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Neonicotinoid insecticide causes bees to abandon their young at night: study

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Spying on bumblebees as they nest has revealed strange behaviour in those exposed to tiny amounts of a widely used pesticide.

Key points for pesticide and bees

Key points

  • Bumblebees exposed to neonicotinoid insecticide spent less time nursing
  • Research adds to the case that widely used pesticide adversely affects bees
  • Native bees could theoretically be at greater risk than honey bees, but experts say more research is needed

A study published in the journal Science found bees exposed to an insecticide called imidacloprid were less likely to feed and care for their larvae, and spent more time hanging out around the edges of the nest.

According to study lead author and Harvard University biologist James Crall, the most surprising and puzzling finding was that the effect on bee behaviour was strongest at night.

“If you look overnight, it’s totally striking,” Dr Crall said.

“Oftentimes the majority or all of a colony [affected by imidaclorprid] will be immobile — which you never see in healthy colonies.

Imidacloprid belongs to a class of insecticides called neonicotinoids (also called “neonics”, which is a lot easier to say).

Chemically similar to nicotine, these are highly effective insecticides that interfere with an insect’s nervous system.

There has been an ongoing and bitter dispute over the evidence that neonic use affects bees badly in the field.

This year the European Union announced it would ban the outdoor use of three insecticides in this class, including imidacloprid.

Bee barcodes

For their study, Dr Crall and team filmed the behaviour of 12 colonies of the Bombus impatiens species of bumblebee in the lab, each for five minutes, 12 times a day for two weeks.

They tracked the movement of the bees by attaching tiny paper tags to their backs, which were marked with a number and a barcode.

“It’s like a really simple QR code,” Dr Crall, who developed the computer tracking software, said.

The bees were allowed to forage in adjacent chambers, some of which contained pesticide-laden nectar.

Separate to their lab study, Dr Crall and team also studied how the pesticide affected colonies in the field.

Normally, bumblebees build an insulating wax “canopy” to keep their brood protected from the cold.

But bees exposed to imidacloprid were less likely to construct canopies compared to their healthy counterparts, and were less able to control the nest’s temperature.

‘Unprecedented detail’ in study

An Australian expert who also studies the impact of neonics on bees said the study provided unprecedented detail.

“This is the first time that we’ve used this method to look at the effect of a compound like this inside the colony on brood rearing,” Andrew Barron of Macquarie University — and who was not involved in the new research — said.

He said the level of pesticide used in the study was tiny — about 10 parts per billion.

While the new study is in bumblebees, Dr Barron said it was “not unreasonable” to assume there are similar effects in other bee species.

“In terms of the neurobiology of bees and brain structures, they’re all really quite similar,” Dr Barron said.

And, he said, the consequences of bees spending less time caring for their young would be lower larval survival and slower colony growth.

“That would line up with what we’ve seen with pesticide impacts on both honey bees and bumblebees.”

Evidence of how neonics affect bees is complex, not least because the same dose of pesticide can have different effects on the same species depending on their location.

But Dr Barron said this just suggests the effects of pesticide involves interaction with other factors such as the local environment.

He emphasised the majority of studies have shown low doses have adverse effects on bee behaviour, including their ability to forage.

Bees under threat?

Apart from pesticides and other pollutants, bees around the world face a multitude of environmental risks, which include diseases such as those caused by the varroa mite as well as lack of food.

According to authorities, Australian honey bee populations are not in decline.

But the same cannot be said of our native bees, according to University of Adelaide bee behaviour expert Katja Hogendoorn, who was not involved with the study.

Native bees also play an important role in pollination — in crops as well as native plants.

Dr Hogendoorn said there is little research on our native bees, so we don’t know whether numbers are increasing or decreasing.

But Dr Hogendoorn also said studies in the US and Europe have shown native bee populations have halved. Similar figures are likely in agricultural areas in Australia due to the removal of native vegetation, as well as pesticide use.

Over half of native bee species don’t forage on introduced plants, which means native bees in agricultural areas are at risk of malnutrition, Dr Hogendoorn said.

And while beekeepers can move their honey bee hives to avoid pesticide exposure, unmanaged native bees that nest in trees are more vulnerable.

“Native bees forage about 300 metres around their nest, so unlike honey bees, they cannot dilute the effects of pesticides by foraging far and wide,” Dr Hogendoorn said.

