Assignment -
Create an Excel file, the name of the file should be contain your last name, e.g., "Smith2.xls" or "Smith2.xlsx". The two first problems are worth 20 points. The third problem is for extra credit and is worth 8 points. Due Date: May 9, 11:59pm. There is an early submission bonus of 1 point/day and a deduction of 1 point/day for late submission. You have an unlimited number of attempts to submit; only the highest grade counts.
1. Population projection table
Here is a partial life/fecundity table for a cohort of zebra mussels, which is a notorious invasive aquatic species.
|
Age (x)
|
nx
|
bx
|
|
0
|
500
|
0
|
|
1
|
50
|
8
|
|
2
|
25
|
12
|
|
3
|
0
|
0
|
Imagine that 200 individuals of 2 year-old zebra mussels (Age 2) were introduced to a lake. Your task is to use the survivorship and fecundity data from the table above to predict how the mussel population in the lake will grow for the next 15 years.
In your Excel file create a worksheet "Mussels" and construct a population projection table (follow Table 9.6 in Smith & Smith as an example) for a 15-year period. Calculate population size N(t) and finite multiplication rate (or finite rate of increase) λ for each year. Show all necessary intermediate steps and values (see Table 9.5 in Smith & Smith). Round λ values to second decimal place. When does this population achieve a stable age distribution?
Construct a plot showing how population size (Nt) changes over 8 years.
2. Exponential population growth
Whooping Crane is an endangered bird, only one of two cranes species native to North America and the tallest bird on the continent. The species almost disappeared by 1941, but conservation efforts rescued it from extinction. A survey of Whooping Cranes conducted in January 2016 in a wildlife refuge in Texas showed that there were 280 birds in the population. 70 of these birds were captured, banded, and released. The next survey conducted in January 2017 found 300 cranes, while 20 rings from dead birds have been returned during this period. Estimate λ and r and project population size by January 2021 assuming constant birth and death rates and no resource limitation (exponential growth). What is per capita birth rate in this population? Show calculations in a worksheet called "Cranes".
Extra credit: Half of the Whopping Cranes in Texas are infected by parasitic coccidia (protists) that cause an inflammatory disease coccidiosis. The death rate of infected cranes is twice as high as that of healthy birds.
What the population size of cranes in Texas would be by January 2021 if there was no coccidiosis starting from 2015? Show calculations in the same worksheet "Cranes".
Attachment:- Assignment Files.rar