest deer herd in America.“ Unfortunately, by this time the Kaibab forest area had already been overgrazed by sheep, cattle, and horses. Most of the tall grasses had been eliminated. The first step to protect the deer was to ban all hunting. In addition, in 1907, The Forest Service tried to exterminate the predators of the deer. Between 1907 and 1939, 816 mountain lions, 20 wolves, 7388 coyotes and more than 500 bobcats were killed. Signs that the deer population was out of control began to appear as early as the range was beginning to deteriorate rapidly. The Forest Service reduced the number of livestock grazing permits. By 1923, the deer were reported to be on the verge of starvation and the range conditions were described as "deplorable.“ The Kaibab Deer Investigating Committee recommended that all livestock not owned by local residents be removed immediately from the range and that the number of deer be cut in half as quickly as possible. Hunting was reopened, and during the fall of 1924, 675 deer were killed by hunters. However, these deer represented only one-tenth the number of deer that had been born that spring. Over the next two winters, it is estimated that 60,000 deer starved to death. Today, the Arizona Game Commission carefully manages the Kaibab area with regulations geared to specific local needs. Hunting permits are issued to keep the deer in balance with their range. Predators are protected to help keep herds in balance with food supplies. Tragic winter losses can be checked by keeping the number of deer near the carrying capacity of the range.