1. What’s is the ‘OSMIA Initiative’
The Osmia project arose from the ADV Ecològica de Ponent in 2017, the result of the need to find natural pollinators for fruit trees with flowers that are difficult to pick. The first tests with Osmia were done on white pear variety, and the obtained results were interesting. As we studied them, we realized that these wild bees had decreased in population over the past few years. Since then, we have launched our own breeding of Osmia cornuta which is expanded annually and distributed among interested partners.
1.1. Project objectives
The Osmia Project focuses on:
- -Increase the natural populations in all territories where we have influence to recover the populations that were there in the past.
- – Improve the autonomy of farmers in terms of pollination and that they incorporate bees as an indispensable element in the management of their farms.
- – To introduce the wild and solitary bees of the genus Osmia and spread the word about their current status.
1.2. Goals achieved so far:
Thanks to the installation of Osmia shelters in the fields, we have achieved:
- – Create and miltiply ADV osmia breeding each year to support pollination and increase populations.
- – Carry out pollination tests on woody crops such as pear, almond and apricot.
- – More than 19 Osmia breeding points in the Ponent’s regions: La Granja d’Escarp, Pla de la Font, Palau d’Anglesola, Almenar, Vilanova del Segrià, Vilanova de Bellpuig, Ibars D’Urgell, Os de Balaguer, Vilanova de la Barca, Cogul, Bovera, El Poal, Alfarràs, Juneda, Maials, Lleida, Arbeca, Vinaixa, Tàrrega
2. Do you want to know more about Osmia?
2.1. What are Osmia?
Within the large group of bees, the best known is the honey bee (Apis mellifera). The rest of the bees are called wild. In Spain, the ratio is one honey bee for every thousand wild bees.
Osmia ara a group of solitary wild bees that have gone unnoticed in our agricultural environment while they were in charge of pollination and the production of a multitude of fields. They feed on the pollen and nectar of fruit trees and other seasonal wildflowers. They build their nests in holes separated by cells. Each species has its particularities: some make their cells with leaves and others with mud, some make their nests in holes and others in snail shells…Like other solitary bees, they are quite docile, do not attack and if they do get stung, it’s not very painful.
Several studies show that bee populations are in decline and that there are even species in danger of extinction. The main causes are the urbanization of the fields, the introduction of new species, climate change and the use of pesticides.
One of the most interesting species in woody crops is Osmia cornuta due to its predilection for flowers at a certain height, but there are hundreds of other species of the genus Osmia that also need to be preserved.
2.2. Osmia cornuta
The adults of Osmia cornuta emerge at the end of January, the males first, who will stay near the nest waiting for the females. They differ from females by being slightly smaller and having a white patch on their heads. When the females emerge, mating will take place. The males die soon after, and the females are responsible for occupying and supplying the nests until April.
To do this, it accumulates pollen, which it mixes with nectar and saliva, in the cane that will be its nest. It will need ti visit many flowers to collect enough pollen and nectar for a brood. Once she does, she lays an egg on the pollen mass and builds a septum. Repeat the same process until the entire cane is completed. The final partition is thicker and stronger than the previous ones. Then, if she still has time, she search another hole and starts another nest. The larval and pupal stages take place from April to January. They leave the cane in the adult phase, at the end of January and repeat the cycle.
Usually, they made shelters in brick walls, but the limited presence of these constructions in rural areas and the dissapearance of this construction technique in urban areas have contributed unfavorably to their availability of shelter.
Osmia cornuta is not exempt from the impacts derived from human activity, and its population has also suffered a decline in recent times.
3. Collaborate
Do you want to help with the Osmia Project? You can do it in different ways:
- – Taking care of the landscape. If you still have a brick warehouse, standing or half-demolished, do not throw it on the ground. This is a vital refuge for the survival of wild bees.
- – Try to maintain flower margins or spontaneous flowers in the environment to provide food for the bees.
- – You can build shelters with reeds, wood or similar and hang them near areas where you see them flying to increase already existing populations. They must be hung in January and if they are reeds they must be very dry. If you don’t have time, you can buy some.
- – You can help us and volunteer with us. The development of shelters and their sanitation takes a lot of work. If you are younger than 30 years old and you are enrolled in the Youth Guarantee program, we are looking for young people during 6 months for this job. If you are interested, send us an e-mail at osmia@advecologica.org
- – You can donate to the Project and help to be able to buy material for the shelters and thus help keep the project alive. With your collaboration, we give you a gift by giving you a shelter made by us in order to start your breeding (between December to January) until stocks last. Send us an e-mail and we’ll tell you how to do it.
3.1. What do you need to know if you place a refuge?
Before placing it. How and where?
- – It’s `preferable that the area where you place the shelter has flowering plants (aromatic, fruit trees…)so that they have food.
- – Females use mud to build shelters. If there are no water points near the shelter from January to May, you can provide them yourself in a glass.
- – They love to fly at a certaing height, so the shelter should be at least 1m high.
- – It’s important that the shelter is well fixed to avoid shaking. Some examples are: embedded in the branches of a tree or stuck under the roof.
- – Preferably, the shelter is oriented with the reeds in a southeast direction, facing the rising sun.
- – The size of the cut canes should be between 13-15 cm lenght. The reeds are grouped in a horizontal position with the knot located at the back of the shelter.
- – The reeds must be very dry and clean inside. Moisture is a trigger for fungi and other diseases, while dirt can compromise the choice of cane by the female. It’s recommended to cut them during the summer and leave them to dry until January, when it’s time to use them.
- – To extend the life of the refuge, you can cover the wood with some material that shelters it. Of course, it’s advisable to avoid toxic products because bees are very sensitive to them.
Once placed, now what?
The early males of Osmia cornuta already start to emerge from the cocoons at the end of January. And the late females live until April-May. In this period, the males will ferilize the females. Females nest near where they were born, so it’s essential not to move the shelter once they have hatched from the coccoon or they could become disoriented. During this month is when we will be able to see them fly.
Covered reeds are the indicator that a female has occupied it to nest. In April or May, when we see them covered, we can collect them to store them in a space protected from rain and parasites, but that’s not heated. It is crucial that they are in stable conditions that respect the temperature of the time of year, especially in winter. The heat in the cold months can advance the hatching of the cocoons causing them to be born in unfavorable conditions due to the lack of food and frost.
In January, the covered canes must be returned to the field. Before they come out of the cocoons, you can place them in another place; but once they are born, they must not move. Although it is also possible to keep the shelter with the canes in the field throughout the year. In this case, it is possible that other later Osmia species (such as Osmia tricornis) can occupy the reeds that have been left empty. There is no downside, you will have given shelter to more species!
If all goes well, the population will triple every year. If you want to increase your population , you can place another refuge next to it with empty reeds. The cocoon room is no longer needed, so you can take advantage of the space and replace it with new reeds.
Bees and agriculture must go hand in hand!
