Nutritional complementarity of cultivated and native plants for bumblebees
Monocultures restrict pollinators to a monotonous, often deficient diet, increasing the risk of disease and reducing pollination and reproductive performance. We seek to identify the best combinations of plants (cultivated or cultivated-indigenous) providing a nutritious pollen resource adapted to bumblebees over an annual cycle, in order to target the combinations to be favored in agricultural environments to fight against malnutrition and decline of wild bees.
We will identify pollen from cultivated or native plants with high nutritional value and with medicinal potential for bumblebees, and assess their complementarity with the main crops in Eastern Canada (corn, soybeans, blueberries, cranberries, apples, strawberries, tomatoes).
We are conducting studies in a controlled environment (animal house), semi-controlled environment (greenhouses) and in the wild (field), in which we seek to evaluate the benefits of different pollen (tested individually and in combination) on the health, reproduction and survival of several bumblebee species.
Blueberry field - area where the habitat is dominated by blueberries, which bloom in June and are very attractive to bumblebees. However, its flowering is short and does not provide all the nutrients necessary for the health and performance of the colonies.
Corn - its cultivation is widespread in Quebec, especially in Montérégie. Although widely pollinated by wind, corn, which is generally cultivated over very large areas, is heavily visited by pollinators during its flowering. However, it is deficient in some essential nutrients affecting behavior and reproduction.
We will also carry out biochemical studies on each pollen, in order to measure their content in various essential nutrients for native bees.
Course of studies
April 2021 - We initiated a study, in collaboration with Wildlife Preservation Canada, on the benefit of pollen from trees native to Quebec and Ontario on the reproduction and health of queens of two species of bumblebees natives of these Provinces.
This study is an integral part of WPC's native pollinator initiative, in which queens of different species are bred under controlled conditions and then released to support declining wild populations.
(c) Sarah MacKell - WPC
May 2021 - Bumblebee queens were captured in southern Ontario and placed in the animal facilities of the African Lion Safari where the study is conducted. We will test the benefit of pollen from three different species identified as having high nutritional values for bumblebees, compared to a mix of wild flower pollens.
The pollens were obtained thanks to our collaborators , Yann Loranger and Isabelle Rabbat.
July 2021 - here are some pictures of the growing colonies!
Installation of queens in the animal facilities under red light - why? Because bumblebees do not see in the red, allowing to recreate a dark environment like their burrows in the wild. (c) Sarah MacKell, WPC.
Queen Bombus impatiens with her workers. Do you know how to identify young emerging individuals? Their hair is still white, and will take on a yellow color over the hours / days, while their abdomen will turn black. (c) Sarah MacKell, WPC.
Queen Bombus griseocollis with her two new workers, taking care of the brood. Colonies of this species are generally smaller in size than those of the species Bombus impatiens.
Improving bumblebees' health in greenhouses to preserve wild pollinators
Commercial bumblebees are used on a large scale for the pollination of greenhouse crops. However, they are less resistant to disease, and thus pose an additional threat to wild bees, by increasing the transmission of parasites. We want to test to what extent the establishment of sunflower strips, the pollen of which has medicinal values, in greenhouses in Quebec operates as a simple and effective solution to reduce the parasitic load of commercial bumblebees before they enter. contact with bumblebees and other wild bees.
Ruche commerciale de bourdons (Bombus impatiens) pour la pollinisation des cultures en serre - (c) Mathilde Tissier
Course of the study
April 2021 - identification of participating greenhouses and installation of the first beehives
May 2021 - monitoring of the hives in each greenhouse by non-invasive capture of the workers (collection of excrement to assess workers' health), before releasing them into the greenhouse
June 2021 - Sunflower transplants in greenhouses and monitoring of beehives
July 2021 - Introduction of new hives in greenhouses during the peak of flowering and non-invasive monitoring of workers
Some pictures of the study
April 2021 - worker from a commercial beehive - (c) Mathilde Tissier
July 2021 - worker on a sunflower - (c) Mathilde Tissier
July 2021 - 5 bumblebees on the same flower! It is a worker and 4 males. How to differentiate them? Males do not have a pollen basket on their legs (and they have one more segment on the abdomen) - (c) Mathilde Tissier