Reports of the bee community dwindling across the world have set alarm bells ringing for entomologists, apiculture experts, and scientists alike, for bees are vital for the health of the planet. It is high time we stopped taking them for granted and paid serious attention to checking the decimation of their populations. TreeTake takes a look …
They work very hard but need scant attention. Bees, though tiny, are nothing short of being nature’s superheroes. They play a crucial role in pollination. Of all creatures, bees are the most dominant pollinators of wild and crop plants, visiting more than 90 percent of the world’s top 107 crops. Bees even help plants survive by preventing inbreeding. They are an important part of bio-diversity, providing honey, royal jelly, and pollen and products such as beeswax, propolis, and honey bee venom.
But sadly, the bee population across the world is on the decline, raising serious concern among entomologists, apiculture experts and scientists alike. According to a report, from April 2018 –April 2019 April, the bee population decreased by 40.7% in the U.S. and a similar trend was noted throughout the globe. In India, several types of bees are found, including Apis mellifera, Apis dorsata, Apis, Apis cerana Indica, Apis cerana Apis florea, carpenter bee, Apidae, Bumblebee, Stingless bee, leafcutter bee, Tetrgonula iridipennis etc. As per another report, more than 40% of honey bees disappeared during the past 25 years in India.
The International Union for Conservation of Nature (IUCN) lists 16 species of bees as vulnerable, 18 as endangered and 9 as critically endangered globally.
Why are bees endangered?
Bees are at risk of extinction largely due to human activities: large-scale changes in land use, industrialised agricultural practices like monocultures, and the detrimental use of pesticides have all contributed to destroying their habitats and reducing their available food sources. Globalisation has also facilitated the transmission of parasites and other invasive species that prey on bees, like the Asian hornet, which can decimate entire hives in hours. Habitat loss and habitat fragmentation, changes in land use, including insensitive urban development and intensive farming have caused significant loss of bee-friendly habitat, resulting in the loss of diverse food sources they need. Urban concrete jungles, cemented roads and buildings allow very little space for flowers, grasslands, and fewer sufficient places for bees to build their hives which significantly causes habitat loss. Habitat fragmentation disrupts the bee from finding mates, and building hives and reduces the gene flow in the bee population.
Ankush Dave, ecology conservator, also known as Tree Man of Agra, while citing the example of his own farm, said: “I have seen on my farm that the leafcutter bee cuts fresh leaves of two types of Grewia (falsa tree) and rolls it to make nests in the earth to lay its eggs. Its natural habitat is made from cutting Grewia leaves. The tree gets fresh leaves in May and June and then the bee cuts only fresh leaves, not old ones, and makes its nests. This system that insects follow has been continuing since time immemorial. Their schedule is set and their lifecycle is also dependent on that. Besides, some bees make hives on unplastered walls. But in how many places do you find Grewia trees or unplastered walls for that matter? Some bees may also have a habitat in dead wood or leaf litter. But where are such things left? Leaf litter is removed to make fertilisers. Similarly, carpenter bees make a nest in bamboo on my roof and sometimes in fallen wood. But in how many places would they find bamboo or dead wood? Wild bees’ habitats are like that. But most dead trees are felled and dead wood is swiftly removed. Bees are important pollinators and if they decline, forests will also be degraded. So, attention should be paid to their habitat protection.” “Stingless bee prefers white flowers and makes hives on unplastered walls. Nonavailability of both these things is bound to have an adverse effect,” he added.
“Earlier, we planted more of flower and fruit-bearing trees of mixed species which flowered at different times throughout the year but now we go for monocultures, even in forest interventions which do not give pollen throughout the year,” said Prof Venkatesh Dutta of Babasaheb Bhimrao Ambedkar University, Lucknow. He said a decline in water bodies was also responsible for the dwindling population of bees.
Climate change poses increasing threats to bees. Global warming and extreme heat waves cause the decline of this organism. Not only extreme heat but also events such as storms, floods, and drought have a major impact on the bee community. For instance, flooding is likely to harm many bee species that nest underground. An extremely dry climate can reduce pollen production and a pollen diet is very important for rearing the future workers. A pollen shortage induced by drought can weaken the immune system, making them more susceptible to pathogens. “They will not tolerate high temperatures in the month of May and June or extreme winter cold,” said Dr RK Singh, entomologist and dean, Chandrashekhar Azad University of Agriculture, Kanpur. “Bees leave their hives in the morning and return at sunset. If the temperature runs high in the afternoon, they suffer heatstroke like humans and die. Rock bees are a little resistant to extreme temperatures but Apis mellifera and Apis melipona are not,” said Dr Singh.
