The following table gives the DDT content (in ppm) of three types of seabird eggs. The eggs were sampled at two different locations along the eastern coast of Canada. The amount of pesticides in bird eggs is a useful indicator of pesticide levels in the environment. Please study the data and answer the following questions:

DDT content in Atlantic seabird eggs

Species Year Fund Bay Atlantic

Leech's Petrel (named near the water surface) (eating small organisms) 1968 no data 1.46

1972 6.81 2.48

1976 1.75 0.75 1980.1984 1.13. 1.05 0.46. 0.40

Atlantic puffin (feeds on small fish)

1968 no data 0.89

1972.1976 2.57. 1.27 0.76. 0.59

1980.1984 1.03. 0.74 0.55. 0.30

Horned Cormorant (feeds on larger fish)

1972 6.51 2.85

1976 1.49 2.18

1980.1984 1.91. 1.07 1.34. 1.88

(a). Describe the general differences in pesticide levels in eggs laid by seabirds nesting near the Bay of Fund and those nesting along the Atlantic coast;

(b). Describes changes in pesticide levels from 1972 to 1984. What caused these changes?

(c). Describe differences in pesticide levels among eggs of different species of seabirds. Give a reason for the difference.