A Wisconsin common loon demographic model was developed to evaluate population performance within a 5000 km2 risk-assessment region of northern Wisconsin
The 5stage deterministic projection matrix model predicts an annual growth rate of 0.9988 by using adult survival, fertility, and juvenile recruitment rates measured in the risk-assessment region during 2002–2004.
Controlled dosing studies with loons (chick survival and hatching rates), combined with exposure assessment of the Wisconsin loon population, indicate that 10% of northern Wisconsin loon chicks have exposure levels associated with toxicity in the laboratory and 10% of adult female loons have exposure levels associated with a 30% reduction in egg hatching rate