Climate change linked to fewer bugs, study finds

Read the full story from NBC News.

The research builds on a body of work that has some scientists ringing alarms about the pace of the decline of insect populations.

Agriculture and Pollinating Insects, No Longer a Choice but a Need: EU Agriculture’s Dependence on Pollinators in the 2007–2019 Period

Bugin, G., Lenzi, L., Ranzani, G., Barisan, L., Porrini, C., Zanella, A., & Bolzonella, C. (2022). “Agriculture and Pollinating Insects, No Longer a Choice but a Need: EU Agriculture’s Dependence on Pollinators in the 2007–2019 Period.” Sustainability 14(6), 3644. https://doi.org/10.3390/su14063644

Abstract: One of the new objectives laid out by the European Union’s Common Agriculture Policy is increasing environmental sustainability. In this paper we compare the degree of average dependence index for each member state (ADIMS) in EU28 from 2007 to 2019 in order to verify the following: (1) whether there was a difference in this index when comparing two CAP periods—(a) from 2007 to 2013 and (b) from 2014 to 2019—and (2) which crops had a larger effect on the ADIMS. The study showed no significant variation in the average ADIMS at EU level between the first (2007–2013) and second (2014–2019) CAP periods. The AIDMS index highlighted three types of EU agriculture: (1) agriculture in Eastern Europe, including Bulgaria, Hungary, Romania and Slovakia, characterized by a high level of ADIMS (10.7–22) due to the widespread cultivation of oil crops as rapeseed and sunflower; (2) Mediterranean agriculture including Portugal, Spain, Italy, Croatia, Greece, Malta, Cyprus and France with lower AIDMS levels (5.3–10.3) given their heterogeneous crop portfolios with different degrees of dependence on animal pollination (almond, soy, rapeseed, sunflower and tomatoes) and (3) continental agriculture including Germany, Austria, Slovenia, Poland, the Czech Republic, Baltic countries, Benelux, Finland, Sweden and Ireland, which are characterized by the lowest ADIMS level (0.7–10.6) due to the widespread cultivation of cereals (anemophily and self-pollination) which increase the denominator of the index. The study suggests that a sustainable management of the agroecosystem will be possible in the future only if CAP considers pollinators’ requirements by quantifying the timing and spatial food availability from cultivated and uncultivated areas.

Planting mixes of flowers around farm fields helps keep bees healthy

Bees feeding in monoculture fields of single crops such as sunflowers crowd together and pass parasites to one another at high rates. Lauren Ponisio/University of Oregon, CC BY-ND

by Hamutahl Cohen, University of Florida

It’s springtime in California, and bees are emerging to feast on flowering fields – acres upon acres of cultivated almonds, oranges and other fruits and nuts that bloom all at once for just a few weeks. Farmers raise these lucrative crops in monoculture fields, each planted with neat, straight rows of a single type of crop.

The agricultural heart of California is the Central Valley, one of the most productive agricultural regions in the world. I recently drove north through the valley on Interstate 5, a 450-mile (724-kilometer) stretch of monoculture farms and agricultural land that runs from Bakersfield to Redding. Flowers were blooming as far as the eye could see. There is so much bloom here that commercial beekeepers truck in over 2 million colonies of bees in spring to ensure that every last flower is pollinated.

As a bee biologist, I study why bees are dying. Although monoculture blooms provide food for bees, scientists know almost nothing about how temporary mass-bloom events influence bee health.

I wondered whether bees in these monoculture fields were getting sick in the same way a crowd of hungry people with unwashed hands can get sick by converging at a brunch buffet. Imagine not washing your hands after picking up the tong for hash browns – hundreds of times in a row.

I found that bees foraging in monoculture pick up parasites at high rates. Disease is a leading cause of bee decline, so my research indicates that monoculture blooms are a threat to bees. However, I also found that farmers can reduce this threat by taking a page from backyard gardens and planting hedgerows with diverse mixes of flowers.

Adding flowering plants to their fields is an effective way for farmers to support bees.

Interacting bees can spread disease

Bees’ main goal in life is to collect pollen and nectar to feed their young. But as bees forage, they are exposed to bacteria, fungi and viruses, which can spread among bees via flowers.

For humans, social interaction or touching shared doorknobs in highly trafficked office buildings can spread viruses and other pathogens. Bee scientists joke that, for bees, flowers are the dirty office doorknobs.

Artificially providing animals with food can affect the spread of diseases in two ways: It can dilute them or amplify them. When a monoculture crop blooms in a landscape that’s otherwise void of food for bees, it offers an attractive pulse of pollen and nectar. When bees cluster together, disease may be more likely to spread between infected and noninfected bees.

But that’s not automatic. Flowers can feed bees and prop up their immune systems, making them less vulnerable to disease. Disease spread is also hampered if many different bee species are attracted to flowers, because not all bee species harbor all parasite species.

As the mix of bees in the community becomes more diverse, parasites are more likely to encounter unsuitable hosts, breaking up the the chain of transmission. This suggested to my research team that mass blooms could help bees under the right circumstances.

Large white boxes with bees on the outside, stacked near blooming almond trees.
Beehives next to an almond orchard in California’s Central Valley. MyLoupe/Universal Images Group via Getty Images

Diagnosing disease

In a study that colleagues and I published in late 2021, we examined whether monoculture blooms attracted bees, and whether this process resulted in more disease or less. We then examined whether adding diverse flowers to monoculture farms helped to promote healthy bees.

We studied bees in sunflower fields in California’s Central Valley. Sunflowers are grown for commercial oil manufacturing and rely heavily on pollinators such as honeybees, bumblebees, sunflower bees and sweat bees.

