Un-BEE-lievable: The Buzz on Native Bee Conservation in Canada

Guest post by University of Toronto-Scarborough MEnvSc Candidate Rachel Siblock

Unless you’ve been living under a rock (much like native mining bees in Canada), you’ve probably seen the numerous campaigns to “Save the Bees”. Bee species across the globe are in decline. There are many factors that contribute to this decline, such as pesticide use, colony collapse, disease, habitat loss, and climate change¹. Many of these factors interact with one another, exacerbating the consequences and impacts. Conservation efforts are being implemented to try to stop the loss of these pollinators, and the valuable services they provide to humans. Canada is no exception. There are local, provincial, and national policies and programs operating and currently being developed in order to reduce the impacts of these threats. In the past few years, programs like The Bee Cause, Bees Matter, Feed the Bees, and others have implemented programs and recommendations in order to increase the bee populations in Canada. Honey Nut Cheerios has even campaigned to get the public engaged and involved in the conservation of bees. These programs, however, all have one common issue: they focus their efforts on Honey Bees. 

An example of a campaign by Honey Nut Cheerios, focusing on honey bees. 

There are no native honey bees in Canada. The most well-known bee in Canada was not even present in the country until it was introduced from Europe in the 1600s². The European Honey Bee was intentionally introduced to Canada for honey production, and since has increased in number dramatically, both in farmed and wild colonies. Honey bees have large colonies, allowing them to be easily managed and farmed. They also pollinate crops and produce honey, which may make them seem more economically valuable than their native, non-honey-producing counterparts. However, there have been unexpected impacts of the introduction of the European Honey Bee on native bee species in Canada.

            There are over 800 native bee species in Canada. While there are many different types of bees in Canada, the best understood group of native bees are bumble bees. Bumble bees have the ability to buzz pollinate, which allows them to obtain pollen from plants with pollen that is difficult to extract. Many of these plants are economically valuable, such as kiwi and blueberry crops. This, along with general pollination, makes managed populations of bumble bees worth several billion dollars annually³. Bumble bees naturally have low genetic diversity and can be subject to inbreeding depression, leading to declining populations and making the some species more vulnerable to extinction⁴. Threats can then interact with these low population levels, and intensify population loss. 

A male Rusty-patched Bumble Bee, one of Canada’s native bee species. It is currently listed as endangered in Canada.

Aside from facing the same threats as honey bees, native bumble bees are also threatened by the very presence of honey bees. Competition for resources with honey bees is a major threat to native bumble bees. A study performed in the United Kingdom found that bumble bees at sites with high honey bee density were significantly smaller in body size when compared to their relatives at sites with low honey bee density⁵. An additional study discovered a reduction of native bumble bee colony success when colonies were experimentally exposed to honey bees⁶. Honey bees generally produce larger colony sizes which can store a larger amount of resources than bumble bees. They also have the ability to communicate with one another about valuable floral resource locations⁷. Honey bees have a larger foraging range than native bumble bees, and have an increased ability to forage on introduced plant species⁷. These adaptations allow honey bees to outcompete native bumble bees, and commandeer sparse resources in the area.

            Threats from honey bees do not just end at competition; pathogens and parasites specifically adapted to honey bees have been shown to have the ability to spread to wild bumble bee populations. Managed honey bees are known to carry higher than natural levels of pathogens⁸, which can be transmitted to wild bumble bee populations when the bees interact. In particular, two pathogens endemic to honey bees, C. bombi and N. bombi, are wreaking havoc on bumble bee populations. While these pathogens do not have lethal effects, their sublethal effects can be devastating to colonies. These pathogens cause reduced pollen loads, a decline in flowers visited per minute, slower growth rates of colonies, decreased queen reproductive rates, shortened life spans and diminished colony growth⁸. With small populations already, entire bumble bee colonies can be wiped out by these pathogens. Honey bee parasites, such as the Small Hive Beetle, have also been shown to be able to spread to bumble bee colonies, where they consume the wax, pollen, and nectar stores of hives⁸. While honey bees have co-evolved with these parasites and pathogens for eons, bumble bees have not had the time to adapt to these threats, making them much more vulnerable to these hazards. 