Nigel Raine of the University of Guelph in Canada points to another reason why native bees may be at greater risk.

While bumblebees and honey bees live in colonies, the effects described in the new study could be more severe in what are known as “solitary” bees, he wrote in a commentary also published in Science.

Solitary bees make up the majority of the 20,000 bee species in the world, and most of Australia’s native bee species.

In solitary bees, Dr Raine wrote, females are “overworked single mothers”, solely responsible for raising their brood.

This would make it “more likely that a small behavioural change as a result of pesticide exposure might have a measurable impact on their ability to produce as many high quality offspring”.

Where to now for neonics?

Despite concern by beekeepers and others in Australia, the Australian Pesticides and Veterinary Medicines Authority (APVMA) has no plans to review the insecticide’s use in the wake of the European ban decision.

“Given that Australian honey bee health is good, there is no cause for similar restrictions here,” the regulator states on its website, although it will continue to monitor the issue.

The APVMA also states that the National Residue Survey, which tests animal and plant products, has found no traces of neonics in any honey products tested.

But Dr Barron says his own research with CSIRO has found negative impacts on bees from neonics at just five parts per billion.

This is well below the 10 parts per billion level tested for by the National Residue Survey.

Like Dr Barron, Dr Hogendoorn argued that more judicious use of neonics is in order.

“Neonics are a very useful tool and in many cases better than other things, but they need to be used very carefully,” she said.

Dr Barron said if a pesticide is banned and replaced with another insecticide, it’s not necessarily going to be a better situation.

While not calling for an agricultural ban, Dr Hogendoorn said such insecticides should be avoided in home gardens.

This year Australian retailers announced they would voluntarily withdraw sale of the neonic-containing Confidor to home gardeners.

The manufacturer of Confidor refers to the APVMA website, which states neonics-based products are “safe when used according to the label directions”.

But Dr Hogendoorn said we need the results on specific research on the impact of neonics use, also in combination with other pesticides, in the Australian environment.

She added it is also important to look at the impact of such pesticides on other beneficial organisms in the environment, which feed on pests and reduce the need to spray in the first place.

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Researchers walk back major ocean warming result

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Scripps Pier after sunset in La Jolla, California. Image via Hayne Palmour IV/ San Diego Union-Tribune/ os Angeles Times.http://www.latimes.com/science/sciencenow/la-sci-sn-oceans-heat-error-20181114-story.html

This is good news. It is less certain today that Earth’s oceans are 60% warmer than we thought (although they may still be that warm). As reported in the Los Angeles Times today (November 14, 2018), researchers with UC San Diego’s Scripps Institution of Oceanography and Princeton University have had to walk back a widely reported scientific result – based on a paper published in Nature last month – showing that showed Earth’s oceans were heating up dramatically faster than previously thought, as a result of climate change.

The October 31 paper in Nature stated the oceans had warmed 60% more than outlined by the United Nations’ Intergovernmental Panel on Climate Change (IPCC). On November 6, mathematician Nic Lewis posted his criticisms of the paper at Judith Curry’s blog. Both Lewis and Curry are critics of the scientific consensus that global warming is ongoing and human-caused.

In his November 6 blog post, Lewis pointed out flaws in the October 31 paper. The authors of the October 31 paper now say they’ve redone their calculations, and – although they find the ocean is still likely warmer than the estimate used by the IPCC – they agree that they “miffed” the range of probability. They can no longer support the earlier statement of a heat increase 60% greater than indicated. They now say there is a larger range of probability, between 10% and 70%, as other studies have already found.

A correction has been submitted to Nature.

The Los Angeles Times reported that one of the co-author’s on the paper – Ralph Keeling at the Scripps Institution of Oceanography – “took full blame” and thanked Lewis for alerting him to the mistake. Keeling told the Los Angeles Times:

When we were confronted with his insight it became immediately clear there was an issue there. We’re grateful to have it be pointed out quickly so that we could correct it quickly.

In the meantime, the Twitter-verse today has done the expected in a situation like this, where a widely reported and dramatic climate result has had to be walked back. Many are making comments like this one:

But cooler heads on Twitter and elsewhere in the media are also weighing in, pointing out – as has been necessary to point out time and again – that science is not a “body of facts.” Science is a process. Part of the reason scientists publish is so that other scientists can find errors in their work, so that the errors can be corrected.

