New clues to decline of bees and other pollinators
The title of this article could read as, this is ‘the’ possible reason bees and other pollinators are in decline! (Is due to hoverflies) Be under no illusion folks, this is but another layer suggested layer to the story and it is most likely incorrect!
If you take honeybees as an example, then you ask yourself, how have honeybees survived over 90 million years, (far longer than humans), they will have faced many diseases in that time and survived?
Bees and other pollinators are not in decline, there are several threats though, all with a single root cause.
When you use honeybees as the example (given they are so visible through beekeeping).
The reasons include:
- Declining foraging
- Movement of goods introducing diseases
- Movement of goods about to introduce small hive beetle (Yet to reach the UK in numbers, but crossing Europe)
- Import of non-native honeybees, introducing non-native threats such as varroa mites (Massive threat to bees)
- Insecticides, not just neonicotinoids
- Large swathes of mono-crops, bees need a varied forage diet, just like we need a varied diet to stay healthy.
- Honeybee management practices, such as moving bees to pollinate crops
The root cause?
- Homo Sapiens
We interfere, a lot.
Please do not misunderstand, there is no direct intent from us, which is what makes the situation more deadly, we see nothing wrong, yet, bees and other pollinators are under threat from our way of life.
This is somewhat like the industrial age, whereby humans advanced so quickly with little regard for pollutants and other impacts. Then our health was becoming directly affected, affirmative action was taken, clean air act anyone?
When something directly and obviously affects us as a species, we fix it, until then we simply accept.
The threat to bees and other pollinators is currently subtle, there is no obvious direct impact upon humans, yet!
Honeybee numbers are being kept artificially high due to the efforts of beekeepers.
With regards to other pollinators (Read: Bugs) all I ask you is this, when was the last time you had to clean your windscreen?
So fewer bugs, so what, that is a good thing, no? Well in terms of a clean windscreen, great, in terms of our survival as a species, less so, bugs form part of the ecosystem, a system slowly but surely being eroded.
Appreciate the above will fall mainly on deaf ears, it is human nature to make continuous progress, unfortunately, there is always a cost to everything else around us.
We will never fix the problem until it directly threatens us as a species! Until then it would be fantastic if we simply attempted to balance the books a little.
Bee diseases have been detected in hoverflies for the first time.
The brightly-coloured flies may be picking up bee viruses as they forage at the same flowers.
And scientists think hoverflies could then be spreading the deadly infections long distances when they migrate.
Bees and other pollinators are vital to most of the world’s food crops but have been in decline in recent decades due to the destruction of wild habitats, disease and pesticide use.
It’s not clear if hoverflies are harmed by the viruses or are simply carriers, but, either way, they could be moving them around the countryside and over long distances, say UK researchers.
“The hoverfly species that we detected the viruses in are known to migrate across Europe,” said Emily Bailes of Royal Holloway University of London.
“They’re moving a lot further than say a honey bee would and so you could be moving different types of the viruses into new places where the bees haven’t been exposed to those before.”
Infectious diseases have been identified as a key driver of bee population declines.
Scientists have a clear picture of parasites and viruses that can damage honey bees, but much less is known about what is happening in hoverflies and other pollinators.
Hoverflies themselves are important pollinators of crops and wild flowers.
They can be very mobile, and some migrate long distances every year.
The research, carried out in collaboration with Oxford University, looked at four types of hoverflies collected at woodland in Oxfordshire.
The samples were analysed in the lab for the presence of viruses. Three common bee diseases were found in two types of hoverflies that feed at the same flowers as bees. These cause symptoms like deformed wings which lead to rapid death or the bee being expelled from the hive.
“We don’t really know what they’re doing there yet, but because hoverflies are visiting the same flowers as bees, they could be spreading the virus around in quite a different way to the way that the bees are,” said Dr Bailes.
Karl Wotton of the University of Exeter, who is not connected with the study, said there are about a dozen migratory hoverflies that move seasonally through Europe and in many other parts of the world.
“The numbers entering and leaving the UK each year are huge, in the billions, and all the while they provide ecosystem services including pollination and, for some species, biological control of crop pests,” he said.
They are almost certainly transferring pollen to create pollination networks that link across national borders, raising the question of whether they are doing the same with bee viruses.
“Perhaps,,” he added, “but it remains to be seen how the virus may affect the ability of hoverflies to undergo a strenuous long-distance migration or how long the virus may persist in their bodies given that no viral replication was detected.”
The research is published in the Royal Society journal Biology Letters.
Curated from: BBC