Native pollinators and their role in pollination
Wild pollinators deliver a significant but unknown share of pollination services to agriculture [1, 2, 3]. A recent article published in Science points out that flower visitation by wild insects showed a universally positive impact on all 41 fruit crop systems that were examined worldwide [7]. In contrast, only six of these fruit crops responded positively to flower visitation by honey bees [7]. For horticulture crops such as watermelons and tomatoes, studies indicate that honey bees are less effective than native bees [4]. Farmers perceive the same for blueberries [9]. Thus, while honeybees are important, it is clear that native pollinator species are critical for plant productivity. In Ontario, almost all ecological farms and many larger organic vegetable farms almost exclusively rely on native pollinators to provide pollination services for their crops (e.g. Pfennings, Zephyr Organics) [8]. With much uncertainty remaining, it is apparent that native biodiversity increases the resiliency of our food system; rich pollinator biodiversity helps compensate for environmental stresses and also landscape degradation across scales. Diverse native pollinators thus increase the resilience of pollination services for agriculture and nature [6].
Decline of honeybees and wild pollinators
There is clear evidence of recent declines in both wild and domesticated pollinators, and parallel declines in the plants that rely upon them [10, 11, 12].
Neonicotinoid pesticides are most widely cited as causes for this decline. The direct toxicity of concentrated dusts and spray from such pesticides has long been acknowledged, and farmers aim to minimize the exposure with their application practices. Recently, evidence is growing that there are sub-lethal dosage impacts on the long-term survival of honeybees. For example, Chensheng and his colleagues from Harvard University [13] recently showed how very low dosages of neonicotinoid pesticides hardly impact the survival of honeybees during summer, but cause high death rates during winter. Other research indicates that native pollinators are even more susceptible to neonicotinoids. For example, while colony-building honey bees may be able to deal with a loss of 20% of worker bees without impacting the colony’s survival, differences in the foraging strategies and colony sizes of native species, such as those of solitary bees or bumble bees, could result in similar mortality rates having a much greater impact on a species' persistence in an area. Modern pesticides are systemic and remain active in the plant for several months, including the pollen [14]. We are only beginning to understand the impacts that chronic exposure to sub-lethal doses of these neuro-toxins have on our insect pollinators.
Ontario`s honey bee industry is being hit hard by mass dying of honey bees. The Ontario Beekeepers’ Association names neonicotinoid pesticides as a significant contributing factor. The Ontario Ministry of Agriculture and Food (OMAF) formed a working group that includes equipment manufacturers, seed companies, grain farmers, the University of Guelph, Bayer Crop Science, CropLife Canada, Syngenta, several government agencies, and beekeeper representatives in an attempt to arrive at a consensus on actions to take regarding neonicotinoids. This stakeholder group could only come to a consensus on a few immediate actions, but large gaps in opinion remain between beekeepers, chemical input suppliers, and farmers on the action to be taken [15]: “The thirteen options for action include improvements to growing practices and communications, environmental enhancements, technology advancements and training as well as regulatory approaches. Where consensus was reached, government and industry have collaborated extensively and taken action to implement those options.” (Executive Summary). OMAF is performing additional research to map risks for crop exposure to pests and economic costs of abstaining from the use of neonicotinoids [16]. This research may lead to actions in line with the minimum-action demand of the Xerces Society for Invertebrate Conservation [14], who recommends returning to integrated pest management practices where pesticides are only applied if high pest pressure is present, instead of generally coating all seeds pre-emptively across our landscapes [17]. In 2013, Europe decided to implement a two-year total moratorium on the most common neonicotinoid pesticides, but it remains open which other alternatives European farmers will find to curtail damage from pests.
Pesticides are not the only causes of pollinator decline. Habitat destruction, for example the removal of hedge rows and the loss of native plants and plant diversity, are additional drivers for their decline. Introduced pests such as the varroa mite (Varroa destructor) and the diseases they vector are spreading and causing major problems for honey bees. Adverse effects from pesticides are thus only one aspect of concern that reflects the realities of our complex food system.