Pesticides and insecticides are also detrimental to bees, feels Dr Singh. “Bees visit mustard fields in the day and if the farmer has sprinkled a contact insecticide like malathion, they come in its contact and die on the field,” he said. Insecticides like neonicotinoids are absorbed by plants and can be present in pollen and nectar, making them toxic to bees. These are also associated with bee decline. They also have an adverse impact on the navigation, immunity, feeding behaviour, and reproductive physiology of bees. According to a study, Clothianidin, Imidacloprid, Thiamethoxam, and Dinotefuran are highly toxic to honey bees and bumblebees.
Individual bees can be exposed to environmental stressors at different ages. If bees cannot bear the stress both the hive bee and forager bee populations will decrease. Young bees start foraging before the usual age which can cause physical alterations to the brain that may reduce their ability to remember things needed for proper foraging leading to disorientation and less efficient food gathering. This ultimately leads to colony collapse.
Numerous pests, parasites, and pathogens (protozoa, bacteria, viruses) prey upon honeybees and sometimes trigger colony collapse disorder (disappearance of the majority of worker bees in a colony).
Varroa mite (pest of the honey bees) attaches itself to the body of the bee and weakens it by sucking fat bodies. It weakens the bee’s immune system and encourages viral growth. It is linked with the death of around 27% of the hives during the winter, as per a 2010 report. RNA virus Israeli Acute Paralysis Virus can cause acute paralysis to the members of the Varroa mite-infested colony. Varroa mite is the vector of this virus.
Gut parasite Nosema
Gut parasite Nosema infection impairs midgut integrity and alters the energy demands in honeybees. The infection also significantly suppresses the bee’s immune response and modifies pheromone production in worker and queen honey bees leading to precious foraging. N.Apis is well known to the bee community but N.Cranea is recent in western honeybee colonies which can kill bees faster than N.Apis. Nosema cranea is associated with a sharp decline in honey bees in Spain.
The bacteria which are pathogenic to honeybees attack the brood.
Colony Collapse Disorder
Colony collapse disorder, which was first observed in 2006, causes bees to mysteriously abandon their hive. Affected colonies have experienced mortality rates as high as 90%. A U.S. Department of Agriculture and Environmental Protection Agency report issued in 2013 suggests a complex mix of problems contributing to honeybee colony declines. Contributors include parasites and disease, genetics, poor nutrition, and pesticide exposure, as well as unsustainable farming practices that don’t give bees a pesticide-free buffer zone to forage in. Bee colony collapse is a real concern.
The International Union for Conservation of Nature (IUCN) currently lists 156 species of bees as vulnerable, 20 as endangered, and 11 as critically endangered globally. While these numbers are alarming, there are almost 20,000 different species of bees; in the United States alone, there are around 3,500 species. It is important to keep these big numbers in mind while focusing on the specific species that need protection.
Just like other animal groups, bee species can vary widely. People are most familiar with honey bees and bumblebees. Surprisingly, they are in the minority, as 98% of bee species are naturally solitary, living without a queen or hive. The most common domesticated bee, used for commercial honey and pollination, is the western honeybee (Apis mellifera), which is actually native to Europe, Africa, and western Asia. While its numbers are also declining, the IUCN currently has the species listed as Data Deficient on its Red List of Endangered Species.
All of these species are dramatically dropping in numbers because of a lethal combination of habitat loss, diseases and parasites, pesticides, and the climate crisis. This doesn’t just affect bees, but people, too—after all, it’s bees who play a crucial role in the food supply chain for humans too.
Which bees are at risk of extinction?
Seven of the eight are species of the Hawaiian yellow-faced bee are at risk due to the threat from non-native species of ants that feed on its eggs, as well as from habitat destruction. The rusty patched bumblebee (Bombus affinis) is also listed as an endangered species, and faces the risk of extinction, most likely due to exposure to pesticides and habitat loss from to urbanisation. The population of the rusty patched bumblebee, which is endemic to North America, has decreased to only 0.1 percent of its historic levels. Fortunately, not all bees are endangered, although all face serious population decline due to human activity and climate change.
Why are bees important?
Bees are one of the most efficient and prevalent pollinators. They have a mutualistic symbiotic relationship with flowers and other plants, meaning that both the plant and bee benefit from their interaction: the bees pollinate the plants, spreading the pollen (which they catch on their tiny hairs) from flower to flower, therefore helping the plants reproduce. The bees also eat the pollen, which is a critical component of their diets. The evolution of many flowers has largely been tailored around increasing their attractiveness to bees, favouring flowers that are in the colour spectrum that bees can see (ultraviolet rather than red-hued) and that release a strong, sweet smell when their pollen is ready to take.
