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Gardeners' World prog about invasive non-native species


Did you see last weeks episode of Gardeners’ World when Prof Helen Roy from the Centre for Ecology & Hydrology spoke about the invasive non-native species that threaten our native ones such as the Harlequin Ladybird & the Asian Hornet.
I was unaware of this & her words really perturbed me. Considering this is not a new phenomenon information it’s not that widely known (or else I’ve been in the dark too long). So I did a bit of surfing to find out more.

It’s too late to eradicate the Harlequin ladybird as since it was first spotted in Essex in 2004 in just 4 yrs it had spread nationwide & as far north as Orkney. Scientists had warned of the devastating consequences of its spread saying that up to one thousand insect species are at risk from the predator.
Credited with being the most invasive ladybird on Earth and the fastest spreading in Europe the destructive beetle feeds mainly on aphids and will also devour other ladybird eggs, larvae and pupae, butterfly and moth eggs and caterpillars.

The unfortunate native ladybird already has much to contend with like the parasitic wasp Dinocampus coccinellae that not only lays an egg inside the beetle it also releases a virus that controls its’ brain, keeping it alive so that it twitches unnervingly providing protection for the growing grub until it emerges .

You can join the Ladybird Challenge which has been set up to record sightings of this wasp, it also shows how to identify both victim & prey.

The next 3 photos are varieties of Harlequins. All photos are images taken from the Ladybird site or internet for accuracy.

This is a very good ID chart for ladybird varieties

The following stages are particularly gruesome.

When the grub is in its 4th instar (stage), it pushes out the back end of the ladybird and spins a silk cocoon between the legs of the ladybird, fixing it down to the surface it is on. The ladybird is now able to twitch and protect the wasp from being eaten, but it cannot get away.

What does a herbivore eat? Plants. What does a carnivore eat? Anything it can get.

The larval stage has a voracious appetite. Apart from eating aphids it also eats other insects including other ladybird larvae and also lacewing and hoverfly larvae feeding in the aphid colonies & it is known to be cannibalistic.

This is a Harlequin ladybird larva attacking a Harlequin ladybird pupa.

The wasp develops inside the cocoon and transforms into an adult wasp. The wasp chews its way out of the end of the cocoon before flying off in search of a new ladybird.

The Ladybird remains glued to the cocoon and is generally unable to ever get away.

However, a study carried out in 2015 discovered that despite being disembowelled & subjected to this horrific experience almost 25% survive. Some even live through​ multiple parasitic invasions. These resilient beetles are able to bolster their immune systems enough to permanently kick the brain controlling virus out of their system.

How weird is that!

Are you still reading ……..?

Now the Asian hornet is another matter, so far eradication has been successful but please do be vigilant. If you think you see one try & get a pic & note the direction it’s going – this will help authorities to locate the nest & use the app to make a report.
The is app called appropriately The Asian Hornet Watch

or send email with details & picture if poss to:

This hornet stings. Do not disturb an active nest.
Seek advice using the details above

This from the Centre for Ecology and Hydrology

Asian Hornet Watch is an app designed to record and help the early detection of Asian Hornet in the UK following the first confirmed record in September 2016. Asian Hornet is a non-native species within the UK and could have a serious impact on our insects including honeybees so early detection is important. There are a number of native insects in the UK that look very similar to the Asian Hornet, and are common and widespread. Asian Hornet Watch provides an identification guide to help check which species you have seen and an opportunity to record your sightings. Insect identification can be difficult and so please do include a photograph with your record to help us confirm the identity of the species you have seen.This is what it looks like….

Asian hornet (Vespa velutina)
Queen up to 30mm long, worker up to 25mm long
Legs yellow at the ends
Dark brown / black abdomen with a yellow/orange band
on 4th segment
Head dark from above, orange from front
Dark coloured antennae
Entirely black velvety thorax
Never active at night

It poses a serious threat to honeybees in particular whereby it hovers like a mini helecopter over the entrance to hives & snatches the bees in mid-air as they try to enter or leave the hive.
It also feeds on beetles, moths, wasps, larger bees.

The first sighting in the UK was in Tetbury, Gloucester Sept 2014, the nest was found & eradicated, likewise in Somerset. Just two days ago, the hornet was found on Guernsey.The discovery follows similar sightings of Asian Hornets in Jersey, Alderney, and Sark in recent months.

