The pollinating insects: essentials
Ana María Pujante Mora
Since plants cannot move, they have developed mechanisms of reproduction by spreading pollen to other plants. To do this, they have established very close relationships with many animals, mainly insects, which help them transmit their genetic material. The pollen contains the male gametes, it travels attached to the legs and the body of the insects to the female organs of other plants. The pollination that animals make possible is called zoophily.
Within the animal world, insects carry out most of the pollination: Diptera (flies, mosquitoes), Lepidoptera (butterflies, moths), Coleoptera (beetles) and mainly the Hymenoptera group (bees, bumblebees).
The honeybee (Apis mellifera) is the most efficient pollinator and the most threatened. Concern about declining bee populations has left us with headlines like these: “Imagine a world without bees” or “What would happen if bees disappeared?”
In the surroundings of Aras, it is common to find beekeepers’ hives, of great importance for the local economy. Each hive counts from 15,000 to 80,000 individuals depending on the time of year. It is estimated that a single bee usually visits 7,000 flowers a day and 4 million visits are needed to produce a kilo of honey. Western honeybees, including those from Aras and Losilla, can produce 1.6 million tons of honey a year.
Main threats to pollinators
There are many threats that have led to a drastic reduction in wild and domestic pollinators, such as the honeybee:
- The loss and degradation of habitats. Intensive monoculture agriculture and changes in land use imply a reduction in the diversity and abundance of pollinator populations, by producing a limitation in the availability of food (flowers) and nesting and refuge places.
- The use of phytosanitary products. The use of insecticides, herbicides, fungicides and fertilizers, and their improper use, can cause the death of pollinators. In some cases, in the European Union (EU), the use of neonicotinoid insecticides has been restricted or prohibited, which has produced CCP syndrome (bee colony collapse), causing the death of both domestic and wild bees.
- Pathogens and diseases. Since the 1980s, one of the main threats to honeybees is a disease called varroosis caused by the Varroa destructor mite, an allochthonous ectoparasite that reproduces in the larvae and pupae of hives. In addition, the mite weakens the bees and makes them vulnerable to virus attack.
- The presence of invasive species. The Asian hornet or killer wasp (Vespa velutina) was detected for the first time in Spain in 2010, spreading rapidly throughout the North. The monitoring of its expansion (avispaasiatica.org) indicates that it will have colonized the entire Peninsula by the end of the decade.
- Climate change. All pollinators are affected by spatial and temporal imbalances between insects and plants, by the virulence of pathogens, local mortality from extreme weather events, and the better adaptation of invasive species to these changes.
Two years ago, on September 21, 2020, the National Strategy for the Conservation of Pollinators was approved. This strategy points out the importance of zoopollination, or animal pollination, estimating that food crops depend 75% on it. To prevent the decline of pollinators, the EU has set a target of devoting 25% of EU agricultural land to organic farming (EU Pollinators Initiative) by 2030.
Necessary measures to save pollinators
The necessary measures to avoid the decline of bees and pollinators are summarized in:
- Identify and conserve the populations of most threatened pollinators. In 2014, the Red List of Bees in Europe was published, in which it is concluded that 9.2% of bees in Europe and 2.6% in Spain are threatened. It is important to identify which species are most threatened to adopt the measures that guarantee their conservation.
- Identify important habitats for pollinators, particularly those included in the Habitats Directive, and design and apply measures to conserve the habitats of the most threatened pollinators, such as including requirements for pollinator habitats in management plans of protected spaces.
- Conserve pollinators and their habitats through green infrastructure. The presence of ecological corridors, the interconnection of habitats and the declaration of protection zones must be integrated into strategies and planning at the national, regional, and local levels.
- Prepare and disseminate a manual of good practices in agriculture for the conservation of pollinators and promote the development of measures specifically in the Rural Development Programs. An affordable measure for small populations such as Aras and Losilla is to promote the presence of multifunctional margins, islands of biodiversity, bordering floral margins, slope conservation, which are essential for the survival of most pollinating insects.
- Promote the use in beekeeping of the native breed, Apis mellifera iberiensis, and its local varieties and ecotypes for the conservation of genetic diversity. Study ways to improve the marketing of bee products obtained from native bees and promote campaigns to promote organic bee production for its contribution to the conservation of pollinators.
- Monitor the appearance of the main diseases and other threats to bees and control the transmission of pathogens between wild and domestic pollinators, as well as encourage measures to control and treat the main diseases of pollinators.
- Reduce the risk derived from the use of phytosanitary products for pollinators. Promote training on the use of phytosanitary products and awareness campaigns on their sustainable use and the risks to pollinators. Reduce the use of phytosanitary products on land owned, owned, or managed by the public.
- Support research to improve knowledge of pollinators.
- Promote and support initiatives developed by organizations, foundations, associations, and companies that contribute to the conservation of pollinators.
Pollinators are a key biological group for the conservation of biodiversity, the preservation of primary production and for human consumption. The UN declared May 20 in 2017 as “World Bee Day“, to raise awareness about the importance of pollinators, the threats they face and their contribution to sustainable development.
Its conservation requires the participation of all: citizens, businessmen, conservation organizations and scientists. Although they are our smallest neighbors, we must not forget that without insects, and especially pollinators, we would not be here. It is our duty to help them continue to care for the world we share.