Bee deaths linked to blend of chemicals

ALBANY, N.Y. _ Combinations of chemicals commonly used to protect fruit orchards across the state can poison honeybees and could be helping fuel a mysterious, ongoing bee die-off, according to research from Cornell University.

Findings about how chemicals used to combat insect pests and fungus can create a powerful combination fatal to bees could be another major clue into a global malady called colony collapse disorder, which has killed millions of bees around the world over the last decade.

"This is probably the most major finding on this in the last three years," said Scott McArt, an entomology scientist at Cornell whose research is part of a report issued recently by the state Department of Agriculture and Markets.

The report examines what the state can do to protect beleaguered bees, butterflies and other pollinating insects that are critical for apples, grapes, and other flowering crops, which bring hundreds of millions of dollars annually to New York's economy. All such crops rely on insect pollination, normally provided by commercial beekeepers who bring in their hives.

New York's bees have been dying at an alarming rate. Losses to commercial beekeepers, who have about 80,000 bee colonies, have run between 44 percent and 54 percent annually during the past three years, according to the state report. Continued annual losses greater than 18 percent are considered economically unsustainable.

Colony collapse disorder occurs due to the sudden disappearance of a colony's worker bee population. Without worker bees, the queen bee and young brood eventually starve.

"Pollinators provide significant contributions to our agricultural industry and our food supply," according to a statement by agriculture Commissioner Richard Ball. "By researching threats and providing new opportunities to monitor for disease, we can better safeguard their health."

McArt's research raises new concerns about a controversial class of long-lasting pesticides called neonicotinoids, which were banned for outdoor use in the European Union in April after being restricted since 2013 due to preliminary links to bee deaths. Some research has suggested that the chemical can disrupt the bees' navigation systems or memory, making them unable to locate their hives.

Neonicotinoids are also found in insecticides sold for home use on plants and lawns and in treated plants available from some nurseries.

In 2018, Maryland became the first state to ban neonicotinoids _ called neonics for short _for home and garden use. In Canada, provincial officials in Ontario are phasing in rules to require corn and soy farmers to prove they need the chemical.

Major retailers like Home Depot and Lowe's have decided to either stop selling neonics-treated plants or require explicit labels so consumers who choose to do so can avoid buying those plants.

The chemical industry maintains that neonics, which have been in widespread agricultural use in the U.S. since the late 1990s, are safe. Unlike earlier insecticides, which break down rapidly and lose effectiveness, neonics are long-lasting and persist in the environment.

Since neonics are the world's most commonly used pesticide, "this is a most controversial topic," said McArt. "Neonicotinoids do contribute to the pesticide risk to bees here in New York."

His research found dangerous interactions between a neonicotinoid called thiamethoxam - which is used in the state's thriving vineyard industry and elsewhere _ and a fungicide called myclobutanil _ which is also used to protect grapes, as well as apples, another major New York crop, and other fruits and berries.

The synergy between insecticides and fungicides can create a much more powerful toxic effect than either chemical has alone to "greatly increase bee mortality," according to the state report citing Cornell's research. In one instance, the toxic effect was increased by 1,000 percent.

Thiamethoxam is one of three major types of neonicotinoids sold globally, along with clothianidin and imidacloprid. McArt said Cornell will be creating a cost-benefit analysis on the potential insecticide and fungicide combinations to screen for the most dangerous combinations.

Kathryn J. Boor, dean of Cornell's College of Agriculture and Life Sciences, called the work "cutting-edge science."

She added, "Pollinator health is inextricably tied to New York's agricultural health. Protecting the diverse pollinator populations is crucial to safeguarding our food supply and our farmers who rely on their services."

A spokesman for the New York Grape and Wine Foundation, which touts the industry as a $4.8 billion economic engine to the state, referred a reporter's questions back to McArt.

Altamont beekeeper Stephen Wilson, who served on a 2016 state task force that studied the issue, said the scientific findings from Cornell underscore the serious threat faced by bees and other pollinators.

The task force's initial report drew some criticism from Wilson and other opponents who felt it soft-pedaled the issue of pesticide risk. The report blamed bee deaths on factors beyond insecticides, such as poor nutrition, loss of foraging habitat, parasites, pathogens, lack of genetic diversity and poor land management practices.

Wilson renewed his call for the state to require the registration of bee hives, as a way to better study potential problems facing beekeepers. Wilson spent 15 years on the state Apiary Industry Advisory Council, which consults with state officials on bee issues. Bill Cooke, government affairs director of Citizens Campaign for the Environment, said the report supports his call for a moratorium on neonicotinoid use in the state. "This combination effect with fungicides is clearly off the charts," said Cooke.

"This science supports the elimination or further restriction of their use, while we continue to gather more science on the issue," Cooke added.

The state plans to have Cornell conduct a feasibility study on potential "further regulation" of thiamethoxam and cyfluthrin, another commonly used insecticide that is not related to neonicotinoids. State regulations on thiamethoxam have been in place since 2002, while the regulations for cyfluthrin have been in place since 1989.