The presence of wild pollinating insects on livestock farms, associated with the maintenance of areas with spontaneous vegetation and hedgerows (preferably with native species), provides ecological services, such as biodiversity and pollination activity, which enhances better production and variety of pastures and quality of crop harvests.
Strategies such as insect hotels, creation of flower or unmown vegetation strips, increase of auxiliaries like birds and bats, can enhance farm biodiversity without the need of large investment.
Most plants, including grasslands, depend on pollinating insects for their production. Favouring wild and domestic pollinating insects is part of good agricultural practice. Maintaining their populations improves productivity and reduces the use of chemicals (pesticides, etc.). A balanced pollinator population allows farms to be more resilient to climate change and to maintain a rich seed bank.
To this end, it is recommended to: allow hedges to remain with non-agricultural floristic species, as well as trees of different species and ages; promote ungrazed areas, woodlands and natural hedgerows; limit the use of agrochemicals; create dispersed water points; allow decaying woodpiles to exist and maintain stone buildings or walls. Related to this last point, where there are few natural cavities, the most commonly used strategy is to provide shelters for some groups of auxiliary fauna. These shelters can be bird nest boxes, bat boxes, insect shelters (also known as insect hotels), mammal shelters or amphibian and reptile shelters (which can be simply constructed from stones and wood). These shelters promote biological balance in the ecosystem, allowing self-regulation. In other words, sustainable agriculture is achieved by promoting useful fauna that prevents the excessive growth of harmful species, thus achieving self-regulation in a natural way.
In particular, insect hotels are mainly made of wood. They have several parts inside the hotel with different features, allowing attraction of different insect species. Several materials can be used according to the different wishes of each insect species, as pinecones, wood with holes, driftwood, bark, shavings, bricks, or stones. For instance, solitary bees and wasps take advantage of holes in the wood to create an imitation of the natural galleries previously dug by other insects in these artificial hotels.
The main benefits are an increase of global biodiversity, grassland and crop productivity and lower need of pesticides.
The main challenges are to slightly reduce pasture or cultivated area to create spontaneous strips of vegetation, and costs for planting and/or maintaining hedges or flower/vegetation strips, also to prevent potential fires. Moreover, these practices can be implemented in a short time, but their effects may take a few years to maximise.
Key success factors for insect hotels are: implantation near water access, placed between 60 and 100 cm high, sheltered from wind and rain, in a place out of direct sunlight on summer afternoons, and away from pesticide applications. Four main lessons learned by insect hotels implementation are: 1. The insect hotel installation only provides shelter for insects, but not food, that’s why it is important to maintain a strip of flowers or spontaneous vegetation. 2. Too large insect hotels designed for several species can favour the transmission of parasites between them that is why it is better to favour small hotels designed for specific species. 3. Insect hotels are also an educational and communication tool to show the importance of insects. 4. The proliferation of insects also attracts other auxiliaries such as birds and bats that can eliminate crop pests.
Impact on socio-economic resilience
Positive impact on grassland and crop productivity.
A lower need for pesticides.
Few costs for insect hotel construction, but a few costs to maintain hedges or vegetation strips.
A small reduction of the production area to create unmown vegetation strips.
A better communication to consumers thanks to visible insect hotels, which could be educational tools.
Impact on environmental sustainability
Increase in the number of pollinating insects.
Increase of global biodiversity.
Footprint reduction thanks to a lower use of external inputs.
Increase in biomass accumulation areas and storage of carbon in the soil thanks to vegetation strips implementation.
Audio-visual material
Insect hotels: https://youtu.be/3dLYIdbR8YU, https://youtu.be/6PW5w8KpFLo and https://youtu.be/8IPSL5q16p4
Helping Pollinators on your farm, Scotland’s Farm Advisory Service: https://www.youtube.com/watch?v=KFWjqP5cNqQ
Farmer comment
Organic farm Cortijo el Puerto de Lora del Río (Sevilla, Spain): https://youtu.be/HWjq-Bs207o
Further information
Favouring pollinating insects on farms (LIFE LiveAdapt):
Biodiversity and pest control with nest boxes and insect hotels in olive and almond farms (LIFE Resilience): http://www.liferesilience.eu/
Biodiversity in Dehesas (LIFE Montado-Adapt):
https://www.lifemontadoadapt.com/index.php?n=526
Shelter or "Insect Hotels" (Instituto de Investigaciones Agropecuarias, Chile):
Pilot experience: An insect hotel to shelter insects for natural pest control (Agroinformacion.com): https://agroinformacion.com/experiencia-piloto-un-hotel-de-insectos-para-cobijar-a-insectos-para-el-control-natural-de-plagas/
La Granja de Bitxos: https://www.lagranjadebitxos.com/es/hoteles-de-insectos-para-que-sirven/