October 17, 2019

Birds Are Disappearing

2 minutes

A new analysis, published in the journal Science, reports that the number of birds in the United States and Canada has fallen by 29% since 1970. There are 2.9 billion fewer birds in the two countries now than there were 50 years ago.

The analysis is the most comprehensive attempt to date to look at the

status of avian populations. The results

were a shock to researchers and conservation organizations.

It is well-known that some bird species have become vulnerable to

extinction, but the new study, which surveyed more than 500 species, uncovered

steep losses even among such traditionally abundant birds as robins and

sparrows.

There appear to be multiple causes for the steep declines. The largest ones are likely habitat loss and

the wider use of pesticides. Rachel

Carson’s 1962 book Silent Spring warned of the dangers of pesticides and

took its title from a world that has lost its birds.

The survey includes 76% of all bird species in the US and Canada, but actually represents almost the entire population of birds. Grassland species have suffered the biggest declines by far, as a result of modern agriculture and development. Pesticides, such as neonicotinoids, make it harder for birds to put on weight needed for migration, delaying their travel.

There are a few bright spots: bald eagles are thriving, and falcon and waterfowl populations are on the upswing. These are species that have been the subject of conservation measures in recent decades.

Stopping the bird decline will require a great deal of effort to

defend habitats, restrict chemicals, and redesign buildings. Without that effort, birds will continue to

disappear.

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Birds Are Vanishing From North America

Photo, posted April 1, 2012, courtesy of Barry Skeates via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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