Bees: How Important Are They and What Would Happen If They Were Extinct?

The Conversation - I Need to Know August 19, 2019

How important are bees and what will happen when they go extinct? Is there research into what is killing them? I’ve been told it’s weed killers… – Tink, aged 18, Cornwall, UK.

Bees – including honey bees, bumble bees and solitary bees – are very important because they pollinate food crops. Pollination is where insects move pollen from one plant to another, fertilising the plants so that they can produce fruit, vegetables, seeds and so on. If all the bees went extinct, it would destroy the delicate balance of the Earth’s ecosystem and affect global food supplies.

There are more than 800 wild bee species within Europe, seven of which are classified by the International Union for Conservation of Nature (IUCN) as critically endangered. A further 46 are endangered, 24 are vulnerable and 101 are near threatened. While it’s unlikely that all bee species will be wiped out anytime soon, losing these threatened species would still have a big impact on pollination around the world, wiping out plant species, some of which we rely on for our food.


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But the problem goes far beyond bees. In fact, honeybees are responsible for only one third of crop pollination and a very small proportion of the wild plant pollination. There are a diverse range of other insects including butterflies, bumblebees and small flies that do the rest of the work – and it looks like these insects are in trouble too.

A bumblebee, pulling it’s weight. Emily L Brown, Author provided

A bumblebee, pulling it’s weight. Emily L Brown, Author provided

A recent study suggests that as many as 40% of the world’s insect species are in decline. Insects are facing extinction rates that are eight times higher than vertebrates. In Germany, scientists have recorded losses of up to 75% of the total mass of insects in protected areas.

These trends lead scientists to believe that about a third of all insect species – that’s nearly 2m – may be threatened with extinction. And that figure is growing by over 100,000 species every year. Yet hard data on threatened insect species is lacking, with only 8,000 records actually assessed by the IUCN.

Here’s a rundown of what scientists believe to be the top causes of declines in insect diversity and abundance.

Invasive species

Invasive predators, parasites and disease-causing bacteria called “pathogens” have been blamed for the collapse of honeybee colonies around the world.

Recently, the spread of the Asian Hornet in Europe has caused great concern. This species preys on honey bees, and a single hornet is capable of killing an entire hive.

There is some evidence that wild bees in North America have declined in the face of fungal and bacterial diseases.



Of course, in the past bees have coexisted with these pathogens. The fact that scientists have seen more bees lost to these diseases in recent times is probably linked with the bees’ increased exposure to pesticides, which can damage their immune systems.

Pesticides

Pollution – particularly from exposure to pesticides – is a key cause of pollinator decline. There are three types of chemical pesticide widely used in the UK: insecticides targeting insect pests, fungicides targeting fungal pathogens of crops and herbicides targeting weeds.

Insecticides contain chemicals that can kill pollinators, so they’re clearly a threat. But they may not be the greatest problem pollinators experience. Herbicides are actually used five times as much in farming as insecticides. These weed killers target a huge variety of the wild plants that bees need to forage.

Environmentally-friendly farming schemes recommend planting wildflower strips on the edge of crops, to provide safe refuge and food sources for pollinators. Yet drifting clouds of herbicide from growing fields can contaminate these wildflower strips.

Wildflowers border farmland in Sussex, UK.  Shutterstock.

Wildflowers border farmland in Sussex, UK. Shutterstock.

The most cutting-edge research suggests glyphosate (the most commonly used weed killer) can impact the gut microbes of bees, which can have devastating implications for their health.

Although exposure to herbicides and pesticides used by farmers is likely to be one of the main causes of pollinator decline, the chemicals used by city authorities and civilian gardeners might also be harming bees and other insects. So, for the bees’ sake, it’s best to avoid using them where possible.

Climate change

Global warming is believed to be a major driver of wild bee declines. Some wild bees can only survive in a narrow range of temperatures. As their habitats get warmer, the places where they can live grow smaller. For example, some might be forced to live at higher altitudes, where it’s cooler, reducing the space they have to live in.

Habitat destruction

The way land is farmed has been associated with declines in biodiversity and pollination. Farming destroys the kinds of spaces that bees use to nest, it takes away the diversity of food that bees use to forage on and it even has wider impacts on other animals like wild birds, mammals and amphibians.