Small Hive Beetle infestation in a honey bee colony. 

But why do we care about losing native bees? The same concerns about the loss of honey bees applies to native bees. Native bee species pollinate crops and flowers, which we depend on for food. It is estimated that about one in three bites of food we consume can be traced back directly to pollination by bees and other pollinators. However, native bees have been found to be more effective pollinators than honey bees. Some plant species in Canada rely solely on native bees for their pollination. With the loss of native bees, these plants will also become endangered, along with many other food crops requiring pollination. Additionally, there is a severe lack of research into native bees. Research tends to focus on honey bee populations, resulting in much more knowledge of honey bee behaviours, adaptations, actions, and responses to stressors. The truth is, we don’t know much about native bee species in Canada. We have no idea what the consequences of the loss of these species will be. However, this does not excuse us from protecting these bees. If anything, this lack of knowledge should increase our urge to protect them, so we have the opportunity to learn about them in the future.

            The native bee species in Canada share little life history traits with the European Honey Bee⁸, making many conservation efforts that focus on honey bees unsuccessful. Focusing conservation efforts on one species may not address the specific needs of native bees. In addition, by focusing on improving honey bee populations, there will be increased stress on native bees, which will lead to a decline in their populations. If we continue with these conservation strategies, we may threaten native species further.

            An increase in honey bee populations will increase parasite and pathogen levels in native bees, and also increase the competition between honey bees and native bees. So what can you do to focus conservation efforts on native Canadian bees? For starters, avoid the use of pesticides, which will decrease already low populations⁸. Improve your knowledge of bee species, and report invasive or introduced species in areas used by native bee species. Plant a wide variety of native plants with high pollen and nectar concentrations to ensure newly emerging bees have the resources they need to survive. And finally, avoid tilling, mowing, or burning in areas where native bee species, particularly ground dwelling species, are known to live. With increased knowledge of native bee needs, and species specific conservation efforts, it is hoped that native bee species will begin to rebound. Let’s BEE positive!

BEE Informed – To get involved with native bee conservation check out these links:

Native Pollinator Initiative – Wildlife Preservation Canada

Bumble Bee Recovery – Wildlife Preservation Canada

Help Native Bees – Conservation Halton 

Native Bee Information – Canadian Wildlife Federation

BEE-bliography:

    1.     Pettis, J.S., and K.S. Delaplane. 2010. Coordinated responses to honey bee decline in the USA. Adipologie 41:256-263.

    2.     van Engelsdorp, D., and M.D. Meixner. 2010. A historical review of managed honey bee populations in Europe and the United Sates and the factors that may affect them. Journal of Invertebrate Pathology 103:80-95.    

    3.     James, R., and T.L. Pitts-Singer. 2008. Bee Pollination in Agricultural Ecosystems. Oxford University Press, USA.

    4.     Zayed, A., and L. Packer. 2005. Complementary sex determination substantially increases extinction proneness of haplodiploid populations. Proceedings of the National Academy of Sciences of the United States of America 102:10742-10746.

    5.     Goulson, D., and K. Sparrow. 2009. Evidence for competition between honey bees and bumble bees: Effects on bumble bee worker size. Journal of Insect Conservation 13:177-181.

    6.     Thomson, D. 2004. Competitive interactions between the invasive European honey bee and native bumble bees. Ecology 85:458-470.

    7.     Goulson, D. 2003. Effects of introduced bees on native ecosystems. Annual Review of Ecology, Evolution, and Systematics 34:1-26.

    8.     Colla, S.R. 2016. Status, threats and conservation recommendations for wild bumble bees (Bombus spp.) in Ontario, Canada: a review for policymakers and practitioners. Natural Areas Journal 36:412-426.