All scientists know this. The Los Angeles Times explained it this way:

While papers are peer-reviewed before they’re published, new findings must always be reproduced before gaining widespread acceptance throughout the scientific community …

The Times quoted Gerald Meehl, a climate scientist at the National Center for Atmospheric Research in Boulder, Colorado, as saying:

This is how the process works. Every paper that comes out is not bulletproof or infallible. If it doesn’t stand up under scrutiny, you review the findings.

Bottom line: An error has been found in the October 31, 2018 paper published in Nature – showing an increase in ocean warming 60% greater than that estimated by the IPCC. The authors have acknowledged the error, and a correction has been submitted to Nature.

October 31 paper in Nature: Quantification of ocean heat uptake from changes in atmospheric O2 and CO2 composition

November 6 blog post by Nic Lewis: A major problem with the Resplandy et al. ocean heat uptake paper

Deborah Byrd

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Upsettingly Large Fungus in Michigan Weighs 440 Tons and Is 2500 Years Old

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  1. Upsettingly Large Fungus in Michigan Weighs 440 Tons and Is 2500 Years Old  Gizmodo
  2. Could this giant 2500-year-old fungus hold the cure to cancer?  Mother Nature Network
  3. Full coverage



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NASA wants Canadian boots on the moon but feds still pondering space options

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OTTAWA — The Trudeau government faced criticism Wednesday for a tepid response to the head of the U.S. space agency saying he wants to see Canadian astronauts walking on the moon in the near future.

Jim Bridenstine, the administrator of he National Aeronautics and Space Administration, said a reconstituted lunar program is the first step toward deeper space exploration, including a mission to Mars.

On a two-day trip to Ottawa, the NASA chief made an impassioned pitch for Canada to continue its decades-long space partnership with the U.S., including by supplying astronauts.

NASA is embarking on the creation of its new Lunar Gateway, a space station it is planning to send into orbit around the moon starting in 2021. The agency wants to create a “sustainable lunar architecture” that would allow people and equipment to go back and forth to the moon regularly, Bridenstine said.

“If Canadians want to be involved in missions to the surface of the moon with astronauts, we welcome that. We want to see that day materialize,” he told a small group of journalists in Ottawa ahead of his keynote speech to the Aerospace Industries Association of Canada.

“We think it would be fantastic for the world to see people on the surface of the moon that are not just wearing the American flag, but wearing the flags of other nations.”

The U.S. is seeking broad international support for its new lunar initiative, Bridenstine told the industry conference. He said NASA wants Canada’s expertise in artificial intelligence and robotics, which could include a next-generation Canadarm on the Lunar Gateway and more Canadian technology inside.

Innovation Minister Navdeep Bains, a vocal booster of Canada’s AI hubs in Ontario and Quebec, said the government is committed to sustaining its partnership with NASA, but he had no specifics.

The minister said the government is still working on a long-awaited space policy that has many dimensions and will be made public before next fall’s federal election.

“At this stage, we would not take anything off the table,” Bains told reporters, when on pressed on the possibility of contributing astronauts to moon missions. “We demonstrated very clearly we want to work with NASA. We want to work with other allies as well.”

The head of one leading Canadian space technology firm said he and many other business leaders at the conference were surprised by the government’s apparent lack of enthusiasm for Bridenstine’s ambitious request.

“There was a lot of excitement about the opportunity that was clearly being given to Canada here,” Mike Greenley, the president of MDA, said in an interview. “I’m a little bit concerned about that lack of response.”

MDA makes sensors, robots and components for satellites.

Greenley said it is possible the government is still considering its options, but given the urgency of the U.S. timetable, that might not be wise.

“The concern would be if we wait too long we can miss the opportunity,” he said. “We best not ponder this too long.”

Greenley said he’d like to see Canadian astronauts on the moon one day, but to get to that stage Canada needs to participate in NASA’s broader lunar program.

Bridenstine said the return to the moon is a stepping stone to a much more ambitious goal: exploration that could include reaching Mars in the next two decades.

“The moon is, in essence, a proving ground for deeper space exploration,” he said.

Marc Garneau, who was the first Canadian to reach outer space in 1984 and is now Canada’s transport minister, told the conference he wants Canada to continue being a “star player” in all fields of the aerospace industry. But he had no new space initiatives to announce.

On Dec. 3, Canadian astronaut David Saint-Jacques will travel to the International Space Station on his first mission.

Mike Blanchfield, The Canadian Press


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