Thanks if you managed to read this far, I think this is the most I’ve ever written in a blog.

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Have added to Favourites rather than giving it a Like - its horrible! thank you for the warning.

30 Jul, 2017


Also added to my favs so I can get to it quickly for recognition, I don't think I saw all of that programme as I always skyplus and watch it later,must put it back on, did see the bit about the creature living inside the prey. sincerely hope I don't see that Hornet, might sound a tad silly but I was ecstatic to see a native Ladybird on a pondplant yesterday, family wondered what I was excited about, they just don't get it, one even got trapped in my clothing today after a stint in the garden, thats three this year, however and this I do not understand although must admit quite relieved in some ways, I haven't seen a single ant this year and although its apple ripening time and with all the wind I'm forever picking them up before the dogs get them, we haven't seen any wasps for the last two years...Its not good is it.....
Very interesting and imformative blog,for taking the time to put it all together, thanks Greenfinger ...

30 Jul, 2017


It is a horrible subject & the more I researched the more I realised these few few species I've written about are just the tip of the iceberg.
There's an ant on the list too, Lasius neglectus forms supercolonies.
If you run a search for non native invasive species you will be shocked at the long list on DEFRA's site. It covers flora, fauna & amphibians.
I saw one very small yellow with black dots ladybird today, if I see a red one I shall look at it carefully now.

31 Jul, 2017


Didn't see the programme. Wish I had. The world is a very small place now and we have lots of invasive species as a result. Saw a suspect ladybird last year and for the first time ever, killed a ladybird. Really went against the grain!
We have had hornets here and they are BIG! have not seen the Asian Hornet and don't want to. have seen a what they can do. Our bees are in enough trouble, as it is.

Lincslass: had ants in our kitchen this Summer. They marched out from behind the oil boiler and it was obvious they were ready to leave the nest. Washed the whole place down with white vinegar before buying special Ant Powder. So far, so good!

The parasitic wasp is the stuff of nightmares. Wonder if the idea of the Alien films was based loosely on them?

31 Jul, 2017


Eirlys I always think the same way, I'm a wuss and an ordinary hornet sets me running indoors, dread to think of one of the others visiting, do you know I think it would put me off my garden completely....I have to clean my pond filter regularly, normally at this time of the year it would be a case of moving an ants nest before attempting to kneel down near my pond, they have always nested under the gravel bed and down the side of the pond, as I said we haven't seen any yet, even started clearing between the pavers on the driveway, usually that disturbs them in lots of places but no signs there either.....Now if only something would come along and destroy the Vine Weevil, Lily Beetle and Laburnam Beetle then I might be thankful.....

31 Jul, 2017


Eirlys, you can see any of the progs you missed on Watch again. They are telling us not to kill the ladybirds .....

‘We tell people to leave them alone rather than kill them because we don’t want people squidging native ladybirds,’ Jamie Robins, conservation officer for Buglife.

Although if it has those 2 big white 'eyes' it will be a Harlequin.See this pic...

The Asian Hornet is smaller than our native one, we are advised not to try to kill it but notify via the app or send email

Don't run.They can fly faster than you can run and are intrigued by moving targets and consider running a provocation. Crouch low to the ground, stop moving and try to cover your head.

31 Jul, 2017


I missed the programme as well but neither of these two non-native species are new to me. I'm pretty sure I've seen the Harlequin Ladybird but not the Asian Hornet - thank goodness! (I haven't even seen our native Hornet!)

31 Jul, 2017


And let's hope we never do, David.

31 Jul, 2017


Fascinating blog Greenfinger. I did watch the programme which was just another depressing example of how we can import foreign species into this country. We don't seem to have any checks like they do in Australia (from watching the programme about border control) where them ban any living plant, dead wood or dodgy food stuffs!
I have seen them fumigate containers in case there are non-native insect lurking, we don't do that I am sure, but then we can't control illegal immigrants so what chance have we got in controlling something small like an insect?
As for those that get here themselves, not much we can do about that, but the Asian Hornet is spreading on it's own accord and is in France, so only a skip away from here, a tail wind or handy lorry and we will have more than the odd one.