However, bees pollinate more than just flowers - many of our favourite fruits and vegetables require the help of bees to pollinate them, from tomatoes, squash, cucumbers, and eggplants to nuts, seeds, and even cotton. It is estimated that about 80 percent of pollination of flowering plants uses the help of pollinators like bees to reproduce. Bees are critical for the stability of our food systems, supporting over 35 percent of global agricultural land - which is why their disappearance is worrying for humans. To the ancient Greeks, bees symbolised immortality. In the 19th century, beekeepers in New England would inform their bees of any major events in human society. Native northern Australians used beeswax when producing rock art. Bees are also important for history experts. Beeswax produces a “chemical fingerprint” that people can assess to identify components in organic residue. Bees are very intelligent, and people have applied knowledge of their mannerisms and social interactions when creating human initiatives.
What would happen if bees went extinct?
The ecological issue of the possible extinction of bees is also a humanitarian issue, as the stability of human populations largely depends on the stability of bee populations. Considering the crucial role of bees’ pollination activities in supporting our agricultural systems, their disappearance would likely result in a food crisis for humanity. Supplies of foods such as apples, berries, avocados, coffee, and onions would fall drastically since they require the help of pollinators to reproduce. With plummeting supplies, the prices of these foods would skyrocket, making them rare and inaccessible to most people. The decimation of these plants would have secondary effects on animals other than humans that also rely on them for food sources, resulting in larger biodiversity loss.
Bees are essential for maintaining the integrity, productivity, and sustainability of many types of ecosystems including natural areas, pasture fields, meadows, agricultural crops, fruits, fruits, backyard vegetables, and flower gardens. Also, non-consumable products like wax, candles, cosmetics, and pharmaceutical products would be affected. Without bees, there will be no more nuts, coffee, cocoa, tomatoes, apples, or almonds, to name a few crops. This could lead to nutritional deficiencies in the human diet, as these products are essential sources of vital nutrients. Medicinal properties of bee venom and other bee products may never be accessible without bees to provide them. In financial terms, the pollination of fruits and vegetables by wild bees has significant economic value.
What should be done?
Just as flowers and bees provide mutually beneficial exchanges, humans - all of whom benefit from bees’ pollinating activities - should help foster the health of bees. Green backyards and gardens can be vital resources for bees. Growing native flowers and leaving weeds to develop can contribute to bee health and numbers by providing food and shelter. Reducing mowing or pruning can help bees by increasing the amount of vegetation available. Increasing rural spaces in urban areas can boost both human and bee well-being.
As per Ankush Dave: “If you love nature and want to protect tiny creatures like bees, leave a wall unplastered where they can build their hives. Plant fruit and flower-bearing trees and leave some dead wood or bamboo or leaf litter for their habitat.” Phasing out dangerous pesticides is also a potion. “Too much use of pesticide is harmful. It is even used for killing grass. This is responsible for bee decline. So, use of pesticides should be gradually phased out and some alternatives should be found, like organic farming. Urban gardens should be created with Mahua, gular, and Arjun trees which attract bees,” he added.
“Earlier, there was fringe or marginal vegetation around arms where bees built hives but now the land is tilled till the edge. I think the marginal vegetation should be reintroduced. Above all, a scientific programme for bee conservation should be run. First, there should be a study and it should be followed by targeted interventions wherever necessary,” said Prof Vankatesh Dutta. The European Food Safety Committee (EFSA) has stated that three major pesticides pose a “high acute risk” to bee species and have been found at dangerous levels within their hives. Governments must ensure that approved pesticides are not harmful to pollinator populations, which in the long run will help increase crop yield and promote sustainable farming. Without adequate environments for bees to build homes and have plentiful food sources, their populations will continue to decline. Preventing deforestation can therefore also prevent bee extinction and, as a side effect, promote higher crop yields.
Promotion of organic products
Organic produce is grown without the use of pesticides and therefore does not have chemicals that can kill bees.
Plant flowers and plants that bees pollinate
If you have a garden, you can plant certain plants that attract bees and other pollinators. Make sure to plant using organic seeds and avoid using fungicides or pesticides.
Buy local honey
Local honey producers support bee populations but need income to support their farms and themselves. Buying locally will help small-scale farmers survive, while also helping the biodiversity of plants and the bee communities in your area. Do not destroy bee hives! While many people are afraid of bees, it is important to understand that they are mostly harmless unless provoked. In fact, not all bees sting - some species do not possess stinging abilities, and male bees do not sting at all. Even female bees that do sting will only sting if directly threatened or attacked. If you don't feel comfortable with bees around, you can contact a local beekeeper association that will relocate the bees to a new home. We celebrate World Bee Day on May 20 to acknowledge the importance of these beautiful and small creatures, whose activities help preserve and perpetuate life on Earth. It is high time we stopped taking them for granted and paid serious attention to checking the decimation of their populations.