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Population Dynamics Quiz 4


Bio-geochemical Cycles 
Quiz I

Problem set I

Ecology Test 
Test 1   Test 2
Test 3   Test 4
Test 5   Test 6
Test 7   Test 8
Test 9   M/C 

Energy Calculation 
Quiz 1   Quiz 2

Human Ecology  
Quiz 1   Quiz 2
Quiz 3   

Population Dynamics 
Quiz 1   Quiz 2
Quiz 3   Quiz 4
Quiz 5   Quiz 6

  1. There are 4200 in a column of pondwater measuring 1 cm by 0.25 cm by 2 cm. How many daisies should you find in 200 ml of the pond?

    The volume of column is 1 cm x 0.25 cm x 2 cm = 0.5 cm3. 
    Since 1 cm3 under standard ecological conditions is roughly equal to 1 ml of water, 0.5 cm3 transforms to 0.5 ml. 
    You have 200 ml of water or 400 times the sample volume, therefore you should have 400 times the population or, 400 x 4200 = 1 680 000. 
  2. Red wiggler populations were sampled in quadrats measuring 0.2 m x 0.5 m by 20 cm. From the table of data below, determine how many red wigglers should be found in a sample measuring 10 m by 50 m by 20 cm deep. 
    Quadrat Number Population of Red wigglers
    1 30
    2 64
    3 95
    4 78
    5 98
    6 85

  3. How many red wigglers should there be in a column of soil measuring 0.2 m by 1 m by 2000 cm?
  4. In doing a population study of caribou in a park in Quebec, 200 animals were captured, marked and released. After 2 weeks, 400 animals were captured, 30 of which had the mark from the original two hundred. What is the population of the the caribou? 

    For the sampling question above, many assumptions are made. Some assumptions are technical (i.e., dealing with issues during data collection); some are design-oriented (i.e., things decided before data was acquired); and some of which were theoretical (i.e., decisions about what data is important or what sort of things are ultimately knowable). For the caribou question above, describe 2 specific examples of each class of assumptions and state how each would have an impact on the results.

  5. A population of red-winged blackbirds is growing in an exponential fashion. The average number of offspring per female is 5. Determine the size of the population after 12 generations have elapsed. Assume the parents live forever.
  6. Bacteria can reproduce by binary fission. How many bacteria would be present after 21 generations if the population size was growing in an exponential fashion.
  7. Determine the annual percent growth rate of people in Canada given the following data:
    between 1980 and 1987 the population grew from 24 300 100 to 26 000 200
  8. What is the doubling time for a population of zebra mussels if the average lifespan of a mussel is 9 months and the annual percent growth rate is 2.4 % ?
  9. Determine the annual percent growth rate for a population of sea lions if the herd increased in size from 20 000 in 1989 to 50 000 in 1991.