Letter to the Editor

Talk about it

Saving Peregrine falcons: Northern Minnesota’s conservation success story

One of the fastest animals in the world, flying up to 200 miles per hour and killing prey by dive-bombing small birds in the open air, the peregrine falcon has had a rich history along the shores of Northern Minnesota.

Between the years of 1946-1962, DDT poisoning resulted in the severe decline of peregrine populations across the United States. Animals low on the food chain come in contact with the chemical, which is stored in their fat. When predators, like peregrine falcons, consume many of these animals, the amount of toxin they ingest is amplified. These high concentrations alter the peregrine’s calcium metabolism, resulting in thin eggshells. Peregrine eggs can normally

support a weight of around 70 pounds, but the eggs the affected peregrines were producing only supported about two pounds, meaning mother peregrines would easily crush their eggs in the nest. Fortunately, peregrine falcons have now recovered, after their population was reduced to only 19 pairs in the United States.

Peregrine populations this year have seen a big boost, with such a warm winter skewing biological triggers. Due to the efforts of the state parks and volunteers, peregrine populations in Minnesota have surpassed pre-DDT levels. Despite these improvements, we can’t forget how little we know about how pesticides can affect ecosystems.

Although DDT is now banned, other potentially harmful pesticides are still in use. Extensive preserves of state land along the North Shore have helped keep peregrine habitat safe, allowing even fragile populations to thrive. As the Audubon Society points out, overall bird populations have declined more than 50 percent since 1967.

It is the continued protection of habitat and careful use of pesticides that will prevent the loss of noble birds like the peregrine falcon in the

future.

Tags: two harbors