ST. PAUL — North America has lost more than a quarter of its bird population, or nearly three billion birds, over the past half-century.

Carrol Henderson has seen this decline among some of Minnesota’s bird populations. He is the recently retired director of the Nongame Wildlife Program at the Minnesota Department of Natural Resources.

Henderson said the western meadowlark, which is down nearly 8%, and the grasshopper sparrow, down more than 7%, have seen the steepest declines.

“These are all types of species which have been largely reduced to very small numbers on prairie regions where they were once extremely common,” Henderson said.

Henderson also notes what other experts have noted in recent years: a gradual decline in the state’s pheasant population.

The most recent data tracking Minnesota’s bird population is from the Breeding Bird Survey. The USGS Patuxent Wildlife Research Center, the Canadian Wildlife Service, and the National Wildlife Research Center jointly coordinate that survey.

Other takeaways from Minnesota’s numbers: Of the 210 MN species analyzed in the survey, 58% show negative population trends; 14% appear stable; and 27% appear to be increasing. Species on the increase include the bald eagle, wild turkey and Canada goose.

What’s causing the changes?

The factors leading the species decline in Minnesota mirror what’s happening at the national level.

Henderson cites changes to the region’s landscape such as agriculture production.

“When you talk about an increase in productivity for crop production, then you have a comparable dramatic decrease in bird life, as well as insect life,” Henderson said.

Recent data from the U.S. Department of Agriculture show the average Minnesota farm gaining in size. Henderson said that, along with urbanization, can have a major effect. Grasslands are one of Minnesota’s most imperiled habitats, he said, and when insects that occupy these areas are wiped out, the birds that rely on them start to go away, too.

Precision farming to the rescue

In recent years, Minnesota farmers have been more mindful about implementing conservation practices.

When it comes to helping natural habitats, precision farming is considered one way the agriculture industry is trying to scale back damaging landscape changes.

David Mulla, head of the Precision Agriculture Center at the University of Minnesota, said this type of farming uses technology, such as GPS and drones, to ensure that land doesn’t go to waste.

“It could involve retiring land from production if the land is marginal. These could be near sensitive areas that are used by birds and other animals,” Mulla said.

Precision farming also aims for more accuracy in spreading around fertilizer and pesticides that could be harmful to animals.

Such efforts give bird lovers like Carrol Henderson hope that species they don’t see much of any more will once again flourish in Minnesota.