I'd always heard that "ladybugs" (which is what they are called in North America) were supposed to bring one great luck if they landed on you. So you can imagine my shock when I let one crawl on my hand and....the little brat BIT me!!! I quickly shook it off my hand and noticed that it was not the normal red colour of a ladybug. I would do more research. In fact, these orange-coloured insects were a totally different species known as Asian Female Beetle. In U.K. they are called Harlequin Ladybirds but they are one and the same as the Asian Female Beetle. This article seemed to truly do a good explanation of how they were introduced, why....but the sad news is that in North America in Europe they do not have a predator. In Asia, there were predators that kept them from multiplying to millions and millions.
The Harlequin Ladybird (Harmonia axyridis), otherwise known as the Multi-Coloured Ladybird or the Halloween Ladybird, was introduced to North America from Asia in 1988, originally for their aphid-eating abilities. It took several attempts to establish a colony there, so this was not accidental, but a deliberate, planned event by the United States Dept of Agriculture that was to have global implications.
This ladybird is now the most common variety found in the whole of the United States.
At a later date the harlequin was introduced to Holland, primarily for aphid control on crops, and from there it migrated across the English Channel and was first spotted in southern England in 2004.
Since then it has spread both north and east, and is now reckoned to be the biggest ecological threat since the introduction of the grey squirrel, another creature without natural predators, which all but wiped out the red squirrel population.
Bigger than any of the 34 indigenous species native to the the British shores, the Harlequin as it is known in Britain because of its varied colours, not only eats voraciously the same food destined for the British ladybirds, it also eats the smaller native ladybirds and their eggs, as well as the eggs and larvae of many other insects, some beneficial and others less so.
Scientists believe that up to 100 species are now at risk because of this incomer, dubbed the most invasive ladybird in the world.
It is also cannibalistic. It will eat other harlequin ladybirds as well as their own eggs if they are hungry. This happens when the aphid and native ladybird populations die down, as is natural at certain times of the year.
They are also attracted to anything sweet, like fruit, and have been responsible for ruining wine harvests by altering the taste of the grapes with their excretions.
The Harlequin Ladybird (Harmonia axyridis), otherwise known as the Multi-Coloured Ladybird or the Halloween Ladybird, was introduced to North America from Asia in 1988, originally for their aphid-eating abilities. It took several attempts to establish a colony there, so this was not accidental, but a deliberate, planned event by the United States Dept of Agriculture that was to have global implications.
This ladybird is now the most common variety found in the whole of the United States.
At a later date the harlequin was introduced to Holland, primarily for aphid control on crops, and from there it migrated across the English Channel and was first spotted in southern England in 2004.
Since then it has spread both north and east, and is now reckoned to be the biggest ecological threat since the introduction of the grey squirrel, another creature without natural predators, which all but wiped out the red squirrel population.
Bigger than any of the 34 indigenous species native to the the British shores, the Harlequin as it is known in Britain because of its varied colours, not only eats voraciously the same food destined for the British ladybirds, it also eats the smaller native ladybirds and their eggs, as well as the eggs and larvae of many other insects, some beneficial and others less so.
Scientists believe that up to 100 species are now at risk because of this incomer, dubbed the most invasive ladybird in the world.
It is also cannibalistic. It will eat other harlequin ladybirds as well as their own eggs if they are hungry. This happens when the aphid and native ladybird populations die down, as is natural at certain times of the year.
They are also attracted to anything sweet, like fruit, and have been responsible for ruining wine harvests by altering the taste of the grapes with their excretions.
Breeding Habits
The harlequin has settled into its new environment exceptionally well.They breed 5 times a year, unlike the native ladybirds which only breed twice a year, and this has massively contributed to their growth and spread.
Unlike British ladybirds, they do not need a cold winter to mature enough to breed.
Unlike British ladybirds, they do not need a cold winter to mature enough to breed.
They Bite
Every autumn they seek out shelter to hibernate, and they are the only variety of ladybird to invade the inside of peoples' houses, where they cause havoc by staining carpets and furniture with their 'reflex bleeding' which is a normal response ladybirds have to a threatened or perceived attack, which smells extremely unpleasant and is difficult to remove.
They also bite, which can be problematic for people who are allergic to their bites.
They have a habit of forming together in their thousands if not millions, especially in a situation where they are warm and cosy.
There are reports of whole streets virtually carpeted with them!
They also bite, which can be problematic for people who are allergic to their bites.
They have a habit of forming together in their thousands if not millions, especially in a situation where they are warm and cosy.
There are reports of whole streets virtually carpeted with them!
Ladybirds ar a beach in Germany
Predators
Their greatest problem in the UK and Europe, they have no known predators. Birds won't eat them because of the foul-smelling secretions they release. Other insects give them a wide berth.
They are free to breed and continue breeding, and being top of their food chain, they are rapidly outnumbering the local species.
They are antisocial as we have seen; humans do not want them in their houses.
They are free to breed and continue breeding, and being top of their food chain, they are rapidly outnumbering the local species.
They are antisocial as we have seen; humans do not want them in their houses.
some of the different colours of the harlequin ladybird
Asia
Over in Asia, where they originally came from, there was no problem with them as obviously they have insects or birds which have been programmed by Mother Nature to keep their numbers under control. Europe and North America obviously lack the same ecological species, but of course introducing something which eats the harlequin would cause problems elsewhere in the food chain, as the natural ecological balance gets upset.
Wow, very interesting! Thanks!
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