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The Causes and Consequences When the Bee Population Declines

This article is about what are the causes and consequences of the decline in the bee population.



Bees are essential pollinator and a bio-indicator of a healthy environment. Studies show there are around 20,000 known species of bees in the world. Out of which more than 4,000 species are found in the USA. However, a recent survey indicates there has been a drastic decline in the bee's population over the last two decades. From April 2018 to April 2019, a decrease of 40.7 % of the managed bee's population is reported from the USA. In addition to this, Portugal, Northern Ireland, Italy, and England said more than 25 % decrease in the bee population in the winters of 2017 - 2018.

Factors leading to the decline in the Bee Population:

The decrease in the bee population in recent years is due to several factors, and these are as follows:

Habitat Loss:

Habitat Loss is one of the significant factors which have led to the decline of the bee population. Habitat loss of the bees is caused by land-use changes, intensive farming, and deforestation.

Bees need large spaces along with abundant wildflowers to feed on as well as a clean and undisturbed environment to thrive. However, due to land-use change, many forested areas were converted to buildup areas for developmental activities. Thus, wiping out the wildflowers which the bees feed and the entire bee colony.

Similarly, the conversion of forested areas to intensive farms has also affected the bee population. Clearing forest areas has led to the loss of many wildflowers, which is one of the primary sources of food for the bees. Hence, with a shortage of food, the bees, and the Queen will not survive as a result; the entire bee colony will collapse.


Climate change:

Climate change has become one of the reasons for the decline in the bee population in recent years. The difference in temperature, erratic precipitation, and extreme weather events has changed the behavioural pattern of an individual bee and ultimately, their communities. Further, such changes have altered a shift in the timing of flowering plants which the bees depend on for food. Therefore, fewer flowers during spring will indicate less food for the bees, which in turn will affect the Queen bee and her offspring, resulting in a decline in the bee population.


Invasive species:

Invasive species are drastically reducing the bee's population. Studies show that the spread of Lantana Camara (invasive plant species) in India has curbed the growth of the native wildflowers which the bees collect nectar to feed their colonies. Similarly, the invasion of the Asian hornet in certain areas has affected the bee population, as these hornets kill the honey bees and wipe out the entire colony leading to a bee massacre.


Diseases and Pests:

Bee colonies are very vulnerable when exposed to pests. When this virus infects bees, they die within a week or two, and the entire province crumbles. The parasitic mites cling on to the bees and transmit the disease. Being infected by the transmitted disease, the bees become weak to fly and are unable to reproduce, eventually resulting in their death.

Research shows that; the emergence of chronic bee paralysis has reduced the bee population significantly. Chronic bee paralysis is a disease which is caused by a virus called chronic bee paralysis virus. When this virus infects bees, they die within a week or two, and the entire colony crumbles



Bees are important keystone species in the ecosystem. They play a significant role as pollinators and bio-indicators of a healthy environment. However, the decline of the bee population over time can affect the entire ecosystem. Some of the consequences of the declining bee population are as follows:

1. Bees are keystone species, their role as pollinators helps a variety of flowers to grow, and this eventually becomes a new habitat for other insects and birds. Studies show that various animals depend on the bees, as their source of food, such as fruits, berries, and seed relies on bee's pollination. Hence, if the bee population continues to decline, it will affect other organisms, flowers, and trees, which depend on the bee resulting in the collapse of the entire ecosystem.

2. A mutual relationship is seen between the bee's population and food crop production. Research study shows that the bee's population is responsible for pollinating 35 % of the global food crops. The decline of the bee's population over the years has not only affected the production of agricultural food crops, but it has also affected the livelihood of the people working in the farming sector.


3. Besides, the vital role played by bees; they are also an essential contributor to the economy of a country. Several studies show that global food crop production pollinated by bees is valued at 577 billion dollars. In the USA alone, these pollinators contribute around 24 million dollars to the agricultural industry.

The demand for honey in the international market is growing immensely, and this has contributed to an increase in the nation's gross domestic product (GDP).


Conclusion and Recommendations:

However, the decline of the bee population due to habitat loss and climate change has affected the global market and supply of honey.

Hence, to protect these endangered species, several steps should be taken, and some of these are as follows:

  • Ban bee-harming pesticides.
  • Protect pollinator health by preserving wild habitat.
  • Restore ecological agriculture.
  • Encourage the practice of Apiculture.
  • Increase diversity and abundance of flower resources within the agriculture landscape.
  • Increase funding for research and development on Apiculture.
  • Increase funding for ecological farming practices.

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