Bird loss

Wed. Oct. 2, 2019

Click below to listen to my 2 min. Garden Bite radio show: Bird loss

I was astonished when I heard a report that North America has lots nearly 3 billion birds since 1970. Smithsonian Magazine reports that a study in Science Journal says in less than half a century, the avian population of the continent has declined by some 29 percent, or more than one in four birds.

Baltimore Oriole

For the first time, researchers found that threatened species aren’t the only birds suffering population loss. In fact, common birds—including sparrows and blackbirds—are taking the biggest hit. You might wonder, how they count birds.

grassland sparrow by Cornell Lab

The new study used nearly 50 years of monitoring data collected largely by bird watchers and citizen scientists. These efforts include the North American Breeding Bird Survey coordinated by the United States Geological Survey and the Canadian Wildlife Service, Audubon’s Christmas Bird Count, and the International Shorebird Survey. The team then cross-referenced bird count data with radar data from 143 weather satellites that have been used to track migrating birds at night for the last decade.

More than 90 percent of the total loss can be attributed to just 12 bird families, including sparrows, warblers, blackbirds, larks and finches. Some of these widespread birds are so-called “habitat generalists,” or birds that can thrive just about anywhere. The large-scale loss of these hardy birds reveals the extent to which avian animals across the world are struggling to survive.


There are lots of kinds of warblers, each so pretty!

Chestnut sided warbler by AllAboutBirds – the Cornell Lab of Ornithology

Not all birds are in decline, wetland birds and waterfowl, a subset of wetland birds are thriving, up an astounding 56 percent from 1970s numbers.

Common Gallinule and American Coot, Audubon Great Lakes Priority Marsh Bird Species. Photo: Photo: Scott Kinsey/Great Backyard Bird Count

Some resources:

Audobon Great Lakes – Wetland restoration

Audobon Minnesota – Marshland survey