The situation in Grey Bruce
Grey and Bruce Counties are the home to many beekeepers and harbour many large natural areas, pastures, hedge rows, wetlands, and forests within their boundaries. The most recent data from Statistics Canada from 2011 indicate that a beekeeper in Ontario owns an average of 32 hives [18], whereas our area is home to a number of larger commercial beekeeping operations, whose hives number in the hundreds. The overall good performance of beekeepers in the watersheds of Bighead River, Grey Highlands, and the Bruce Peninsula can partly be attributed to their remoteness, but also to the skill, care, and caution that characterizes our local bee keepers.
Little is known about the state of native pollinators in this area, but it is likely that there is a steep gradient depending on the diversity of landscape and the existence of foraging and nesting habitat. Also, with the conversion of pasture-based landscapes into grain and oil seed crops, changes in honey bee, native pollinator, and other animal populations can be expected. However, at this point no one is even looking at these changes.
[1] Potts, Simon G., et al. "Global pollinator declines: trends, impacts and drivers." Trends in ecology & evolution 25.6 (2010): 345-353.
[2] Winfree, Rachael, Ramiro Aguilar, Diego P. Vázquez, Gretchen LeBuhn, and Marcelo A. Aizen. "A meta-analysis of bees' responses to anthropogenic disturbance." Ecology 90, no. 8 (2009): 2068-2076.
[3] Cane, James H., and Vincent J. Tepedino. "Causes and extent of declines among native North American invertebrate pollinators: detection, evidence, and consequences." Conservation Ecology 5.1 (2001): 1.
[4] Ricketts, Taylor H., James Regetz, Ingolf Steffan‐Dewenter, Saul A. Cunningham, Claire Kremen, Anne Bogdanski, Barbara Gemmill‐Herren et al. "Landscape effects on crop pollination services: are there general patterns?." Ecology letters 11, no. 5 (2008): 499-515.
[5] Mayer C, Adler L, Armbruster WS, Dafni A, Eardley C, Huang S-Q, Kevan PG, Ollerton J, Packer L, Ssymank A, Stout JC, Potts SG, Pollination ecology in the 21st century: Key Questions for future research, Journal of Pollination Ecology, 3, 2011, 8 – 23.
[6] Winfree, Rachael, and Claire Kremen. "Are ecosystem services stabilized by differences among species? A test using crop pollination." Proceedings of the Royal Society B: Biological Sciences 276, no. 1655 (2009): 229-237.
[7] Garibaldi, Lucas A., Ingolf Steffan-Dewenter, Rachael Winfree, Marcelo A. Aizen, Riccardo Bommarco, Saul A. Cunningham, Claire Kremen et al. "Wild pollinators enhance fruit set of crops regardless of honey bee abundance." Science 339, no. 6127 (2013): 1608-1611.
[8] Personal communication with Jenn Pfenning (Pfenning’s Farm) and Douglas Eng (Zephyr Organics) .
[9] Rader, Romina, James Reilly, Ignasi Bartomeus, and Rachael Winfree. "Native bees buffer the negative impact of climate warming on honey bee pollination of watermelon crops." Global change biology (2013).
[10] Potts, Simon G., et al. "Global pollinator declines: trends, impacts and drivers." Trends in ecology & evolution 25.6 (2010): 345-353.
[11] Jeroen P van der Sluijs, Noa Simon-Delso, Dave Goulson, Laura Maxim, Jean-Marc Bonmatin, Luc P Belzunces, Neonicotinoids, bee disorders and the sustainability of pollinator services, Current Opinion in Environmental Sustainability, Volume 5, Issues 3–4, September 2013, Pages 293-305, ISSN 1877-3435, http://dx.doi.org/10.1016/j.cosust.2013.05.007.