1 Aug, 2017


The thing that I really don't understand is how these things are not new, 1st hornet 2 years ago, 1st ladybug 13yrs ago & Defra has a long list of others .... they say they need the publics support to notify them yet why isn't it more widely known? OK so Joe Public may not care but what about all the gardening groups, GC's, plantsmen, environmentalists etc.
They say most comes in via plants & the compost they're in.
I don't know what import checks are done here but you're right about Australia.

2 Aug, 2017


Thanks for writing this blog. It is very interesting. I did see the program and think it's worrying how easily these things can get here.

I haven't seen a Ladybird for a long time. I saw one small one a few years ago but that was the only one for many years. I haven't even seen the Harlequin ones.

2 Aug, 2017


Hywel, I've seen one tiny yellow ladybird, only a few butterflies, lots of bumble bees, not so many honeybees but we took out the big fuchsia that used to be smothered in them & I've seen ants but only a handful of aphids.

Whether this is due to invasive species, disease, the weather, chemicals or something else is difficult to know.
We can only make our little bit of the environment as friendly for them as we can.

2 Aug, 2017


Yes I agree :)

2 Aug, 2017


Great blog

also just discovered in the UK;

Agapanthus gall midge arrived 2014

Rosemary beetle that also like lavender to feed on

Spanish slug

New Zealand flat worm nothing much mentioned about this anymore ?

I bet lots more to the list ....


11 Aug, 2017


Andy, New Zealand & Australian flatworm are on the list.
I've posted the full list on the next post along with the link to the site.

New Zealand flatworm and Australian flatworm: they have been established in Britain for more than 40 years and are causing concern as they feed exclusively on earthworms. In some parts of Britain and Ireland they have reduced the earthworm population to very low levels, with consequent adverse effects on soil quality and the native animals that also prey on earthworms. The New Zealand flatworm is mainly found in Scotland, Northern Ireland and the north of England while Australian flatworm is most frequent in south west England
ACTION: Gardeners who have either species of flatworms should avoid moving soil, compost or rooted plants from their gardens to other areas that are currently free of flatworms. Suspected new plant pests or diseases should be reported to the Plant Health and Seeds Inspectorate or send samples to FERA Room 10G A01, Sand Hutton, York, YO41 1LZ.

12 Aug, 2017

On this site each species can be clicked on & you will see a full ID sheet.

List of Invasive Non-native Species

African Clawed-toad (Xenopus laevis)
Alpine Newt (Mesotriton alpestris)
American Mink (Mustela vison)
American Lobster (Homarus americanus)
American Skunk-cabbage (Lysichiton americanus)
Asian Hornet (Vespa velutina)
Asian Shore Crab (Hemigrapsus sanguineus)
Australian Flatworm (Australoplana sanguinea)
Bar-headed Goose (Anser indicus)
Black Swan (Cygnus atratus)
Brush Clawed Crab (Hemigrapsus takanoi)
Bull Frog (Lithobates catesbeianus)
Canada Goose (Branta canadensis)
Canadian Goldenrod (Solidago canadensis)
Canadian Waterweed (Elodea canadensis)
Carolina Watershield (Cabomba caroliniana)
Carpet Sea Squirt (Didemnum vexillum)
Chinese Mitten Crab (Eriocheir sinensis)
Chinese Water Deer (Hydropotes inermis)
Coatimundi (Nasua nasua)
Cotoneaster (Cotoneaster species)
Curly Waterweed (Lagarosiphon major)
Edible Dormouse (Glis glis)
Egyptian Goose (Alopochen aegyptiacus)
Emperor Goose (Chen canagicus)
Eurasian Eagle Owl (Bubo bubo)
Evergreen Oak (Quercus ilex)
False Acacia (Robinia pseudoacacia)
Floating Pennywort (Hydrocotyle ranunculoides)
Garlics (Allium species)
Giant Hogweed (Heracleum mantegazzianum)
Giant Rhubarbs (Gunnera species)
Giant Salvinia (Salvinia molesta)
Himalayan Balsam (Impatiens glandulifera)
Hottentot Fig (Carpobrotus edulis)
Indian House Crow (Corvus splendens)
Japanese Knotweed (Fallopia japonica)
Japanese Rose (Rosa rugosa)
Killer Shrimp (Dikerogammarus villosus)
Kontikia Flatworms (Kontikia ventrolineata and andersoni)
Leathery Sea Squirt (Styela clava)
Marsh Frog (Pelophylax ridibundus)
Midwife Toad (Alytes obstetricans)
Monk Parakeet (Myiopsitta monachus)
Montbretia (Crocosmia x crocosmiifolia)
Muntjac Deer (Muntiacus reevesi)
New Zealand Flatworm (Arthurdendyus triangulates)
New Zealand Pigmyweed (Crassula helmsii)
Nuttall's Waterweed (Elodea nuttallii)
Orange Sheath Tunicate (Botrylloides violaceus)
Parrot's Feather (Myriophyllum aquaticum)
Red-eared Terrapin (Trachemys scripta elegans)
Rhododendron (Rhododendron ponticum)
Rose-ringed Parakeet (Psittacula krameri)
Ruddy Duck (Oxyura jamaicensis)
Russian-vine (Fallopia baldschuanica)
Sacred Ibis (Threskiornis aethiopicus)
Siberian Chipmunk (Tamias sibiricus)
Signal Crayfish (Pacifastacus leniusculus)
Sika Deer (Cervus nippon)
Slipper Limpet (Crepidula fornicata)
Turkey Oak (Quercus cerris)
Wakame (Undaria pinnatifida)
Water Fern (Azolla filiculoides)
Water Lettuce (Pistia stratiotes)
Water Primrose (Ludwigia grandiflora)
Western Green Lizard (Lacerta bilineata)
Wireweed (Sargassum muticum)
Wood Duck (Aix sponsa)
Zebra Mussel (Dreissena polymorpha)