While countless insect species are currently going extinct, those that remain are taking their place, so it’s unlikely that crops will stop being pollinated any time soon. Generalist species such as the buff-tailed bumblebee, the European honey bee and common small black flies, which can survive in a huge range of temperatures and conditions, will become the main species pollinating our food sources, while rarer, more specialist species will decline.

But as generalist species move in to take the place space left by the losses of specialists, and complex ecosystems become dominated by a couple of generalists, the whole system becomes far more susceptible to a single sudden change. Insects form the base of many intricate food webs, their decline will result in a complex cascade of impacts on vertebrates, threatening ecological stability.

https://theconversation.com/bees-how-important-are-they-and-what-would-happen-if-they-went-extinct-121272

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Agriculture’s Increasing Dependence On Pollination, Coupled With A Lack Of Crop Diversity, May Threaten Food Security And Stability

Catch the Buzz By Alan Harman August 12, 2019

agriculture.jpg

New research suggests global trends in farming practices are undermining the pollinators that crops depend on and putting agricultural productivity and stability at risk,

An international team of researchers has identified countries where agriculture’s increasing dependence on pollination, coupled with a lack of crop diversity, may threaten food security and economic stability.

The study, published in the journal Global Change Biology, is the first global assessment of the relationship between trends in crop diversity and agricultural dependence on pollinators.

Using annual data from the U.N. Food and Agriculture Organization from 1961 to 2016, the study showed that the global area cultivated in crops that require pollination by bees and other insects expanded by 137%, while crop diversity increased by just 20.5%.

This imbalance is a problem, the researchers say, because agriculture dominated by just one or two types of crops only provides nutrition for pollinators during a limited window when the crops are blooming.

Maintaining agricultural diversity by cultivating a variety of crops that bloom at different times provides a more stable source of food and habitat for pollinators.

“This work should sound an alarm for policymakers who need to think about how they are going to protect and foster pollinator populations that can support the growing need for the services they provide to crops that require pollination,” said David Inouye, professor emeritus of biology at the University of Maryland and a co-author of the research paper.

Globally, a large portion of the total agricultural expansion and increase in pollinator dependence between 1961 and 2016 resulted from increases in large-scale farming of soybean, canola and palm crops for oil.

The researchers expressed concern over the increase in these crops because it indicates a rapid expansion of industrial farming, which is associated with environmentally damaging practices such as large monocultures and pesticide use that threaten pollinators and can undermine productivity.

Particularly vulnerable to potential agricultural instability are Brazil, Argentina, Paraguay and Bolivia, where expansion of pollinator-dependent soybean farms has driven deforestation and replaced rich biodiversity that supports healthy populations of pollinators with large-scale single-crop agriculture (monoculture).

Malaysia and Indonesia face a similar scenario from the expansion of oil palm farming.

“Farmers are growing more crops that require pollination, such as fruits, nuts and oil seeds, because there’s an increasing demand for them and they have a higher market value,” Inouye says.

“This study points out that these current trends are not great for pollinators, and countries that diversify their agricultural crops are going to benefit more than those that expand with only a limited subset of crops.”

In Europe, farmland is contracting as development replaces agriculture, but pollinator-dependent crops are replacing non-pollinator-dependent crops such as rice and wheat (which are wind pollinated).

The study says increasing need for pollination services without parallel increases in diversity puts agricultural stability at risk in places such as Australia, the United Kingdom, Germany, France, Austria, Denmark and Finland.

In the U.S., agricultural diversity has not kept pace with expansion of industrial-scale soybean farming.

“This work shows that you really need to look at this issue country by country and region by region to see what’s happening because there are different underlying risks,” Inouye says..

“The bottom line is that if you’re increasing pollinator crops, you also need to diversify crops and implement pollinator-friendly management.”

https://www.beeculture.com/catch-the-buzz-agricultures-increasing-dependence-on-pollination-coupled-with-a-lack-of-crop-diversity-may-threaten-food-security-and-stability/

Our 'Bee-Eye Camera' Helps Us Support Bees, Grow Food And Protect The Environment

To help draw bees’ attention, flowers that are pollinated by bees have typically evolved to send very strong colour signals. Credit:  Shutterstock

To help draw bees’ attention, flowers that are pollinated by bees have typically evolved to send very strong colour signals. Credit: Shutterstock

Walking through our gardens in Australia, we may not realise that buzzing around us is one of our greatest natural resources. Bees are responsible for pollinating about a third of food for human consumption, and data on crop production suggests that bees contribute more than US$235 billion to the global economy each year.

