A new study published in Nature concluded that the presence of high levels of the common neonicotinoid pesticides was directly correlated with population declines in 14 bird species. In recent years, the chemicals have been identified as a cause of major die-offs in domestic honeybees, and are likely a factor in large declines in wild bees and butterflies.
Although the study was done in The Netherlands, researchers and biologists stress that there is no reason to believe that things are any different here in the United States.
Neonicotinoids are insecticides, that since 1990, have been widely used in agriculture and gardening.
Penny Miller is a Volunteer Wildlife Rehabilitator at Wild Bird Rescue in Wichita Falls. She says that the insecticides can affect the species of birds in two different ways.
"Primarily it's a concern of killing of the insects for insect eating birds," Miller says, "but there has been a recent study that showed because the insecticide is put on the seeds themselves. The birds that do ingest the seeds, it can poison them."
The seeds that are most often coated with the chemicals, according to Miller, are corn and canola. Researches recently found that because of these pesticides, between 2003 and 2009, bird populations shrank at an annual average rate of 3.5%.
"The chemicals do remain in the environment for several years after they're sprayed," Miller added, "so a build up can be problematic the fact that the insects are covered in them and ingest them. The birds eat them, and the poison, it affects them."
It would be difficult to duplicate the study here in the U.S., as there are no data sets of neonicotinoid levels across North America. However, the Environmental Protection Agency plans to complete a review of these pesticides by the year 2020.