A hedgerow planted near monoculture sunflower fields provides bees with other flowers to pollinate. Lauren Ponisio/University of Oregon, CC BY-ND

Some of our sunflower study sites were grown as traditional monocultures, while others were grown adjacent to hedgerows, which are flowering strips of perennial plants such as California rose, Mexican elderberry and perennial sages. These hedgerows turn monoculture farms into more diverse systems.

Our team of professors, postdoctoral researchers and students walked through each site with aerial nets, cajoling bees into tiny sterile tubes. Back in the lab, we tested each bee for seven parasites commonly implicated in bee declines using molecular techniques.

Bees really like mass-bloom events. We discovered 35 different bee species visiting sunflowers, with their abundance highest at the peak of sunflower bloom. Places with historic legacies of growing sunflowers hosted more abundant bee populations than sites where sunflowers had been planted only recently. Even at farm sites with hedgerows, bees were consistently found foraging on sunflowers at higher numbers than on hedgerows.

But apparently, bee gluttony comes with a cost. We found that these increases in bee abundance were subsequently associated with higher rates of parasitism. Of the individuals we screened, almost half had at least one parasite, and about a third had multiple parasites. The more bees in sunflower fields, the more parasites. Sunflower blooms were aggregating bees, which in turn was amplifying disease risk.

Nearby hedgerows help bees

We also found something encouraging: When bees had access to hedgerows that contained many different kinds of flowers, they had lower rates of parasite infections. This suggests that in the presence of many flower types, bees disperse and spread across resources, reducing each individual bee’s likelihood of encountering an infected individual. Flower diversity may also provide immunity benefits to bees through other mechanisms, perhaps by enhancing nutrition.

Agencies, organizations and researchers are working to promote hedgerows and other forms of bee habitat. For example, the nonprofit Xerces Society offers farmers a certified “Bee Better” eco-label, which indicates to consumers that the farm has dedicated 5% of its land or more to pollinator habitat. And land-grant institutions such as the University of California, Cornell University and the University of Florida are teaching local communities about plant choices that work best for bees. As an agricultural extension agent, I believe that together, efforts like these can help bring back healthy pollinators by promoting habitat conservation.

Hamutahl Cohen, Extension Agent, University of Florida

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The secret to better coffee? The birds and the bees

Read the full story from the University of Vermont.

A groundbreaking new study finds that coffee beans are bigger and more plentiful when birds and bees team up to protect and pollinate coffee plants.  

Without these winged helpers, some traveling thousands of miles, coffee farmers would see a 25% drop in crop yields, a loss of roughly $1,066 per hectare of coffee.  

That’s important for the $26 billion coffee industry—including consumers, farmers, and corporations who depend on nature’s unpaid labor for their morning buzz—but the research has even broader implications.  

The forthcoming study in the Proceedings of the National Academy of Sciences is the first to show, using real-world experiments at 30 coffee farms, that the contributions of nature—in this case, bee pollination and pest control by birds—are larger combined than their individual contributions. 

The loss of insects is an apocalypse worth worrying about

Read the full interview at Vox. Oliver Milman is the author of a new book, The Insect Crisis.

A world without insects is a world we don’t want to live in, Milman told Vox. Yet we don’t seem to pay these critters much attention — even as many of them slip toward extinction. Science is increasingly showing that insects, on the whole, are declining quickly, he said. Some populations have fallen by more than 70 percent in just a few decades.

Averting an insect apocalypse starts with understanding why these famously uncharismatic critters matter — that’s one lesson he hopes his book can convey. Then there’s the question of how to help them. Fortunately, he writes, it’s pretty simple: We don’t need an action plan, we need an inaction plan. Insects love overgrown lawns, empty lots, and other untended spaces.

Interactions between bee gut microbiotas and pesticides

Read the full story from the University of Ottawa.

A major review has provided the first field-wide summary of how pesticide exposure affects social bee gut microbiotas and what pesticide-induced disturbances mean for bee hosts.

Study: Small gardens are just as crucial for bee conservation as big ones

Read the full story at Treehugger.

Whether it’s leaving hollow plant stems as nesting sites or making a watering hole for native bees, Treehugger is not short of tips and tricks for more pollinator-friendly gardening practices. Yet if you have only a small, urban garden to tend, it can sometimes be tempting to wish for a lot more space with which to help our furry, flying friends. It turns out, however, that size doesn’t matter all that much. 

At least, that’s the findings of a paper, titled “Turnover in floral composition explains species diversity and temporal stability in the nectar supply of urban residential gardens,” recently published in the Journal of Applied Ecology. Nicholas E. Tew of the University of Bristol and his team found—based on a survey of 59 urban gardens in Bristol, England—that while the amount of nectar produced by urban gardens varies widely, the variation has little to do with the size of a garden. Instead, factors like gardening practices and, interestingly, the relative wealth of a neighborhood were much more closely correlated.

Air pollution significantly reduces pollination by confusing butterflies and bees

Read the full story from the University of Reading.

A new study finds pollination reduced by almost a third when diesel fumes and ozone were present – the negative impact of these common air pollutants on pollination were observed in the natural environment.

Sunflowers’ invisible colors help them attract bees and adapt to drought

Read the full story from the University of British Columbia.

It turns out sunflowers are more than just a pretty face: the ultraviolet colours of their flowers not only attract pollinators, but also help the plant regulate water loss.

Solar parks could be used to boost bumblebee numbers, study suggests

Read the full story in The Guardian.

Lancaster University researchers say sowing wildflowers alongside panels would have benefits for farmers who rely on pollinators.