By pollinating native and non-native plants, including many ornamental species, honeybees and Australian native bees also play an essential role in creating healthy communities – from urban parks to backyard gardens.

Despite their importance to human and environmental health, it is amazing how little we know how about our hard working insect friends actually see the world.

By learning how bees see and make decisions, it's possible to improve our understanding of how best to work with bees to manage our essential resources.

How bee vision differs from human vision

A new documentary on ABC TV, The Great Australian Bee Challenge, is teaching everyday Australians all about bees. In it, we conducted an experiment to demonstrate how bees use their amazing eyes to find complex shapes in flowers, or even human faces.

Humans use the lens in our eye to focus light onto our retina, resulting in a sharp image. By contrast, insects like bees use a compound eye that is made up of many light-guiding tubes called ommatidia.

Insects in the city: a honeybee forages in the heart of Sydney. Credit: Adrian Dyer/RMIT University

Insects in the city: a honeybee forages in the heart of Sydney. Credit: Adrian Dyer/RMIT University

The top of each ommatidia is called a facet. In each of a bees' two compound eyes, there are about 5000 different ommatidia, each funnelling part of the scene towards specialised sensors to enable visual perception by the bee brain.

Since each ommatidia carries limited information about a scene due to the physics of light, the resulting composite image is relatively "grainy" compared to human vision. The problem of reduced visual sharpness poses a challenge for bees trying to find flowers at a distance.

To help draw bees' attention, flowers that are pollinated by bees have typically evolved to send very strong colour signals. We may find them beautiful, but flowers haven't evolved for our eyes. In fact, the strongest signals appeal to a bee's ability to perceive mixtures of ultraviolet, blue and green light.

Building a bee eye camera

Despite all of our research, it can still be hard to imagine how a bee sees.

How we see fine detail with our eyes, and how a bee eye camera views the same information at a distance of about 15cm. Credit: Sue Williams and Adrian Dyer/RMIT University

How we see fine detail with our eyes, and how a bee eye camera views the same information at a distance of about 15cm. Credit: Sue Williams and Adrian Dyer/RMIT University

So to help people (including ourselves) visualise what the world looks like to a bee, we built a special, bio-inspired "bee-eye" camera that mimics the optical principles of the bee compound eye by using about 5000 drinking straws. Each straw views just one part of a scene, but the array of straws allows all parts of the scene to be projected onto a piece of tracing paper.

The resulting image can then be captured using a digital camera. This project can be constructed by school age children, and easily be assembled multiple times to enable insights into how bees see our world.

Because bees can be trained to learn visual targets, we know that our device does a good job of mimicking a bees visual acuity.

Student projects can explore the interesting nexus between science, photography and art to show how bees see different things, like carrots – which are an important part of our diet and which require bees for the efficient production of seeds.

Yellow flower (Gelsemium sempervirens) as it appears to our eye, as taken through a UV sensitive camera, and how it likely appears to a bee. Credit: Sue Williams and Adrian Dyer/RMIT University

Yellow flower (Gelsemium sempervirens) as it appears to our eye, as taken through a UV sensitive camera, and how it likely appears to a bee. Credit: Sue Williams and Adrian Dyer/RMIT University

Understanding bee vision helps us protect bees

Bees need flowers to live, and we need bees to pollinate our crops. Understanding bee vision can help us better support our buzzy friends and the critical pollination services they provide.

In nature, it appears that flowers often bloom in communities, using combined cues like colour and scent to help important pollinators find the area with the best resources.

Having lots of flowers blooming together attracts pollinators in much the same way that boxing day sales attract consumers to a shopping centre. Shops are better together, even though they are in competition – the same may be true for flowers!

This suggests that there is unlikely to be one flower that is "best" for bees. The solution for better supporting bees is to incorporate as many flowers as possible – both native and non native – in the environment. Basically: if you plant it, they will come.

