My assessment of the current state of UK bees follows

MPs call for precautionary ban on pesticides linked to bee decline

Pressure on the government to impose a “precautionary moratorium” on three controversial pesticides linked to the decline of bee populations will crank up a notch today, with the publication of a new report from the Environmental Audit Committee (EAC) criticising ministers for their “extraordinarily complacent approach to protecting bees”.

The report calls on the government to impose a ban on imidacloprid, clothianidin and TMX, suspending their use on flowering crops attractive to pollinators. It also argues that with several of the UK’s largest garden retailers, including B&Q and Homebase, having voluntarily withdrawn neonicotinoids their shelves the government should impose a full ban on the sale of neonicotinoids for public domestic use, in order to create an “urban safe haven for pollinators”.

The report notes that France, Germany, Italy and Slovenia have already imposed partial bans on some neonicotinoids and criticises the government for opposing European Commission proposals for a full moratorium on imidacloprid, clothianidin and TMX on all crops attractive to bees.

“Defra seems to be taking an extraordinarily complacent approach to protecting bees given the vital free service that pollinators provide to our economy,” said EAC chair Joan Walley in a statement. “If farmers had to pollinate fruit and vegetables without the help of insects it would cost hundreds of millions of pounds and we would all be stung by rising food prices. Defra Ministers have refused to back EU efforts to protect pollinators and can’t even come up with a convincing plan to encourage bee-friendly farming in the UK.”

Environment Secretary Owen Paterson has argued that the benefits of any ban would outweigh the costs, [a mistake in editing?] insisting there is not yet sufficient evidence to impose restrictions on pesticides that are widely used across the agricultural industry.

But Walley confirmed that the EAC had reached an entirely different conclusion. “We believe that the weight of scientific evidence now warrants precautionary action, so we are calling for a moratorium on pesticides linked to bee decline to be introduced by 1 January next year,” she said. “This allows farmers to use treated seeds that have already been purchased for this growing season and gives Defra time to implement EU legislation on the sustainable use of pesticides.”

The report also criticises the behaviour of some chemicals companies, which have argued that there is not sufficient evidence of a link between the pesticides and declines in bee populations to justify a ban, but have failed to disclose full results from their research into the impact of the chemicals.

“Pesticide companies often try to pick holes in studies linking their products to bee decline, but when pushed to publish their own research and safety studies they hide behind claims of commercial sensitivity,” said Walley. “The industry must open itself to greater academic scrutiny if it wants to justify its continued opposition to the precautionary protection of pollinators.”

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Neonicotinoid pesticides are shown to poison bees. While this study was concerned with bumblebees it is likely that the findings are also relevant to honeybees and similar insects.

The point about pesticides is that they are poisons. Neonicotinoid pesticides are systemic pesticides that affect the whole plant including nectar and pollen.

Insecticide blamed for bee deaths by Stirling University study

Use of a specific group of insecticides is having a serious impact on bumblebee populations, according to a team of Scottish scientists.

The Stirling University researchers found exposure even to low levels of neonicotinoid pesticides had a serious impact on the health of bumblebees.

Bee populations have fallen sharply, and scientists say urgent action is needed to reverse the decline.

Of particular concern is an 85% drop in the number of queens.

That means 85% fewer nests in the following year.

The research found bumblebee colony growth slowed after exposure to the chemicals.

This may partly be to blame for colony collapse disorder, a mysterious phenomenon which has hit large numbers of hives in Europe and North America in recent years.

Professor Dave Goulson, who led the Stirling research, said: “Some bumblebee species have declined hugely. For example in North America, several bumblebee species which used to be common have more or less disappeared from the entire continent. In the UK, three species have gone extinct.

“Bumblebees pollinate many of our crops and wild flowers. The use of neonicotinoid pesticides on flowering crops clearly poses a threat to their health, and urgently needs to be re-evaluated.”

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I am uncertain about the claim to be the first research “to demonstrate the sub-lethal effects of pesticide residue exposure on honey bees” – I believe that there may be a growing body of research that demonstrates this.

Research expands understanding of bee health

Recently published research is the first to demonstrate the sub-lethal effects of pesticide residue exposure on honey bees, which play a critical role in the production of one third of the food that human’s consume.

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The pesticides involved in Wu’s study include those used by beekeepers, growers and homeowners. They include miticides, insecticides, fungicides and herbicides. The accumulation occurs because beekeepers reuse combs to save on the expense of replacement.

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Some of the consequences to honey bees that Wu found were delayed larval development and a shortened adult lifespan, which can result indirectly in premature shifts in hive roles and foraging activity.

Shortened bee lifespans dramatically change the dynamic of a hive. According to Sheppard, foragers are the bees that provide pollination and bring food back to a hive.

“A bee’s life span as a forager is on average only the last eight days of its life,” he said. “This research shows that, if raised with pesticide residues in the brood comb, an individual’s foraging life span is shortened by four days, a 50 percent cut.”

If there are not sufficient foragers, the colony makes up the deficit by using younger bees that are not physiologically ready. The result is a negative cascade through the hive all the way down to the larval bees because individual nurse bees must prematurely move toward foraging behavior and stop feeding larvae, Sheppard said.