Warren Treisman was fascinated by the bees he kept in a backyard beehive of his Del Cerro home. The hive rested against a fence on the west side of his backyard, behind a Jacuzzi. Intrigued by his sister’s attempts to keep a hive in a much colder climate back east, Treisman set up his own colony and began harvesting honey.
”Usually, you just watch them and see that the activity is normal and everything’s OK,” Treisman said.
He grew accustomed to the activity the hive brought to his yard.
But a check of the hive in February revealed everything was not normal. He noticed dead bees on the ground. A lot of dead bees.
“It’s just devastating to see all those bees on the ground, dead or dying,” Treisman said.
Thousands of the bees littered the ground near the hive. Occasionally, a bee would stumble out of the hive and fall dying to the ground. Treisman doesn’t know what wiped out the colony because toxicology tests cost about $1,000 for a single bee, but he thinks it is unlikely that parasites or a disease are responsible.
The hive was wiped out quickly and that raised a red flag for University of California San Diego Biological Sciences Researcher James Nieh.
Researchers link common insecticide to bee deaths
“If it was something that occurred within 24 hours where suddenly you had hundreds or even thousands of bees dying. It does suggest there was a chemical basis for it,” Nieh said.
One widely-used insecticide class known as neonicotinoids has been increasingly linked to bee deaths.
Large companies like Syngenta and Bayer began selling products like Merit, Venom and Cruiser in the mid-1990s. They are effective and widely used in agriculture and by consumers.
“We have them in our gardens,” Nieh said.
“They’re used to treat grass. To treat the plants that we plant in our plant beds. They’re in our homes. Some of them are actually used as flea medications for dogs and cats,” Neih said.
The product can be sprayed on plants, injected into the soil or even be used to treat a seed.
“So what you can literally do is put a small amount on a seed. Plant the seed. Water it. It turns into a big plant and every cell in that plant has a tiny amount of that insecticide,” Nieh said.
That means neonicotinoids can live in a neighborhood as long as the treated plant is alive.
And while the dose in each cell is small, thousands of forager bees can pick up the chemical and bring it back to the hive. It can accumulate there until it reaches a critical level.
Fellow UC San Diego Researcher Simone Tosi has worked with Nieh to document the impact of neonicotinoids on bees.
In the lab, he leaned over a small clear box hoping to grab a bee with a pair of tweezers.
“So now is the difficult part in which I need to capture her,” Tosi said.
Tosi has glued a plastic tube onto the bee’s back so he can put the insect on a special harness.
“And then I put the bee like that. This happens. It starts flying,” Tosi said.
The little bee velodrome, which looks a bit like a round hat box, allows researchers to measure speed, strength and endurance while controlling the environment. Controlling the variables is the key.
“Because bees can visit very wide areas around a colony, and you don’t know where is she going. What is she feeding on? And basically, a colony can visit millions of flowers per day,” Tosi said.
Insecticide hurts bees and can kill them
The neonicotinoids are less toxic to bees than what came before, Tosi said, but there are significant sublethal effects. The insecticide can impair flying and hurt the bee’s ability to find the hive. It can also accumulate to toxic levels inside a hive.
“Pesticides do not discriminate between good and bad insects. So they would kill the bad insects, the pests. But they would also kill the bees or cause negative effects on bees. Because those bees eat parts of the plant,” Tosi said.
California Regulators still reviewing
The California Department of Pesticide Regulation began reviewing the insecticide in 2009 after getting a number of reports linked to ornamental plants.
“Does it really affect bees or does it really affect pollinators is the question that we raised,” said Mary Lou Verder Carlos, the chief science advisor and assistant director for the Department of Pesticide Regulation.
Regulators are working with industry and agriculture to determine if usage rules need to be changed.
“We’re thinking may reduce the amounts of pesticides that can be used at certain times. Of course, they still have to be effective, even if you reduce the rates. And then, it could be that they will be strictly applied only at nighttime. Will not be applied during bloom at all,” said Verder Carlos.
State officials will conclude their review of neonicotinoids this summer, more than a decade after deciding that there were enough concerns about these insecticides to look closely at how they are used.
It remains to be seen if the review will change how the chemicals are used, now that there is definitive proof that they hurt bees.
>>> California is still trying to decide how to best regulate powerful insecticides that hit the market back in the 1990s. The chemicals are effective in controlling unwanted pests. There is mounting evidence that they are killing honeybees. KPBS environment reporter Eric Anderson has the details. >> Reporter: Morgan was fascinated by the bees he kept in the back of his home. >> You watch them and see the activity is normal and see every thing is okay. >> Reporter: But in February a test revealed everything was not normal. He noticed a lot of dead bees on the ground. >> It is devastating to see all of these bees on the ground are dead or dying. >> Reporter: Thousands of dead bees were scattered in the backyard. Occasionally B would stumble out of the hive and fall dialing -- dying to the ground. He does not know what wiped out the colony because toxicology test cost $1000 for a single be. The hive was wiped out quickly. That raised a red flag for UCSD biological researcher James die. >> It was something that occurred within 24 hours were suddenly hundreds of thousands of bees died, it suggest a chemical basis. >> Reporter: One Whiteley used pesticide class known as Neil Nick a toy has been increasingly known to cause the deaths. They began selling products like merit and cruiser in the 1990s. They are affect of and widely used in agriculture and by farmers . >> and they are used to treat grass and the plans and they are in our homes. Some are used Desley medications for dogs and cats. >> Reporter: He says the products can be sprayed on plans, injected in soil, or used to treat a seed. >> Put a small amount on the seed, plant the seed, water it, it turns into a big plant, every cell of that plant has a tiny amount of that pesticide. >> Reporter: That means Neil Nick Benoit's the neighborhood as long as the plant is alive. Thousands of forger bee's can pick up the poison and go to the hive. There it can accumulate to a critical level. This doctor has worked with night to document with the insecticide does to bees. He glued a plastic tube unto the bees back so he can put the insect on a special harnessed. >> This is a be flying and he is just flying through the power of their wings and muscles. >> Reporter: That little B looks a bit like a round hack box and allow researchers to measure speed, strength, endurance while controlling the rest of the environment. >> Bees can visit wide areas. We need to know where it's going, what is feeding them, and a colony can visit millions of flowers a day. >> Reporter: He says the Neil Nick gets annoyed's are less toxic to bees than before. He has -- says there are still affects. It can impair flying and hurt the of bee's ability to fly. >> It does not discriminate between a good or bad insect. It will kill the bad insects, but it will also kill the bees or cause negative effects on bees. >> Reporter: A review began in 2009 after getting a number of reports. >> Doesn't really affect bees or pollinators and that is the question that we raised. >> Reporter: Mary Lou Carlos is the chief science advisor and assistant director for the Department of pesticide regulation. Regulators work with industry and agriculture to determine if regulation needs to be determined. >> The pesticide still has to be effective even if you reduce the rate. It could be that they could be strictly applied only at nighttime, or not applied during bloom at all. >> Reporter: State officials will conclude the review this summer more than a decade after deciding if there was enough concerns about these insecticides to look closely at how they are used. Eric Anderson KPBS news.