[12] Evaluation of Canadian bee mortalities in 2013 related to neonicotinoid pesticides. Health Canada Interim Report. Available online: http://www.hc-sc.gc.ca/cps-spc/pubs/pest/_fact-fiche/bee_mortality-mortalite_abeille-eng.php .
[13] Chensheng, L. U., Kenneth M. WARCHOL, and Richard A. CALLAHAN. "Sub-lethal exposure to neonicotinoids impaired honey bees winterization before proceeding to colony collapse disorder." Bulletin of Insectology 67, no. 1 (2014): 125-130.
[14] Hopwood, J., M. Vaughan, M. Shepherd, D. Biddinger, E. Mader, S. H. Black, and C. Mazzacano. "Are Neonicotinoids Killing Bees? A Review of Research into the Effects of Neonicotinoid Insecticides on Bees, with Recommendations for Action. 40pp. Portland, OR: The Xerces Society for Invertebrate Conservation." The Xerces Society for Invertebrate Conservation, Portland, OR (2012).
[15] Ontario Bee Health Working Group Report. Ontario Ministry of Agriculture and Food (OMAF) and Pest Management Regulatory Agency (Health Canada) (PMRA). March 19, 2014. Retrieved online on May 21, 2014 at: http://www.omafra.gov.on.ca/english/about/beehealthworkinggroupreport.htm .
[16] Special On-Farm Corn Trials – Farm Cooperators Wanted! Project leader: Jocelyn Smith, University of Guelph. Ontario Soil and Crops Association (OSCIA), February 27, 2014. Retrieved from www.ontariosoilcrop.org/docs/oscia_news_neonic_trials_feb27_2014.pdf on May 21, 2014.
[17] Recommendation from Mace Vaughan, Director of the Xerces Society, at the Ontario Fruit & Vegetable Convention, Niagara Falls, Ontario, January 2014.
[18] Production and Value of Honey and Maple Products (23-221-X). Statistics Canada. Retrieved online at: http://www5.statcan.gc.ca/olc-cel/olc.action?objId=23-221-X&objType=2&lang=en&limit=0 .
Project goal
This project proposes to win citizens who already have experience in nature observation to become stewards for native pollinators. We seek to identify and develop a strategy that successfully monitors the state of our native pollinator populations as a citizen science project, not unlike the annual Christmas bird counts that birders engage in, or the amphibian and reptile counts of road kill.
Our target group includes ecological farmers and community groups. Ecologically-minded farmers not only spend considerable time already conducting field observations of their plants, but also have a strong interest in maintaining and improving pollinator health. From a scientific monitoring perspective, these farmers remain at the same location for a long time, which promises continuity and good return on investment for their education about pollinators. At the same time, community groups such as schools, conservation groups, community gardens, and garden clubs have large networks and may have more time at hand for observation and monitoring tasks, and even for the development of a robust but easy monitoring method that is the objective of this pilot project. Ultimately, we see education for ecologically interested farmers and community groups as strategy to win a strong partner and advocate for native pollinators.
For the 2015 season, Ontario Nature has expressed great interested in supporting a farmer-led initiative on pollinator observation with their expertise in citizen science, data analysis, and funding. To build a meaningful partnership between farmers and conservationists, the 2014 pilot season aims to build capacity and experience within the farming community in what works for them, as well as collecting initial data to help refine the project in its next stages.
Pilot project actions
With the interest and financial support of ten ecological farmers, this project was initiated and a set of pollinator monitoring options were gathered from other citizen science projects. For 2014, the main goals are capacity building, habitat assessment, and testing of selected monitoring approaches by collaborating with two groups, in order to develop a protocol to observe and monitor the state of our native pollinators:
(1) Ecological farmers with a focus around Southwestern Ontario, and
(2) Community groups (garden clubs, schools)
The first activity was a workshop on April 14th, 2014, where ideas were discussed with leaders of the ecological farming community, and the project received further direction. This strain of action will continue within the internship program of the CRAFT network, as well as with the Ecological Farmers of Ontario, with whom we submitted a grant proposal.