Image Sources:

  1. https://bringbackthebees.ca

  2. https://inaturalist.com

  3. http://beeaware.org.au/archive-pest/small-hive-beetle/#ad-image-0

Floral diversity increases bee abundance and diversity

*This is a guest post by Aswini Kuruparan- student in my 'Causes and Consequences of Biodiversity' course.

Bees are amongst the most crucial pollinators in the world and are critical for the success of our food crops. In fact, bees and other pollinators are responsible for the pollination of 87% of all flowering plant species (Lerman, 2018). However, due to the changes that humans have imposed on the environment through land use and agricultural practices, we see declines in both the numbers and diversity of bees (Nicholson, 2017). Recent evidence has been compiled to show that the composition of agricultural fields, tillage and lawn mowing frequency can significantly affect bee population size and diversity by directly affecting floral diversity. 

Agricultural fields can see more bee abundances and diversity with more floral diversity

The role of bees in the pollination of our food crops is essential to the success of global food production and feeding people around the world (Photo M. Cadotte).

Studies have shown that increasing floral diversity in agriculture can increase the size and diversity of bee populations attracted to those fields. In fact, one experiment looked at the correlation between floral diversity and population growth in stingless social bees (Kaluza, 2018). Their results indicate a positive correlation between floral diversity and bee population growth. They attribute this positive correlation with the continuous food supply available in florally diverse environments. In monocultures, all plants bloom around the same time period thus providing a narrow time interval in which bees would have sufficient food for population growth. A more diverse agricultural system would be accompanied by a larger range of blooming periods thus providing the food needed for bee populations to grow. Another experiment conducted in the vineyards of Austria came to a similar conclusion. This experiment also found that forage availability is the most significant factor to affect species richness in wild bees (Kratschmer, 2018). These findings indicate that we can promote bee diversity through diversifying the variety of floral plants in and around agricultural fields.

Another factor that indirectly affects bee population sizes and diversity is human activity in the form of soil tillage. In the study above conducted on the Austrian vineyards, the experimenters also compared the effects of no-tillage to alternating tillage and found that alternating tillage displayed slightly increased wild bee abundance and diversity relative to a no-tillage environment (Kratschmer, 2018). In this experiment no tillage was defined as a vineyard that had not undergone tillage in 5 or more years and alternating tillage was defined as a vineyard where every other row was tilled 1-3 times a year. The reasoning behind why more diversity and numbers of bees were found in alternating tillage sites was because those sites displayed higher forage availability and increased flowering plant species richness in comparison to untilled soils. Although the study found that directly increasing floral diversity had a higher impact on bee diversity, it should not be overlooked that soil tillage can also increase bee diversity and that these findings can open future research into the impacts that other steps in agriculture have on bee diversity.

Outside of agricultural practices, how often homeowners mow their lawns also affects bee biodiversity and numbers by affecting floral diversity. A study put this to the test by mowing lawns either once, twice or three times a week (Lerman, 2018). Their study revealed that mowing lawns less frequently led to increased bee biodiversity and abundance. They observed that lawns that were mowed every 3 weeks had 2.5 times more flowers than the ones mowed every 1 or 2 weeks thus providing more vital resources to bees. They suggest that homeowners minimize the frequency at which they mow their lawns to benefit bee conservation efforts by allowing for the growth of more flowers on their lawn. This shows that everyday people outside the agricultural industry can also help conserve bee diversity.

Homeowners can help increase bee biodiversity by decreasing their lawn mowing habits

Recently, Walmart has filed for a patent on autonomous robotic bees as a solution to the dwindling bee population, but this approach is not as feasible as preserving current bee diversity and making changes to promote their population growth (Potts, 2018). The economic cost of manufacturing and running these robotic bees to sustain our global food crops would be hundreds of billions of dollars. Comparatively, the pollination services by bees and other insects that are free of cost have a monetary value of over 200 million Canadian dollars (Kratschmer, 2018). It is more financially feasible to fund efforts to promote bee diversity through diversifying our agricultural systems than to build and operate these robotic bees. Moreover, robotic bees would also not be able to sufficiently capture the diverse traits possessed by various bee species to efficiently pollinate specific types of flowers. The time and resources needed to fine-tune traits which have already been perfected over years of natural selection in real bees into robots would be put to better use towards conserving and growing our bee populations.

