The Human-Made Impact on the Bee’s Lives
Insect pollinators are a key element for the equilibrium of the ecosystems that surround us, and bees are an important subgroup because they are responsible for pollinating around 60 to 70 percent of the world’s total flowering plant species. However, extinction rates have jumped from 100 to 1,000 times the normal rates because of many external conditions, like climate change, urbanization. At this point, the questions are the following: is the importance of these little insects clear to our society? And, are any measures being developed to avoid these risks?
Insect pollinators are a key element for the equilibrium of the ecosystems that surround us. According to the Food and Agricultural Organization of the United Nations (FAO), around 75% of the world’s crop-producing fruits and seeds for human consumption are dependent, at least in part, on pollinators. But what is pollination? In simple terms, pollination is the movement of genetic material in the form of pollen grains that come from the male reproductive part of a plant to the female reproductive part of a plant. Upon the two’s meeting, a plant’s seed or fruit is formed. Some plants can pollinate themselves, while others need the help of abiotic agents such as wind and water, or the help of animal pollinators. Among these animal pollinators are bees, which are very efficient pollinators due to their ability to communicate the location of flower resources to their nestmates.
Bees are an important group of insect pollinators because they are responsible for pollinating around 60 to 70 percent of the world’s total flowering plant species, and this is crucial in maintaining biodiversity. Without pollinators, many plants could not seed and reproduce; and without plants to provide pollen and nectar, many animal populations would decline.
Pollinator-dependent crops are five times more valuable than those that do not need pollination. Consequently, the European honeybee, Apis mellifera, is one of the most economically valuable pollinators of crops worldwide. This species is found in a wide variety of environments, and in fact, it is a species that has shown great adaptive potential. This last characteristic is fundamental when we witness the effects of climate change.
Caption for picture: European Honeybee, Apis mellifera.,
According to FAO, extinction rates for pollinators have jumped to 100 to 1,000 times the normal rates. Approximately 40% of invertebrate pollinators such as bees and butterflies are facing extinction worldwide, but especially in Europe and North America. This decrease may be caused by many factors such as parasites, bacteria, viruses, pathogens, evasive species, climate change, and, lastly, urbanization. However, in the future, climate change is expected to have a major role in the decline of bee populations worldwide, due to both changes in temperature and general meteorological conditions.
Climate change can influence honeybee’s behavior and physiology, it can alter the quality of the floral environment and increase or reduce colony harvesting capacity and development. Due to changes in temperature and meteorological conditions honeybees may migrate to places where the conditions are more favorable, which may destabilize the competitive relationships among different species and races, as well as among their parasites and pathogens. The environmental implications of climate change will also influence apiculture methods, forcing beekeepers to adapt.
Apis mellifera has the potential to adapt to hot climates. This characteristic is most likely advantageous to their adaptation to the expected increase in the average global temperatures that are anticipated for the next decades. In cool regions, honeybees spend the winter clustered in a tight ball and use their honey stores to provide them with energy during the hibernation period. In the spring, the queen starts to lay eggs, and the colony size increases. However, a sudden but long cold may occur during which the honeybees are unable to harvest. The increase in the workforce causes the last rations of honey to disappear quickly, which consequently may cause the colony to die of starvation. This inability to adapt is quite common with hybrid bees (crosses of several races by bee breeders), whereas local ecotypes are much better adapted to the environmental conditions and with the start of spring develop more slowly.
A major effect of climate change on honeybees comes from changes in the distribution and development of flower species on which the bees depend for food. For example, when acacia blossoms are washed by rain, they become unattractive to honeybees because the excess water dilutes their nectar too much. Alternatively, lavender flowers produce no nectar when the weather is too dry. Bees will abandon areas that evolve towards drought and migrate towards the margins of such areas. In contrast, honeybees will colonize cold areas that were at first hostile to them. For example, the Africanised honeybee’s geographical distribution has moved as far as Argentina and the USA. Therefore, global warming will cause bees to move to geographical areas that were not favorable initially, and bees that adapt more easily are the ones that will most likely persist.
Caption for picture: Acacia flower
Other species that will suffer greatly because of climate changes are the bumblebees. If climate conditions change more frequently than the species’ historically observed tolerances, their occupancy and richness will decline. Temperature and precipitation can have direct and indirect effects on bumblebees; directly affects the species’ mortality and fecundity, indirectly changes the floral resources. According to a study on pollinator decline, the probability of site occupancy has declined on average 46% in North America and 17% in Europe relative to the period between 1901 and 1974.
Caption for picture: Bumblebee
Another aspect that is worth mentioning is the bees, especially honeybees, impact on economics. According to FAO, the volume of agricultural production dependent on pollinators has increased by 300 percent between 1968 and 2018. Cocoa and coffee are two examples of crops produced with pollination, and these provide income for family farms, especially in developing countries. Moreover, with the increasing commercial value of honey, bees are becoming a growing generator of income. The value that bees bring to humans is beyond the food that we eat. Some species provide materials such as beeswax for candles and musical instruments.
As previously mentioned, urbanization has an impact on the lifespan of bees. Nevertheless, this impact is not straightforwardly negative. City parks and little gardens on apartment balconies provide bees with diverse pastures throughout the year. Urban beekeeping is valuable for the environment because bees take care of natural ecosystems. This contrasts with monocultural practices that are one of the worst threats to wild bees because they do not promote biodiversity.
While beekeepers and farmers can protect bees that are important for their economic activities, such as honeybees, they can endanger wild species with their practices. Hence, it is essential to protect bees, but especially wild bees, because they enrich biodiversity on our planet, and I believe that in the future a stronger relationship between conservation in urban and rural areas will be necessary.
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