You Are an Aquatic Biologist Studying a Small Lake

Multiple Choice

You are an aquatic biologist studying a small lake. The stream that drains into this lake runs by croplands. You are detecting a pesticide called atrazine in the insects and worms that live in the lake. The predatory birds such as herons and egrets have very high concentrations of atrazine in their blood. The birds prey on the frogs and small fish. What condition best explains the high atrazine level in the birds?

A) Acute effects experienced by the birds
B) Consumption in amounts larger than the lethal dose
C) Chronic residual effects in the birds
D) Biological accumulation and magnification
E) An increase in ecological toxicity