Pollinators — animals that move pollen from one plant to another while feeding — enable the production of fruits and seeds through plant fertilization. This not only provides food sources crucial to native wildlife, nearly one third of the food we eat requires pollination. Most pollinators are flying insects such as bees, wasps and butterflies as well as flies and beetles, and like other wildlife, are greatly impacted by habitat loss, growing populations of invasive non-native species, a changing climate and other threats such as disease.
One threat looms largest of all: chemical exposure. The class of insecticides known as neonicotinoids pose a pervasive threat across a variety of environments — from agricultural fields, to home gardens and our waterways. Based on accumulating scientific evidence, New Jersey Audubon is calling for increased scrutiny and a more limited use of these products to avoid further impacts to already imperiled pollinator populations.
New Jersey beekeepers report nearly half their honeybees die off each year, significantly higher than the national average. Our wild native bees also provide pollination services to New Jersey crops; they forage in colder and wetter conditions than honeybees and significantly supplement crop production. In 2017, the Rusty Patched Bumblebee was listed as an endangered species, marking the first time a bumblebee has reached endangered status in the U.S. This species, known as an excellent pollinator of cranberries and other crops, was once commonly distributed across the East (including New Jersey) and Midwest but disappeared from 87 percent of its range.
Although many causes contributed to this disappearance, the U.S. Fish and Wildlife Service cited neonicotinoids as a significant factor. Pollinators encounter these broad-spectrum systemic insecticides when feeding because they are readily absorbed by plants either by the roots or leaves and then transported throughout plant tissues, nectar and pollen.
Death by a thousand cuts
While certain levels of the chemicals can cause outright mortality, research shows that neonicotinoids also impact bee behavior by impairing foraging, navigation and motor function, leading to disoriented and inefficient worker bees that struggle or fail to carry out basic survival tasks. Studies also show that neonicotinoids weaken bee immune systems and thus jeopardize colony survival, as well as reduce reproductive success. Combined with other stressors encountered by pollinators, including other chemicals such as fungicides, exposure to these chemicals can culminate in death — of entire colonies — by a thousand cuts.
Many studies focus on bees, but impacts to other pollinator species are also documented, such as reduced survival of butterfly and moth larva following neonicotinoid soil injections. The chemical properties of neonicotinoids allow for easy transport through our soils and to our waters and cause declines of aquatic and other invertebrates, such as mayflies, that are critical to supporting aquatic and terrestrial food webs. This reduction in prey availability has in turn reduced bird populations in areas with elevated surface water concentrations of neonicotinoids. The evidence indicating impacts to a variety of species from neonicotinoid use is not lacking. But a plan to more closely monitor and limit their use is.
While a Federal Pollinator Task Force was created in 2014, this has yet to translate to any concrete regulation by the Environmental Protection Agency and recent decisions rolled back existing regulations. For example, the Trump administration reversed a ban on neonicotinoid use on National Wildlife Refuge properties in August 2018. It is more crucial than ever to pursue greater pollinator awareness and protections at the state level.
New Jersey Audubon has partnered with several legislators on this front and recently-enacted legislation will help bring a greater awareness of the plight of pollinators and some improved procedures.
Additional effort is needed to stave off even more drastic pollinator declines and now is the time for an increased focus and action on neonicotinoids specifically, which are available for use without limitation by the agricultural sector and the public. Thoughtful changes to reduce these chemicals in our environment — such as a ban on outdoor use — help to protect not only pollinators, but entire food chains.