Science·What on Earth?

Urban beekeeping can be bad for wild bees

In this week's issue of our environment newsletter, we look at the downside of urban beekeeping and whether 2020 might end up being the hottest year on record.

Also: Could 2020 be the hottest year on record?

(Sködt McNalty/CBC)

Hello, Earthlings! This is our weekly newsletter on all things environmental, where we highlight trends and solutions that are moving us to a more sustainable world. (Sign up here to get it in your inbox every Thursday.)

This week:

  • Urban beekeeping can be bad for wild bees
  • Will 2020 end up being one of the hottest years on record?
  • 'Nature-based systems' may be best weapon in halting coastal erosion

Urban beekeeping can be bad for wild bees

(Emily Chung/CBC)

Urban beekeeping has been touted as a way to boost pollination and improve sustainability, food security and biodiversity in cities. Many people and businesses who've added beehives to their backyards and rooftops (including CBC) say they're doing it to help fight declines in bee populations.

But researchers say urban beekeepers are likely doing just the opposite when it comes to wild bee species.

The only bee species kept in beehives is the European honeybee, which is "a non-native species that's essentially livestock managed by people," said Charlotte De Keyzer, a Toronto bee researcher and founder of the site, which fights misinformation about bees. 

"So it's a bit like saying that you're going to save the birds of Canada by keeping chickens in your backyard."

Honeybees, which are kept in hives of 50,000 to 100,000, roam across the city and compete with native species for food — nectar and pollen from flowers. A recent study in Paris found fewer wild bees in areas with more beehives, and on average, studies have been finding managed honeybees have a negative impact on wild species.

Gail MacInnis is a postdoctoral researcher at Concordia University who is studying how beehives are affecting more than 170 wild bee species that live in Montreal, where about 2,000 honeybee hives have been added since 2013.

She noted that most wild bees are solitary and some are only active and able to collect food for two or three weeks of the year, so competition from a hive of 100,000 honeybees can be a huge problem.

She's trying to figure out how many beehives Montreal can sustainably support without harming wild bees, and how many flowers are needed to feed them. 

MacInnis and De Keyzer acknowledge that honeybees are important for agricultural pollination, and there are some benefits of urban beekeeping, too, such as honey production and providing an income for beekeepers.

But they think governments should restrict urban hives to protect wild bees, as Ontario has done.

So, if you want to boost wild pollinator populations and improve sustainability and biodiversity, what should you do? 

  • Do less work in your garden, De Keyzer says. "You can mow less, which increases the flowers in that area. You can apply less pesticides." Less mulching and tidying in your garden also increases the nesting areas available to wild bees, which often nest in the ground, dead wood or the hollow stems of some plants.

  • Plant flowers, MacInnis suggests.

  • Advocate for stronger urban bylaws and restrictions about where beehives can be kept, De Keyzer says.

MacInnis agrees that municipal governments can have a greater impact than individuals when it comes to protecting wild bees. Both researchers point to Toronto, which is covered by Ontario restrictions that make beekeeping illegal in much of the city, and has itself moved toward more bee-friendly landscaping with native plants and offers grants to community groups for pollinator flower gardens.

According to the City of Toronto, that's had other benefits, too — the native plants are more resistant to pests and don't require much maintenance, which lowers costs.

Emily Chung

Reader feedback

Nicole Mortillaro's story last week on 'binning' — that is, the practice of mining garbage and recycling bins for refundable or sellable plastic or glass — garnered a number of interesting responses.

One reader, Harry Cuerden, wrote: "I have been raccooning for over 20 years, picking up sellables and reselling and picking up scrap metal and selling to scrap yards. My friend came up with the word raccooning as raccoons pick through your garbage and take the good stuff."

John Doidge wrote, "I don't see much positive impact of binners taking from blue boxes…. These materials will be recycled. There would be no increase in recycling through this activity but there will be a loss of income to the municipalities who are running the blue box programs. This might result in them not adding new programs, such as compostables, to their city-offered waste reduction programs. If binners are collecting material that would otherwise not be recycled, that would be more positive."

