Name______________Key______________pd____
Population Ecology Problem Set
1. On October 15, 2012, the beginning of the squirrel hunting season for the year, biologist
counted 75 squirrels in a 30-hectare woods. On December 15, 2012, they counted 42 squirrels
in the same woods. What was the density of the squirrel population on
a. October 15?
2.5/hectare
b. December 15?
1.4/hectare
2. A population of 1275 jack-rabbits lives on 450 hectares of western Kansas grassland. Studies
indicate the following rates for this population:
Mortality
2225/year
Natality
3400/year
Emigration
775/year
Immigration
150/year
a. What is the “r” (intrinsic growth rate) for this population?
0.43
b. Assuming the same r, what will be the population size at the end of 4 years?
5331
3. At the end of 2011, a population numbers 100,000. During 2012, there are 1000 births, 800
deaths, 600 immigrants, and 700 emigrants.
a. What is the population size at the end of 2012?
100,100
b. In 2012, what was the
i. Death rate
0.8%
ii. Birth rate
1%
c. Calculate r for this population during 2012.
0.1%
4. Use the graph above to calculate the mean rate of population growth (individuals per day)
between day 3 and day 5. Give your answer to the nearest whole number.
350 individuals/day
5. A colony of paramecium has an intrinsic growth rate “r” of 100 per 1000 in the population per
hour.
a. Starting with 10,000 paramecium, and assuming no environmental resistance, what is
the size of the population at the end of 3 hours?
13310
b. Assume that there is environmental resistance in the form of a 14,000 paramecia
carrying capacity (K) during the 4th hour of growth of the population. Start with the
population size you calculated in “a” above, and find the total number of paramecia at
the end of the 4th hour.
13375