Bee-killing pesticide linked to bird declines

A pesticide that has been blamed for killing large bee colonies has now been linked to bird population declines, according to a study.

The study, published Wednesday in Nature, linked imidacloprid to declines in the population growth rate of 14 bird species after it was introduced in the Netherlands in the 1990s, the Los Angeles Times reported.


Imidacloprid belongs to the neonicotinoid family, a pesticide that has been blamed for massive deaths of domesticated honeybees, which are important for pollinating food crops. The study focused on high amounts of imidacloprid on water surfaces.

Ruud Foppen, a co-author of the research, cautioned that researchers found a “very convincing” correlation, but not a causation.

Researchers did not rule out the possibility that ingesting the pesticide killed birds. Instead, they believe that a reduction in the volume of available insects during mating season made it harder to reproduce, the Times said.

The highest concentrations of neonicotinoids correlated with a 3.5 percent drop in the number of birds of those species, the study found. Researchers corrected for land use changes in their calculations.