We are only starting to understand how bees see and perceive our shared world – including art styles – and the more we know, the better we can protect and encourage our essential insect partners.

How a bee eye camera works by only passing the constructive rays of light to form an image. Credit: Sue Williams and Adrian Dyer/RMIT University

How a bee eye camera works by only passing the constructive rays of light to form an image. Credit: Sue Williams and Adrian Dyer/RMIT University

Clip from “The Great Australian Bee Challenge, Episode 2.

Looking at the fruits and vegetables of bee pollination; a bee camera eye view of carrots. Credit: Sue Williams and Adrian Dyer/RMIT University

Looking at the fruits and vegetables of bee pollination; a bee camera eye view of carrots. Credit: Sue Williams and Adrian Dyer/RMIT University

Shedding New Light on Honey Bee Chromosomes

Bug Squad Author: Kathy Keatley Garvey Published on: December 3, 2018

Honey bee, Apis mellifera. (Photo by Kathy Keatley Garvey)

Honey bee, Apis mellifera. (Photo by Kathy Keatley Garvey)

Honey bee geneticists with long ties to UC Davis are putting together those missing pieces of the puzzle involving bee chromosomes.

Newly published research by a team of Germany-based honey bee geneticists, collaborating with Robert Eugene (“Rob”) Page Jr., of Arizona State University/University of California, Davis, offers new insights in the ability to modify and study the chromosomes of honey bees.

Martin Beye, a professor at the University of Düsseldorf, Germany and a former postdoctoral fellow in Page's lab at UC Davis, served as the lead author of the research, “Improving Genetic Transformation Rates in Honeybees,” published in Scientific Reports in the journal Nature.

The researchers accomplished the work in Beye's lab in Germany and the Page labs.

“The significance of this paper lies in the ability to modify the chromosomes of honey bees and study the effects of individual genes,” said Page, former professor and chair of the UC Davis entomology department before capping his academic career as the Arizona State University provost.

“The honey bee genome,” Page explained, “is composed of about 15,000 genes, each of which operates within a complex network of genes, doing its small, or large, share of work in building the bee, keeping its internal functions operating, or helping it function and behave in its environment. The ability to transform, change, genes, or add or delete genes from chromosomes of bees, has been exceptionally challenging and the effort spans decades. Martin tackles problems such as this. He takes on the most challenging genetic problems and solves them.”

Beye was the first to map the major sex-determining gene for honey bees, considered one of the most important papers ever published on honey bee genetics. He “then moved on and developed a way to implement gene editing, being able to alter single genes within the genome,” Page related. “Now he has developed a method to introduce new genetic material into the honey bee.”

In their abstract, the six-member team wrote that “Functional genetic studies in honeybees have been limited by transformation tools that lead to a high rate of transposon integration into the germline of the queens. A high transformation rate is required to reduce screening efforts because each treated queen needs to be maintained in a separate honeybee colony. Here, we report on further improvement of the transformation rate in honeybees by using a combination of different procedures.”

Specifically, the geneticists employed a hyperactive transposase protein (hyPBaseapis), tripling the amount of injected transposase mRNAs. They injected embryos into the first third (anterior part) of the embryo. These three improvements together doubled the transformation rate from 19 percent to 44 percent.

“We propose that the hyperactive transposase (hyPBaseapis) and the other steps used may also help to improve the transformation rates in other species in which screening and crossing procedures are laborious,” they wrote in their abstract.

For their research, the scientists chose feral Carniolan or carnica colonies. Carniolans, a darker bee, are a subspecies of the Western honey bee, Apis mellifera.

Beye joined the Page lab in 1999 as the recipient of a Feodor Lynen Research Fellowship, an award given to the brightest young German Ph.Ds to provide an opportunity for them to work in the laboratories of U.S. recipients of the Alexander von Humboldt Research Prize. Page, who won the Humboldt Prize in 1995, continues to focus his research on honey bee behavior and population genetics, particularly the evolution of complex social behavior.

Following his postdoctoral fellowship, Beye returned to the Page labs at UC Davis and ASU as a visiting scientist. (link to https://www.ucdavis.edu/news/honeybee-gene-find-ends-150-year-search ) Beye spoke at UC Davis this spring as part of his Humboldt-funded mini sabbatical, the guest of Page and hosted by the Department of Entomology and Nematology. During his visit, he and UC Davis bee scientist Brian Johnson developed collaborative projects that they will begin in the spring of 2019. “This is exactly what the Alexander von Humboldt foundation wants – to build and extend interactive networks of researchers,” Page commented.

