During the summer, you may find dead bumblebees lying on your local sidewalk.
There are several reasons for this, some due to the weather and others due to humans.
Bumblebees are sociable, live in colonies maintained by very active worker bees, and have a relatively short lifespan of 4 to 6 weeks. This means that in a relatively short period of time the old bees die and the healthy young workers carry out the dead bees and move them far away from the colony to prevent disease from entering the colony.
Another factor is the weather. June 2026 will be England’s hottest June on record (second warmest in the UK as a whole), with other high temperatures expected this summer.
Heat stress in bees is caused by such extreme heat. Prolonged heat exposure alters development and threatens long-term population stability.
Heatwaves also severely disrupt reproductive, flight, and foraging abilities. Social insects, including bees, rely on cooling behaviors, such as fanning their wings when it gets too hot to cool down the hive, but their effectiveness is limited in extreme heat.
As the weather gets warmer, bees become more foraging and may travel longer distances. Bees can regulate their body temperature by transferring heat around their bodies during flight, but extreme temperatures can affect their health.
don’t kill dandelions
Other factors also play a role in bee death. The use of pesticides and herbicides is common, and these chemicals affect bee health and cause bee mortality. However, these chemicals not only directly affect bees, but they can also kill important plants that bees depend on for food, causing them to starve to death. For example, dandelions are a very important nectar source for bees, but they are also plants that are commonly managed with herbicides. So, don’t weed or pull out the weeds in your garden.
Pesticide use is one of the main historical causes of honeybee decline. Pesticides used to reduce the number of insects that eat crops are, ironically, causing harm to pollinating animal populations.
Although the EU and UK have banned the use of the most harmful neonicotinoids, pesticides are still routinely used, with harmful knock-on effects on pollinators. Insecticides such as organophosphates, synthetic pyrethroids, and phenylpyrazoles not only inhibit honeybees’ ability to migrate, but also cause paralysis and death of these insects.
Habitat loss is also an important issue for bees as land use changes for housing development, intensive agriculture, and human structures such as roads. Without these habitats to support bees, bee populations will suffer.
Climate change is also causing other problems.
Phenological mismatch is when two mutually dependent organisms appear at the wrong time. This is happening because of climate change. An example of this is when a plant that bees depend on is flowering when the bees are not present. Basically, it blooms when there are no bees. They may wake up from hibernation too early and have no nectar to feed on, or conversely, flowers may bloom before the bees appear. Of course, this is a disaster for both flowers and bees.
bees are under threat
Insects are the most diverse and abundant group of animals on Earth, but despite their dominance, they are the most threatened.
We are losing bees at an alarming rate. In Europe, the number of wild bee species considered at risk of extinction has more than doubled, from 77 species in 2014 to at least 172 species (approximately 10% of the species assessed).
But we really need them. They provide tremendous support to our planet as decomposers, exterminators, food for other animals, and generally keeping our systems clean and tidy. Scientists refer to these roles as ecosystem services. But one such service they provide is of direct great importance to us and is disproportionately performed by bees, a group of insects that is the pollination of crops.
Bees are one of the most diverse groups of insects. They support an estimated 75% of the world’s crop pollination and nearly 90% of all flowering plants. The rest is pollinated by other animals, wind, and weather.
If we lose the food security provided by pollinators, we could face a global food crisis.
Is there anything I can do?
Be a thoughtful and informed consumer when it comes to pesticide use. We support locally and sustainably produced food whenever possible and buy from farmers who use nature-friendly practices when possible. This doesn’t necessarily mean choosing organic products, but rather considering how food is produced and the impact that different farming systems have on the environment. As a homeowner, consider non-chemical alternatives first and apply treatments sparingly and responsibly to minimize harm to beneficial insects and other wildlife.
One of the easiest ways to address honey bee habitat loss is to create space for native species. Plant a variety of native flowering species and leave some areas of the lawn unmown. This helps create a safe haven for bees.
In the short term, there is one thing people can do to help struggling bees. If you see a bee struggling on a sidewalk on a hot summer day, giving it sugar water can bring it back to life. A 2:1 ratio of sugar and water works best.
If it is safe to do so, we also recommend moving your bees to flowers or a shady area. However, please do not do this if you have allergies or are easily stung.
