- Several small bird populations are in decline with a study citing a net loss of almost three billion birds since 1970.
- Several factors have caused the mass loss including urbanization, habitat loss, and climate change.
- Measures can be taken to help prevent the loss of existing populations such as lessening or even eliminating the use of pesticides and planting a garden with native species.
Since 1970, researchers and scientists have been collecting data on 529 bird species and have noticed a trend: certain populations have been in decline over the course of the last 48 years. In fact, NPR reports that around three billion birds have disappeared across a dozen species during this time.
In a study published in Science, researchers write that the population losses span several "North American avifauna" including birds that were once quite prevalent such as warblers and sparrows. Inversely, there are bird populations that are on the rise—mainly, birds of prey like the bald eagle and some waterfowl, including ducks and geese.
Ken Rosenberg, an applied conservation scientist with Cornell University's Lab of Ornithology, tells NPR that duck and geese populations are at the highest they've ever been thanks to hunters who "have raised their voices" in order to assure that they have a large pool of birds to hunt.
According to the study, population decline is not only happening to rare species. It's also affecting "many widespread and common species that may be disproportionately influential components of food webs and ecosystem function," meaning that there's a chance that increasing numbers of dying birds could prove disastrous for unrelated species and environments.
Researchers gathered data from "long-running surveys done with the help of volunteer bird spotters" and utilized 143 weather radars to obtain data across the span of 10 years about migration patterns. The results are dismal, showing that a staggering 90 percent of the lost populations come from 12 types of birds: American sparrows, wood warblers, blackbirds, and finches.
Elise Zipkin, assistant professor and head of the Zipkin Quantitative Ecology Lab at Michigan State University, told Popular Mechanics that the emphasis the study places on the effects of biomass loss is an important note to touch upon."It's not extinction but losing these individuals can have a huge [negative] impact on ecosystems," she says.
Zipkin also notes the importance of conservation and preservation efforts before populations begin rapidly declining."Just because a species hasn't gone extinct or isn't even necessarily close to extinction, it might still be in trouble," Zipkin told NPR.
The study cites an "urgent need to address the ongoing threats [against bird populations] to avert continued biodiversity loss and potential collapse of the continental avifauna."
If you want to get involved in preservation efforts, there are a few things you can try. Zipkin suggests planting a garden with native species. The National Wildlife Federation created a lookup tool where all it takes is a zip code to see what's native to your area.
"If you have land, consider letting it go natural. Use less chemicals in your lawn, vote for people who take conservation efforts seriously," Zipkin says.