About Robert Page Jr.
Noted honey bee geneticist Robert Page Jr., author of The Spirit of the Hive: The Mechanisms of Social Evolution, published by Harvard University Press in 2013, recently received the Thomas and Nina Leigh Distinguished Alumni Award, UC Davis Department of Entomology and Nematology.

Page received his doctorate in entomology from UC Davis and served as a professor and chair of the UC Davis entomology department before capping his academic career as the Arizona State University (ASU) provost. He maintained a honey bee breeding program managed by bee breeder-geneticist Kim Fondrk at the Harry H. Laidlaw Jr. Honey Bee Research Facility, UC Davis, for 24 years, from 1989 to 2015.

Now provost emeritus of ASU and Regents Professor since 2015, he continues his research, teaching and public service in both Arizona and California and has residences in both states. He plans to move to California in December.

Page focuses his research on honey bee behavior and population genetics, particularly the evolution of complex social behavior. One of his most salient contributions to science was to construct the first genomic map of the honey bee, which sparked a variety of pioneering contributions not only to insect biology but to genetics at large.

Resources:

UC Davis Behind the Groundbreaking Discovery of Honey Bee Sex Determination

About Robert E. Page Jr., Recipient of UC Davis Alumni Award

Here's Hope for the Bees: A Manifesto

GreenBiz.com   By Richard Crespin   September 29, 2014

We need bees. As a beekeeper, an entomologist, a conservationist, an agribusiness scientist and a consultant, we humbly acknowledge that our jobs depend on them. As do much of your diet and our economy.

Bees are big business. The real economic value of bees comes from more than honey: it comes from pollination.

By some estimates, one-third of global food production relies on pollinators. Honey bees and other insects pollinate 80 percent of flowering plants — including almonds, apples, broccoli, strawberries and alfalfa for beef and dairy cattle.

According to the United States Department of Agriculture, honey bees support $18 billion of America’s annual agriculture production. In economic terms, bees provide more value than chicken and come in below only cattle and pigs. Secretary of Agriculture Tom Vilsack got it right: “The future of America’s food supply depends on healthy honey bees.”

The news is filled with stories about declining bee health — even the potential collapse of bee populations altogether. The impact goes way beyond the beehive. Whole supply chains are at risk: big sections of the grocery store, entire menu categories at restaurants and significant numbers of consumer goods either go away or become a lot harder to produce.

For that reason, many of my peers and I have come together to form a new Honey Bee Health Coalition. Comprehensive solutions are out there, and we are dedicated to accelerating them. But we need your help.

The Beekeeper: Randy Verhoek of the American Honey Producers Association

"I can tell you that running honey bees has gotten a lot harder. I’ve worked with bees most of my life, and I’ve seen their decline firsthand. The tough part, though, is it’s not just one thing, it’s a bunch of things making bees sick. And it will take a bunch of us — beekeepers, growers, crop producers, ag companies, food companies, government agencies, conservationists, scientists, academics, and more — to make things better. To make sure that happens, as president of the American Honey Producers Association, I helped launch the HBHC in June during National Pollinator Week."

 

The Entomologist: Dennis van Engelsdorp of the University of Maryland

"When we first investigated reports of extreme colony losses in the winter of 2006-2007, I and other entomologists thought determining the cause would be simple: a new virus, a pesticide or some other single issue. That was naïve. Honey bees and other pollinators face complex problems. Evidence suggests that disease and parasite management, farm practices, government policies, pesticide registration and use, landscape and climate all contribute to colony losses. A multi-causal problem requires a multi-pronged solution. And that’s why I, and many others, have high hopes for the HBHC. Bringing a wide and diverse group of players to the table, the coalition has increased the odds of finding common ground to implement and achieve the multilevel changes we need to positively affect beekeepers, pollinators and society in general."