We hope to find resources that will help our expert travel to all participating farms and perform habitat assessments, as well as data analysis of all monitoring data that we generate with our participants.
In Grey Bruce, we recently received grant funding from the TD Friends of the Environment to help embark on the 2014 pilot project. Proposed activities are to replicate the monitoring activities that are being conducted by ecological farmers, but working specifically in Grey Bruce with community, youth groups, and the interested public. The purpose of this work is to raise awareness of native pollinators and the threats they face, and also to test the monitoring strategies that are being developed with the ecological farmers.
Partners
The project is executed in collaboration with the Ecological Farmers of Ontario
Visit EFAO, the Collaborative Regional Alliance for Farmer Training in Ontario
Visit CRAFT, and the Grey Sauble Conservation Authority
Visit GSCA.
Acknowledgement
Seed funding was provided by 10 farmers
See Participating Farmers. Without their encouragement and financial donations, this project would not have happened. Also, we are grateful for funding provided by the TD Friends of the Environment Foundation, who enable us to purchase many of the workshop materials, plants, and print materials. Thank you!
Contact
Jeri Parrent
Email pollinators@gbcae.com
Thorsten Arnold
Tel. 519 935 3005
Email Thorsten.arnold@gbcae.com
This page lists options for observing and monitoring native pollinators. The methods vary in objective and level of involvement. We differentiate three main objectives:
(1) Measuring pollination success.
(2) Observation and counting of pollinator diversity and abundance.
(3) Colonization of nesting habitat.
Please find examples for each of these below!
This section focuses on determining pollination success by measuring the percentage of flowers that are successfully pollinated relative to the total number available. The approach focuses on the outcome (pollination) rather than the details involved in the process, such as the identity and diversity of the pollinator community responsible for pollination. It is somewhat similar to monitoring birds by measuring how long it takes until a bird feeder is empty. It gives neither information about the diversity, nor the types of pollinators, but indicates areas where plant productivity has become limited due to a lack of pollination success.
(1a) The purple stemmed aster
The purple-stemmed or swamp aster (
Symphyotrichum puniceum) flowers in its second year in late summer and produces seed heads containing about a hundred seeds each. In comparative experiments, it was determined that: (a) it is relatively easy to distinguish pollinated from unpollinated seeds, and (b) partial pollination of this species indicates lack of pollinators. Pollination is quantified during the seed stage, so this experiment will take time before results can be evaluated.
(1b) Clover flowering duration
Red clover (
Trifolium pratense) and white clover (
T. repens) are common and easily established cover crops where pollination success can be observed even during the flowering stage. Each clover flower consists of multiple florets that are pollinated independently. With little practice, it is easy to distinguish: (a) florets that have not yet opened, (b) open florets, and (c) finished florets that turn brown immediately after pollination. This experiment covers a number of flowers with cages to prevent pollination, then removes the cage for a determined length of time and replaces the cage. Participants then count the percentage of florets that are pollinated, which are identified by their brown colouration. Results are available after few days.
(1c) Field transects and pollination intensity
In a large field, pollination can diminish from the edges toward the center if there are not sufficient pollinators. Pollination is crucial for successful plant productivity. As a result, complete pollination across fields is of great interest to farmers. One useful way to compare pollinator density and determine pollination success for a crop of interest is to observe pollinators as you move from field to adjacent natural areas. Using a transect method, participants may perform stationary pollinator monitoring at a series of locations of uniform distance from one another, moving from natural area to crop.
Specific observation and counting strategies generate data that can be compared across habitats, geographic regions, and correlated with other factors such as land use type and insecticide use. Observations can be taken at different levels of comfort of the observer. This ranges from major classification (bee, wasp, fly, beetle, butterfly, moth) to more specific identification (species or pollinator “type”- e.g., sphinx moth, sweat bee, etc). Observation is also a good starting point to understand and recognize the diversity of pollinator insects, and – to those who embrace it – provides a moment of peace after a busy day.