Although it is important to acknowledge that our actions are partly to blame for the decline in bee diversity over the years, it is also important to realize that we can make changes to enhance bee diversity from here on. These studies have shown that bee diversity can be improved by increasing floral diversity through diversifying the vegetation in and around our crops, coupled with homeowners reducing the number of times they mow their lawns and further investigating how various steps in agriculture like tillage can affect bee diversity. With this in mind, it is critical that future funding is put towards conserving bee diversity rather than towards replacing them with robotic bees.

References

Kaluza, B. F. (2018). Social bees are fitter in more biodiverse environments. Scientific Reports, 8. doi:https://doi.org/10.1038/s41598-018-30126-0

Kratschmer, S. (2018). Tillage intensity or landscape features: What matters most for wild bee diversity in vineyards? Agriculture, Ecosystems & Environment, 266, 142. doi:10.1016/j.agee.2018.07.018

Lerman, S. B. (2018). To mow or to mow less: Lawn mowing frequency affects bee abundance and diversity in suburban yards. Biological Conservation, 221, 160. doi:10.1016/j.biocon.2018.01.025

Nicholson, C. C. (2017). Farm and landscape factors interact to affect the supply of pollination services. Agriculture, Ecosystems & Environment, 250, 113. doi:10.1016/j.agee.2017.08.030

Potts, S. G. (2018). Robotic bees for crop pollination: Why drones cannot replace biodiversity. Science of the Total Environment, 642, 665-667. doi:10.1016/j.scitotenv.2018.06.114

Tea Time with Amazigh People

Guest post by University of Toronto-Scarborough MEnvSc Candidate Erin Jankovich

 “How do they survive?” This is the question I kept asking myself over and over as I sat sipping my mint tea on the clay floor of an Amazigh cave in the Moroccan mountains. Their faces, hands, tea-kettle and even my cup were layered with dirt and soot. Outside, prevailing winds dusted the lonely peaks of the High Atlas with orange silt. I never expected to stumble across an indigenous settlement when I set out on my hike that day, let alone be invited for tea. This was by no means a fancy tea party, but it certainly was a memorable one.

Women plucked leaves from dry aromatic plants and a man filled a kettle for more tea. A toddler sat beside me and gestured to trade his clay ball for my Nikon. I felt like a fly on the wall in a National Geographic documentary.

I was on to my third cup of tea when a young man broke the silence. “Hello, do you speak English”, I heard from behind me. Dressed in traditional Amazigh clothes, this young man carrying a notepad and pen excitedly sat down beside me. He was a university student from Japan who had been living with this Amazigh family for four months to learn about their culture. Perfect! Maybe he could enlighten me as to how these people sustain their lives on this rugged mountain top - surely there was more to it than mint tea.

Mint tea, a traditional Moroccan drink and symbol of hospitality. Photography: Erin Jankovich

The young man pointed out across the valley and said “see”. For a while, all I saw was an expanse of orange rock but eventually like a stereogram the landscape came to life. Those little black dots were goats, dozens of goats! He walked me to the trailhead and pointed at the pale green tufts across the landscape. Mint, rosemary, sage, thyme, and verbena – these aromatic plants were right beneath my nose. This dusty landscape wasn’t so dead after all. He explained that the Amazigh people have extensive knowledge of the medicinal properties of hundreds of plants that grow in the High Atlas, and women will take several hour journeys to sell herbs in the valley markets. I wanted to learn more, but I was reminded of the long trek back to Tinerhir. I said goodbye, and thanked them all for such generous hospitality.

Afternoon tea with Amazigh family. Photography: Erin Jankovich

Morocco is dominated by a mountainous interior, bordered with rich coastal plains to the west and Sahara desert to the east. Since coming home from my trip, I have learned that this unique geography falls within the Mediterranean basin, a global biodiversity hotspot teeming with endemic flora and fauna found nowhere else on the planet (Rankou et al. 2013). Morocco alone has 879 endemic plants, the majority of which are restricted to the High Atlas region (Rankou et al., 2013).

