Question

A population of arctic birds has migrated farther north than previous years. The new location is good for the birds, and the population exhibits exponential growth. As time passes, the population begins to level out and maintain a steady population size. (10 points)

1. Suppose that researchers say ? > 1. What does this mean? (1 point)
2. In the first year, there are 200 births from an original population size of 2000. There are also 100 deaths, 10 emmigrants, and 20 immigrants. What is the value of r? (3 points)
3. Given the r you calculated in part B, estimate the value of ?. (2 points)If you did not successfully find an r in part B, you can use the value 0.123 as your r and still get full credit for part C if you calculate ? correctly.
4. Estimate the population size after 3 years using the initial population size of 2000 and the values calculated above in parts B and C. (2 points).  If you did not successfully find an r in part B, you can use the value 0.123 as your r and still get full credit for part D if you calculate population size correctly.
5. Give an example of a density-independent population size regulator for these birds. (2 points)

Answer 1

At the constant birth rate in Population through time and is never be limited by food or disease is known as Exponential Groth.The formula for Exponential Growth=dNdt=rNdNdt=rN where dNdt is the rate of change in  population size r is the biotic potentialand N is the population size.

if lambda>1 means there is an increase in population.

Value of r can be calculated by the equation

r= Birth-Death/ Actual population

here it is birth=200

death=100

Actual population=2000 so r= 200-100/2000

=.05

ie r is positive and greater than 0 .it means that population is increasing.

Density -independent population size regulator for these birds are weather and cimate,exert their influences on population size regardless of  the population's density.