(2a) The Great Sunflower Project
During the flowering time of a sunflower (Lemon Queen), participants conduct a 15-minute observation period on a weekly basis to identify and record the pollinators visiting the sunflowers. This strategy replicates a successful citizen science project that was first established in 2007 by Stanford University Professor Gretchen LeBuhn as a way to involve citizens in the monitoring of pollinators in their backyards. The project has grown to more than 100,000 volunteers across North America and has generated invaluable data about the distribution of bees and other pollinators across the continent, and the effects of pesticides on pollinators.
(2b) Squash bee counts
Squash bees are a native bee that is the best pollinator for pumpkins, squash, zucchini, and other members of the cucurbit vegetable family. These solitary bees are ground nesters and generally represent a fairly healthy ecosystem. To quantify the abundance of squash bees, we will examine 100 flowers and count all squash bees that are present, with five repetitions per field. To be comparable, this experiment will take place in the second week of August across the province, between 8:00 – 9:00 AM.
(2c) Walking transects
In contrast to stationary observation, it is also possible to survey a greater area if a travelling observation approach is utilized. With this approach one can walk through an environment of interest, stopping at predetermined time intervals, target a particular flowering plant across space, or one can scan the flowers while walking and stop for observation when a pollinator is detected.
(2d) Photography
Pollinators are beautiful and extraordinary creatures! As such, they make wonderful subjects for avid photographers. Though it can be challenging to capture the perfect image of small insects on the move, photographs can be invaluable resources for identifying pollinators. Participants can target a focal group of pollinators or plant species, or can combine photography with a standard observation monitoring protocol, but photographs will be aggregated and an expert entomologist will assist when needed to identify the species captured in the images.
(2e) Microscopy & traps
By enhancing a smartphone with readily available lenses, participants will construct their own microscope for approximately $10 and half an hour of shop time. Participants can then set up a small insect trap and take magnified photographs of the specimens in the trap. Such “kill-based monitoring” is the only method that can also quantify nocturnal and very small pollinator species which are not observable visually. Based on your photograph, internet websites exist that help you identify your pollinator species. This monitoring option is most suitable for ambitious science classes.
(2f) Group specific monitoring
Plants are pollinated by an incredibly diverse and beautiful suite of insects: ants, bees, beetles, butterflies, moths, and wasps all contribute pollinator services to a variety of flowering plants, shrubs, and trees. However, not all species provide the same degree of pollinator services to plants, and different pollinators exhibit preferences for pollinating particular types of plants. Furthermore, pollinators may also vary in the time of day and temperature range within which they will fly, as well as the distances they will fly, and the resources they are gathering from plants. Participants with an interest in a particular group of pollinators may choose to monitor and observe that group in particular. Depending upon the group of interest, participants will need to target the plant species observed as well as the time of day of the observations, depending upon the focal pollinator group being monitored. This allows an individual to gain a deeper knowledge about one particular component of the pollinator community, and may also allow for more specific levels of identification than possible when observing all pollinators.
If nesting habitat is available, it may attract pollinators from the surroundings who are looking for nesting space and find that material adequate. The colonization of empty habitat indicates that there is a population seeking it, either because they expanded, or because they were displaced from other habitat. By providing a number of nesting spaces and monitoring the colonizing species, we can learn about the diversity and abundance of pollinators.
(3a) Bumble Bee boxes
Bumble bees have been shown to dramatically improve pollination for a number of vegetable crops grown in greenhouses—particularly tomatoes—but these commercial pollinators harbour diseases that native bumblebees are susceptible to. Bumblebees are fairly flexible in their choice of nesting locations; they seek a roughly shoebox sized cavity, and will often establish nests in old rodent burrows, or in clumps of tall grass that have dried and toppled in the fall. However, bumblebees can also be coaxed into using a variety of human created nest boxes that can also allow for nest observation and monitoring. By constructing and monitoring artificial bumblebee nest boxes, it allows an unprecedented opportunity to observe bumblebee nest development throughout the season of the colony. It also allows for the possibility of identifying the bumblebee species present and nesting in the area, and allows for monitoring for the endangered rusty-patched bumblebee.
