Population Explosion! Just how many redwings are there? It's impossible to be precise, since there is no way someone can check every single place where they might be and count them all. Back in the winter of 1974-1975, scientists estimated that 190 million redwings were wintering in the U.S. Since then, redwings have declined in some areas where wetlands were filled, and increased in other areas where cattails have flourished in ponds. In North and South Dakota, the redwing population has increased about 33% from 1996 through 1999. In any given year, about half of all redwings die. So how can their overall population increase so dramatically? Females usually start breeding their second year, and each female produces about 3-5 eggs, which they raise with the help of their mate. That keeps the males VERY busy, because each male who succeeds in obtaining a territory mates mates with 2-6 females, and sometimes even more! If a nest fails, females will often renest the same season. Overall, one study found that females produce a maximum of 24 surviving babies during their lives, and one male produced 176 fledglings on his territory. That's a lot of new red-winged blackbirds! One thing that has helped them is the increase in cattails that are growing in Dakota wetlands. The cattails are actually not a native variety, and as their population has exploded, the redwings that nest in them have increased to fill the added habitat. As beautiful and exciting as redwings are when they return to their marshes in spring, they cause problems for farmers, especially when their population gets very high. In 2001, the U.S. Department of Agriculture proposed a program to poison 6 million redwings. The U.S. Fish and Wildlife Service refused to grant the proposal, but farmers are having trouble trying to figure out how to deal with the overabundance of red-wings. To learn more, see our Red-wing Poisoning Lesson.
Try This! Journaling and Discussion Questions
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