The rich biodiversity of the High Atlas has been known to the Amazigh people for thousands of years, but only recently have researchers and scientists begun to draw their attention to this unique area. In 2015, scientists used IUCN Red List criteria to assess the status of endemic Moroccan flora and determined that many species are at risk of extinction due to climate change and habitat degradation (Rankou et al., 2015). These scientists emphasized that mountainous regions such as the High Atlas are especially sensitive to changes in climate and should be a top priority for conservationists, but so far very little research has gone into understanding the vegetation dynamics of this region.

Fresh and dry plants used for medicinal purposes found in traditional markets (image from Bouiamrine, 2017).

Many plant species picked by the Amazigh are highly toxic and dangerous to humans if not used appropriately (Mouhajir et al., 2001). Anecdotal evidence through surveys and interviews have revealed that the Amazigh people, specifically senior women, are experts in distinguishing between medicinal herbs and continue to pass on this traditional knowledge from one generation to the next (Bouiamrine, 2017). Many Moroccans still rely on traditional medicine to maintain good health thus conservation of these endemic herbs is critical for both the lives of the Amazigh and Moroccan market economy (Bouiamrine, 2017).

An Amazigh woman journeys across rugged terrain to sell herbs in modern markets. Photography: Erin Jankovich

I know better now that not all hotspots of biodiversity look like lush tropical jungles, but what they do have in common is an abundance of unique species that are threatened with extinction. Internationally the Mediterranean Basin has been recognized as providing significant ecosystem function and I was pleased to find that the Moroccan government has set national targets to preserve biodiversity and inventory traditional knowledge by 2020 (CBD, 2011).

Who better than the indigenous people of the High Atlas to help us understand the historical distribution of endemic plants and potential range shifts induced by climate change? Through sensitive and purposeful strategies for interaction with the Amazigh people—like the young student sharing a tea in the mountain—we may find that complimenting science with traditional ecological knowledge is the key to saving these unique landscapes.

References
Bouiamrine, E.H., Bachiri, L., Ibijbijen, J., & Nassiri, L. (2017). Use of medicinal plants in Middle Atlas of Morocco: potential health risks and indigenous knowledge in a Berber community. Journal of Medicinal Plant Studies, 5(2), 388-342.
Convention on Biological Diversity (2011). Electronic source. Retrieved from: https://www.cbd.int/countries/targets/?country=ma
Mouhajir, F., Hudson, J.B., Rejdali, M., & Towers, G.H.N. (2001). Multiple antiviral of endemic medicinal plants used by Berber peoples of Morocco. Pharmaceutical Biology, 39(5), 364-374.
Rankou, H., Culham, A., Jury, S.L., & Christenhusz M.J.M. (2013). The endemic flora of Morocco. Phytotaxa, 78 (1), 1-69.
Rankou, H., Culham, A. ,Taleb, M.S., Ouhammou, A., Martin, G., & Jury, S.L. (2015). Conservation assessments and Red Listing of the endemic Moroccan flora (monocotyledons). Botanical Journal of the Linnean Society, 177, 507-575.

Florida’s coastal nightmare

*This is a guest post by Katherine Datuin- student in my 'Causes & Consequences of Biodiversity' course. 

Imagine going on vacation to beautiful, warm Florida just to find entire beaches strewn with the rotting remains of hundreds of fish, sea turtles and manatees. This is unfortunately not a nightmare, but a current reality for the residents of southwestern Florida, and it has been this way for almost a year now. What causing all this? This little guy. 

Figure 1. Kareina brevis living cell. Photo modified from Florida Fish & Wildlife Conservation Commission.

