Fish Ecology
THE UNIVERSITY OF HULL
Department of Biological Sciences Level Five Examination May/June 2011 Fish Ecology Monday 16th May 2011, 9.30 - 11.30 a.m. 2 hours
Answer THREE questions Use diagrams where appropriate Use a separate book for each answer Where shown the % indicates the mark distribution within a question Graph paper provided
Do not open or turn over this exam paper, or start to write anything until told to by the Invigilator. Starting to write before permitted to do so may be seen as an attempt to use Unfair Means.
[58277] Page 1 of 4 [Continued]
Answer THREE questions Use diagrams where appropriate Use a separate book for each answer Where shown the % indicates the mark distribution within a question
Graph paper provided
1.
a)
Discuss the concept of key factor analysis in relation to the generalized life history of fish. (50%) Describe how you would determine total mortality (Z) in exploited fish stocks from catch data. (30%) How is information on mortality used in fisheries management? (20%)
b)
c)
2.
a)
Discuss the adaptive significance of migration in the life history strategies of fish. (50%)
b)
Discuss briefly the relevance of predator prey interactions in structuring aquatic ecosystems. (50%)
3.
a)
Describe the characteristics of fish scales that allow them to be used for age and growth studies. (20%) Briefly describe the principle and method of “back calculating” growth in fish. (30%)
b)
c)
Figure 1 compares the back-calculated growth curve for roach in the River Don (a river in Yorkshire recovering from years of pollution) with the standard growth curve for roach in England and Wales. Explain the differences between the growth curves and what is possibly happening within the roach population of the river. Figure 2 provides the length frequency histogram for the roach population of the river and should be drawn upon to aid your explanation. (50%)
[58277]
Page 2 of 4
[Continued]
Department of Biological Sciences Level Five Examination May/June 2011 Fish Ecology Monday 16th May 2011, 9.30 - 11.30 a.m. 2 hours
Answer THREE questions Use diagrams where appropriate Use a separate book for each answer Where shown the % indicates the mark distribution within a question Graph paper provided
Do not open or turn over this exam paper, or start to write anything until told to by the Invigilator. Starting to write before permitted to do so may be seen as an attempt to use Unfair Means.
[58277] Page 1 of 4 [Continued]
Answer THREE questions Use diagrams where appropriate Use a separate book for each answer Where shown the % indicates the mark distribution within a question
Graph paper provided
1.
a)
Discuss the concept of key factor analysis in relation to the generalized life history of fish. (50%) Describe how you would determine total mortality (Z) in exploited fish stocks from catch data. (30%) How is information on mortality used in fisheries management? (20%)
b)
c)
2.
a)
Discuss the adaptive significance of migration in the life history strategies of fish. (50%)
b)
Discuss briefly the relevance of predator prey interactions in structuring aquatic ecosystems. (50%)
3.
a)
Describe the characteristics of fish scales that allow them to be used for age and growth studies. (20%) Briefly describe the principle and method of “back calculating” growth in fish. (30%)
b)
c)
Figure 1 compares the back-calculated growth curve for roach in the River Don (a river in Yorkshire recovering from years of pollution) with the standard growth curve for roach in England and Wales. Explain the differences between the growth curves and what is possibly happening within the roach population of the river. Figure 2 provides the length frequency histogram for the roach population of the river and should be drawn upon to aid your explanation. (50%)
[58277]
Page 2 of 4
[Continued]