Bees Under Attack
Can Science Solve the Problem?
Beekeepers around
the world are reporting
unusual losses of
honeybee colonies.
During the winter of
2012-2013 colony losses
of more than 10%
were recorded in
11 EU Member States.
Losses of almost 30%
were reported in
the UK and Sweden.
In Belgium, the figure
was 34%.
Bees play a vital role in
the food chain as pollinators
of plants and crops.
Honeybees also produce
food such as honey
and pollen.
What is causing
the problem?
There is no
single cause of
this global trend,
although single stressors
can be identified as
culpable in certain
cases.
There is growing
evidence to suggest
that in many instances a
number of stressors are
responsible, acting
separately or in
combination.
Biological
stressors
01
What are the main biological stressors?
The main parasite is the Varroa mite.
Also known as Varroa destructor, it’s an
invasive species from Asia that is now
found worldwide.
The varroa mite feeds on bees’ circulatory
fluid and spreads viruses and bacteria.
What are the main biological stressors?
Diseases such as Foulbrood and
Nosema can devastate bee hives.
What are the main biological stressors?
The Asian hornet (Vespa velutina) is a
fierce predator of honeybee colonies
and other pollinators.
It is a growing threat to bees in Europe.
What are the main biological stressors?
The small hive beetle
(Aethina tumida) and
Tropilaelaps mites also
attack bee colonies
around the world.
The small hive
beetle was first detected
in Europe in 2014.
Chemical and
contaminant
stressors
02
How do chemicals reach bees?
Gardening
(mainly through
spraying).
How do chemicals reach bees?
Beekeeping (through practices
such as the use of veterinary
products on hives).
Environmental
stressors
03
How do environmental stressors affect bees?
Climate change is causing
changes in the growth
cycle of plants through,
for example, drought or
shifts in seasonal rainfall.
These changes in turn
affect the availability
of the nectar and
pollen on which
bees depend
for food.
How do environmental stressors affect bees?
Modern agricultural practices
have led to habitat change and
loss, reducing sources of food
and – for wild bees –
nesting areas.
How do environmental stressors affect bees?
Insufficient or poor-quality
diets can weaken bees’ immune
systems, making them more
vulnerable to other stressors
such as infectious agents.
There is already
evidence that multiple
stressors acting in combination
can be more damaging to
bees than when
acting alone.
