Environment America Has Discovered the Cause Behind Massive Decline in Bumblebee Populations

By: Stephanie Bontorin | Published: May 03, 2024

A major breakthrough has just been made. Answers as to why bumblebee populations have been declining in the past two decades might now be solved. 

In the past 20 years, more than 90% of bumblebees worldwide have died out, causing a massive ripple effect throughout agriculture and nature.

Environment America Onto the Reason

There are a number of factors that have contributed to the endemic decline of bees around the globe.

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Environment America, a network made up of more than 30 state environmental protection groups, have pinpointed problems with pesticides, urban development, and crushing changes due to climate change.

The Importance of Bees on the Environment

Although bees and bugs during summer might seem like a hindrance, bees are integral to the ecology of Earth.

A stripped bee sits on a yellow flower next to a yellow background

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Without bees, no plants could be pollinated and, therefore, no fruit, vegetables, trees, or bushes could grow.

Recent Study With Big Impacts

A new story titled Frontiers in Bee Science has uncovered the true extent that rising heat caused by global warming has had on the helpful little creatures.

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The scientists who took part in the study say that the rising temperatures around the globe are the reason for the massive decline in bee numbers.

Researchers at the University of Guelph Making a Difference

The study took place at the University of Guelph in Ontario, Canada. Lead researcher, Peter Kevan, says that “The decline in populations and ranges of several species of bumblebees may be explained by issues og overheating of the nests and the brood.”

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In other words, bee larvae and adolescents cannot survive the elevated heat in many places during the summer while they are in their infancy stages.

Increased Heat Causing Damage in Bug Populations

The issue with rising heat causes the bumblebee brood to lose a large amount of larvae in the spring and summer.

A group of bees hang onto the side of a grey and brown surface

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In most places in North America, summers can rise well above 90 degrees Fahrenheit, which is proven to be lethal to bees.


Similar Trends Across the Globe

Although the researchers began their investigation in bee populations around North America, they found startling similarities across the world.

A bumblebee sitting on a purple flower

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In almost all continents, Kevan and his team found that bees were dying during the larvae and infancy stages due to rising temperatures.


Troubling Factors Identified

To get to the bottom of the issue, the team looked at 180 years of studies and literature recorded on the friendly bugs.

A close-up view of a bee stuck to a glob of honey

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What they discovered was that bees can survive in temperatures up to 96.8 Farenheight. However, the ideal temperature is just below 90 at 89.6 F.


Bees Can’t Thermoregulate With the Rising Temps

Although bees do have the ability to regulate their body temperature as heat rises, such as in the way that humans sweat and dogs pant, they cannot be helped above a certain level.

A group of bees fly towards their hive

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When a colony or nest becomes too hot, the larvae and younger bees cannot thrive. As well, bees of full maturity have also been known to succumb to heat stroke inside of a hive.


Bumblebees Rely on Collective Survival

Just like other bugs that live in nests, bees rely on the collective health of their hive to survive.

A bee keeper takes a plank full of bees out of a wooden box hive

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They exist with an extremely delicate ecosystem. When one aspect of their environment changes, they might not be able to adapt and overcome it. This is the main reason why full hives are dying out.


Similar Studies on Honeybees

During their research, Kevan and his team discovered a similar temperature threshold on honeybees.

A few bees fly into a small opening in their hive

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Another essential species to the survival of many crops, the honeybee cannot survive in temperatures that regularly hit above 35 degrees celsius.


More Research Still Needed

With many aspects of the fight to curb climate change, more research is still needed on this topic.

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Kevan plans to inspire future scientists to study similar issues around the globe to come to a concrete resolution.