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The Big Picture: The hottest years on record

One of the rites of summer is remarking on just how hot it is. Well, if you've been in Baghdad or Death Valley, Calif., recently, the answer would be searingly hot. The Iraqi capital recently registered 51.8 C; not to be outdone, Death Valley notched 53.3 C. While these are extreme cases, broader trends suggest the year 2020 could have a dubious distinction. Using a temperature baseline set around the end of the nineteenth century and readings from NASA and the National Oceanic and Atmospheric Administration in the U.S., it looks like this year could end up being the second-hottest on record, after 2016. As you can see from the chart below, the hottest years have all come in the last decade, and scientists acknowledge that it's largely the result of human-influenced climate change.


Hot and bothered: Provocative ideas from around the web

  • A number of new academic papers are leading to a similar broad conclusion: that the timing of a wide range of natural phenomena, from atmospheric pressure systems to ocean acidity, could be predicted a year, sometimes even a decade, in advance.

  • Apple recently revealed that it will be using "low-carbon" aluminum for the housing of some of its silvery laptops. The metal is chemically the same as the material used for things like pop cans and bicycle frames, but it's manufactured using a novel process that doesn't directly release greenhouse gases.

'Nature-based systems' may be best weapon in halting coastal erosion

(Steve Lawrence/CBC)

With sea levels rising faster in Nova Scotia than almost anywhere in the country, experts say the need for coastal property owners to take action to mitigate erosion is more important than ever.

As a result of a combination of land subsidence and climate change, it is projected that sea levels in Nova Scotia will rise between one and 2½ metres by 2100, while storm surges and wave action exacerbate coastal erosion.

Thousands of properties in Nova Scotia are on the coast.

"Climate change is here ... and reversing it doesn't look like it's actually going to happen in our lifetime, so if that's not a possibility, to fix it from the root end, then we have to take charge of the symptoms and then really engage people at education," said Rosmarie Lohnes, founder of Helping Nature Heal, an ecological restoration company based in Bridgewater, N.S.

Several initiatives are encouraging property owners to implement living shorelines — also known as nature-based systems — such as wetlands, tidal flats and revegetating the shoreline, rather than popular hard barriers, such as armour stones.

Lohnes said rock walls "are sort of an old technology and old methodology."

In fact, rock walls come with their own set of problems. Armour stone may protect the individual property but it causes the wave energy to be deflected to another part of the shoreline and blocks the natural movement of sediment, exacerbating erosion elsewhere. Waves can also erode around the stone, causing structures to collapse.

Lohnes said she encourages people to consider how planting the coast with a particular mix of native species can more effectively slow down erosion. "The right plants in the right place make all the difference, for sure."

Living shorelines are increasingly recognized as an important form of protection for coastal properties and communities. A 2018 report by the Insurance Bureau of Canada, for instance, recommended retaining and restoring "natural infrastructure," such as wetlands, as a way of reducing risks for those on the coast.

"Lots of people don't understand the ecosystem that they're living in," said Lohnes, who runs a program called Shore Up, which teaches people about living shorelines. "This is an opportunity to really talk to them about how the plants work, and how they work together, and then what happens when a storm arrives."

DG Blair, director of the Stewardship Centre for British Columbia, said the organization is in the process of bringing its Green Shores initiative to Nova Scotia. Green Shores is a credit and rating system, similar to LEED, the international green building certification system. It encourages property owners to adopt design standards that use natural systems to manage the shoreline.

The design standards provide best practices "guidance" on how to develop the shoreline in a way that conserves the environment and restores natural processes, Blair said. 

Data shows "that a well-designed nature-based solution can be as effective, if not more effective, for sea-level rise and increased storm surge, for example," said Blair. "If you can do a nature-based approach, usually it's less expensive and it proves to be more resilient."

Patricia Manuel, a professor in the school of planning at Dalhousie University in Halifax, said that while much of the education on nature-based systems has come from companies and not-for-profits, local governments can lead the way.

Manuel said living shoreline projects, such as ones that have been proposed or completed in Nova Scotia communities like Mahone Bay and Shelburne, provide an opportunity for governments to model better approaches to protecting the shoreline.

Instead of armouring the shore, municipalities can restore a wetland or use landscaping, "and then people can see how it works and take some assurance from that."

Nova Scotia is developing regulations for its Coastal Protection Act, which will protect new construction from flooding and rising sea levels by stipulating how close people can build to the coast.

Moira Donovan

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Editor: Andre Mayer | Logo design: Sködt McNalty

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