Booklet: Pollinator Management For Organic Seed Producers
Authors: Eric Mader and Jennifer Hopwood, Xerces Society. In 22 pages, this excellent booklet summarizes what vegetable growers should know about pollinators in their field. Targeted to seed producers, it provides colourfully illustrated descriptions of pollinators and crop-specific considerations, such as separation distances for breeding.
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Booklet: A Landowner’s Guide to Conserving Native Pollinators
Author: Susan Chan, Farms At Work. As one of Ontario’s leading pollinator experts, Susan Chan summarizes bee biology and measures to protect native pollinators in our province. This booklet contains rich tables on local plant species and their foraging season, as well as local sources for native plants. The booklet can be obtained through the Canadian Organic Grower for $10.
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Book: Attracting Native Pollinators: Protecting North America’s Bees and Butterflies
Author: The Xerces Society. In 380 pages,
Attracting Native Pollinators provides everything that you may need to know about creating and managing pollinator habitat. The book also contains illustrated descriptions of pollinator families and native plants. In Canada, it is distributed through Lee Valley for only $23. We highly recommend this book as the most thorough but accessible information source.
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The impact of neonicotinoid pesticides on pollinator population health is widely discussed. While not the focus of this project, we recommend these reads who attempt a balanced perspective:
Are Neonicotinoids Killing Bees?
By The Xerces Society. This booklet summarizes scientific facts about neonicotinoids and pollinators, and recommends actions to minimize their exposure. We find this booklet is one of the most balanced and scientifically robust sources in this highly emotional debate.
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Sub-lethal exposure to neonicotinoids impaired honey bees winterization before proceeding to colony collapse disorder
By Chensheng LU, Kenneth M. Warchol, Richard A. Callahan.
Bulletin of Insectology 67(1): 125-130, 2014.
This academic paper is the first peer reviewed study that clearly links the colony collapse disorder with minute doses of neonicotinoid pesticide.
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Evaluation of Canadian bee mortalities in 2013 related to neonicotinoid pesticidesHealth Canada Interim Report. Available online:
Visit Website >>
Several insect guides are available in print and online. For us, the following stick out:
Bug Guide.
This geeky, but excellent, website is dedicated to insects and other arthropods and provides a free identification service. The website describes itself as an “online community of naturalists who enjoy learning about and sharing our observations of insects, spiders, and other related creatures”.
Visit Website >>
e-Butterfly.
This website provides information and resources for North Americans who want to discover and share images, distribution maps, and other information regarding butterflies in North America.
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The Bee Genera of Eastern Canada.
This article provides descriptions and keys to the bees of Eastern Canada. Authors: Packer, L., Gernaro, J.A., and Sheffield, C.S. Canadian Journal of Arthropod Identification No.3. 2007. doi: 10.3752/cjai.2007.03.
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The Bees of the Eastern United States.
This book by Theodore Mitchell provides detailed information regarding all North American bee species. It has been made available online as a series of pdfs free for download from North Carolina State University’s Insect Museum website.
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Bee Photography Guide.
This site provides tips and tricks for taking photographs of pollinators.
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Hi Resolution Bee photos.
U.S. Geological Survey
Visit Website >>
Pollinator Guelph.
Pollinator Guelph maintains a well-organized and up-to-date list of pollinator resources, which include resources for teachers, videos, and countless good links.
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Xerces Society.
International, nonprofit organization that protects wildlife through the conservation of invertebrates and their habitat.
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Resources for educators: Curricula. Visit Website >>