The Agribusiness Scientist: Keri Carstens of DuPont Pioneer

"At DuPont Pioneer, we recognize the importance of both pest-control options and pollinators to the agricultural industry. These are not mutually exclusive. Pollinator health is a complex and interconnected issue; we value the collaborative and holistic approach the HBHC is taking. We chose to join because we feel this group is best positioned to make an impact through its focus on all aspects of this issue. The coalition will play a vital role in helping identify the best practices that will benefit everyone."

The Conservationist: Christi Heintz of Project Apis m.

"As the go-to organization at the intersection of honey bees and pollinated crops, PAm works to enhance the health and vitality of honey bees while improving crop production. The HBHC will allow PAm to accomplish even more than we can accomplish alone. The HBHC can and will go above and beyond what individual members can do on their own. The HBHC gives us access to partners it would take years to cultivate without it. In just six months, our working groups have already developed initiatives, collaborations and actions that will create measurable improvements in honey-bee health."

The Collaboration Consultant: Richard J. Crespin of CollaborateUp

"The coalition’s launch culminates months of work. We all came together last year with more than 100 other people who have the most at stake in honey-bee health. We came from across the food chain, representing every step from seed to mouth. We agreed on a single, if complicated, goal: restore bee health and protect the future of honey bees and the food supply, while benefiting other native and managed pollinators. Today, the HBHC is a very big tent working across the food chain to provide a North American clearinghouse for finding and scaling existing solutions and investing in new innovations. While we were launching during Pollinator Week, the White House issued a Presidential Memorandum and formed a federal task force to improve pollinator health, and we are actively engaging with these and other initiatives."

All of us

Leadership on this issue will take science-based research and innovation in four major areas: nutrition and forage, hive management, crop-pest management and cross-industry collaboration. Bees, like humans, need a robust and varied diet, so we are working to improve access to forage areas and to create new innovations in bee nutrition. The Varroa destructor mite has become one of the biggest challenges to healthy hive management to emerge in our lifetimes, and we will invest in transferring technology, educating beekeepers and new research to address this and other hive management challenges.

Feeding an ever-hungrier planet requires a variety of pest-control products and practices. While much already has been done to reduce and improve pesticide use and application, more can still be done to improve best management practices, to help ensure healthy bee and other pollinator populations. Last, we need better collaboration among all of us who have a major stake in the role of bees in production agriculture, and the HBHC will provide that structure.

The coalition is already a big tent, but we want it to grow even bigger. We will work with governments at all levels, conservation and environmental groups, and other industry players. And we want to work with you. Wherever you are in the food chain, we need your help. Please join the HBHC. Together we can make sure we promote more than hope, actually restoring the thriving population of honey bees that is so vital to a thriving food supply and a thriving agricultural economy.

Read at: GreenBiz.com

Stanford Researchers Discover Honey Bees Are Picky Pollinators

Stanford News   By Cynthia McKelvey   1/23/14

New research from Stanford demonstrates the impact of nectar-dwelling microbes on bees' dining preferences. Nectar inhabited by yeast did not deter bees from consuming the nectar, but bacteria-laden nectar caused bees to turn up their noses. The findings could lead to new insights on agriculture.

Huge swaths of the agricultural industry depend on the humble honeybee. According to the USDA, "about one mouthful in three in our diet directly or indirectly benefits from honey bee pollination." Biologists at Stanford are now looking into how the tiny ecosystems in the nectar of flowers affect the bees' dining preferences. Their work suggests bees may be picky pollinators, and their fussiness could confound complications from colony collapse disorder.

In a study published in the journal PLoS ONEtoday, a team of Stanford researchers found that bees were fine with a little yeast in their nectar, but bacteria rendered the nectar nearly undrinkable. Interestingly, the bacteria that made the nectar almost undrinkable are also found in the guts of honeybees. 

Ashley Good, a recent honors graduate in biology, led the study with Tadashi Fukami, a biology professor. They extracted three types of bacteria and yeast from the guts of honeybees found on the Stanford campus. After culturing the bacteria and yeast, the researchers put them into synthetic nectar. Then they placed the synthetic nectar, saturated with either bacteria or yeast, in fake flowers and watched what happened...

Read more...  http://news.stanford.edu/news/2014/january/bees-nectar-study-012314.html

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0086494

http://www.haccpeuropa.com/2014/01/26/understanding-bees-nectar-preferences-can-improve-pollination-efficiency/