These events were brought to my attention through a recent article published by Vox news highlighting the consequences of such large and long-lasting harmful algal blooms, specifically the “Red Tide” in southwestern Florida (Resnick B. 2018). Kareina brevis, the algal species responsible, has been in bloom since November of last year. According to the article, this event constitutes the longest “Red Tide” algal bloom in history. Regularly, blooms occur seasonally, lasting only from a few weeks to a couple months. The length of bloom in combination with the species responsible is catastrophic for the surrounding environment. This species of algae produces a suite of neurotoxins known as brevetoxins (Gebhard et al. 2015). Exposure to these toxins within marine environments has resulted in massive fish kills and increased mortality in loggerhead turtle, and marine mammal populations (Walsh C. et al. 2010).

 

Figure 2. Kemp's ridley sea turtle on Sanibel Island. Photo modified from Andrew West/The News-Press via USA TODAY

Then why is all this so scary? It is because such Red Tide of this nature have never been recorded. This situation is novel, and therefore its overall effect on the underlying ecosystem is unknown. What is known is that mortality rates are increasing. More and more animals are dying as a result of this bloom, but the significance of the losses is still unknown. Will the affected species recover following this event? Will species be lost? Is the length of this bloom unique or will future blooms also be so long? What factors contributed to or enabled such a long-lasting bloom?   

It is equally important to consider the impacts such events will have on us humans. Human health can be directly or indirectly effected by these toxins through toxic aerosols and consumption of contaminated shellfish respectively. Studies have shown that an increased incidence of both respiratory and digestive illnesses can be found in relation to Red Tide presence, especially in those aged 55 or older (Hoagland P. et al. 2014). According to the United States Census Bureau, from estimates in 2017, about 20% of Florida’s population is 65 years of age or older. This means a high percentage of the population is at risk of suffering either respiratory or digestive illnesses due to this bloom. As well as its effects on human health, the Red Tide greatly impacts Florida’s fishing and tourism industries.

Figure 3. Red Tide devastation in Florida. Photo modified from Ben Depp Via National Geographic.

What can we do to prevent these blooms?
Although the specific conditions which enabled this bloom are unknown, many studies have hypothesized which factors likely contributed to this increase in length and frequency. The article states that human activity and climate change are likely the two factors with greatest influence. This is probably because like all other algal species, K. brevis requires sufficient macro-nutrient to enable blooms (Hoagland P. et al. 2014). Increased agricultural practices, water runoff and changes to atmospheric depositions could all contribute to a surplus of nutrients entering the water system and thus becoming available for these algae (Hoagland P. et al. 2014).  To mitigate the impacts of Red Tides, it is important to educate the local communities about how their actions effect their environment. For example, improving the public understanding of how fertilizer use can lead to greater blooms and how blooms effect charismatic species like turtles and dolphins. The public should also be informed of the ways in which Red Tides directly affect their communities from damage to fisheries and tourism to public health concerns.

The effects of the Florida Red Tide can be felt among all trophic levels in the surrounding marine and terrestrial environments. The causes and consequences of this specific event are still unknown and will likely be the subject of rigorous future studies. We should look to determine how we can prevent or minimize the length and severity of these blooms in order to protect the marine environment, the fisheries and tourism industries, and finally our own health.


References
Gebhard, E., Levin M., Bogomolni A., Guise S.D., “Immunomodulatory effects of brevetoxin (PbTx-3) upon in vitro exposure in bottlenose dolphins (Tursiops truncates)” Harmful Algae. 44(2015): 52-62.

Hoagland P., Jin D., Beet A., Kirkpatrick B., Reich A., Ullmann S., Fleming L.E., Kirkpatrick G. “The human health effects of Florida Red Tide (FRT) blooms: expanded analysis”. Environment International. 68 (2014) 144-153.

Resnick, B. Why Florida’s red tide is killing fish, manatees, and turtles. Vox news. October 8th, 2018. https://www.vox.com/energy-and-environment/2018/8/30/17795892/red-tide-2018-florida-gulf-sarasota-sanibel-okeechobee

Walsh C.J., Leggett S.R., Carter B.J., Colle C. “Effects of brevetoxin exposure on the immune system of loggerhead sea turtles”. Aquatic toxicology. 97(2010): 293-303.