bees

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Bees: Continuing decline a big concern for global food security

A new study by scientists from three countries underlines how dependant our crops are on healthy bee populations.

bees

Image via Adobe Stock

The decline in the world’s bee population may have serious ramifications for global food security, says a new study published on Wednesday 29 July by the London-based Royal Society.

Conducted by Canadian, Swedish and US scientists who studied 131 crop fields in the US, it found that this could have serious implications as farming becomes increasingly more intensive in an effort to churn out greater volumes to feed the world’s growing population.

Trends are setting us up for problems

“The trends we are seeing now are setting us up for food security problems,” said Rachael Winfree, an ecologist and pollination expert who was a senior author of the paper.

“We aren’t yet in a complete crisis… but the trends aren’t going in the right direction. Our study shows this isn’t a problem for 10 or 20 years from now – it’s happening right now.”

According to the researchers, three-quarters of the world’s food crops that are dependent upon pollinators could falter due to a lack of bees.

Five out of seven crops are being impeded

Of the seven different crops covered by the research, five produced evidence that a reduced number of bees is impeding the volume of food that can be grown – something the researchers called “pollinator limitation”.

Among the crops that are not able to produce as effectively as they should are cherries, blueberries and apples.

“The crops that got more bees got significantly more crop production,” noted Winfree. She added:  “I was surprised; I didn’t expect they would be limited to this extent.”

One wild bee species is down by 87%

The study points out that the numbers of wild bees, such as bumble bees, are being reduced by factors like loss of habitat, use of toxic pesticides and climatic changes.

One species of wild bee, the Rusty Patched Bumble Bee, has declined 87% in 20 years and was the first bee to be placed on the US endangered species list in 2017.

The US Fish & Wildlife Service says the species “once occupied grasslands and tallgrass prairies of the Upper Midwest and Northeast, but most grasslands and prairies have been lost, degraded, or fragmented by conversion to other uses”.

Captive bee population suffering from disease

Managed honeybees – those that are kept by bee keepers – are suffering from disease and their numbers are also less than optimal.

The study says a significant proportion of American agriculture is being propped up by honey bees which are “frantically replicated and shifted around the country in hives in order to meet a growing need for crop pollination”.

It adds: “Almonds, one of the two crops not shown to be suffering from a lack of bees in the study, are mostly grown in California, where most of the beehives in the US are trucked to each year for a massive almond pollination event.”

The current system is unsustainable long term

Winfree warns that this may be unsustainable as honey bee colonies are weaker than they used to be and wild colonies declining.

“The agriculture is getting more intensive and there are fewer bees, so at some point the pollination will become limited. Even if honeybees were healthy, it’s risky to rely so much on a single bee species. It’s predictable that parasites will target the one species we have in these monocultural crop fields,” she says.

“Our findings show that pollinator declines could translate directly into decreased yields or production for most of the crops studied, and that wild species contribute substantially to pollination of most study crops in major crop-producing regions.”

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