12 Aug, 2017


Thanks for this

I wouldn't mind a black swan wandering around the garden lol


12 Aug, 2017


Andy, apparently they are known to be aggressive so I think I'd prefer a Wood Duck.

12 Aug, 2017


I wonder where the sacred ibis are - now seeing one of those that would be a shock!

12 Aug, 2017


Stera, I had to go to the site to see the info sheet on that, it says: free-flying birds in zoos and parks have established several feral breeding populations. The largest feral colonies currently exist on the French Atlantic coast. The sacred ibis is an opportunistic feeder and will predate on eggs and young of other birds. In France, predation of tern colonies has been observed, as well as the nests of mallards and a variety of other waterbirds.Their large size represents a bird-aircraft strike hazard.

This weeks GW hi-lighted the Hottentot fig plant.

13 Aug, 2017


The stuff of nightmares!! so much to worry about!

18 Sep, 2017


Quite so, DD, you can understand why some think ignorance is bliss.

19 Sep, 2017


Just re-read all the above. The mention of Russian Vine made me feel guilty. Because I liked its appearance, I "secretly" planted some in the hedge many years ago and my husband couldn't believe his eyes when it appeared. I learnt some new,(not too bad), swear words. Since then we have waged war on the Vine. It IS invasive!!

26 Sep, 2017


Eirlys, you & me both! I did the same once to cover an old shed which it did, I liked the frothy white flowers effect but it didn't stop at the shed, lol

We've also got Black Bryony, which isn't on the list but I think is bad news. Apart from the weight of the twining stems breaking down other plants, it is highly poisonous. It's attractive with shiny heart-shaped leaves & has strings of bright red berries like beads. Digging it out is almost impossible, it has an enormous deep parsnip like tuber.

26 Sep, 2017



bad news !!!!Just found this out today from my Bee association


"It has now been confirmed that the following the discovery on 18 September 2017 an Asian Hornet has been positivelyt identified in North Devon. Beekeepers in that area will be contacted by Bee Inspectors in order to carry out apiary inspections and to hand out killing traps"

28 Sep, 2017



Thank goodness it was spotted & lets hope it is just a rogue wanderer & can be dealt with.
Don't these things go dormant for winter?

28 Sep, 2017



They produce queens hornets now that will go off individually to hibernate till next spring ... so the race is on to find them , they were also found in Guernsey as well over the summer for the first time so wont be long before they are here permanent !! not good is it !!!


29 Sep, 2017


No, def not good! Let's hope all beekeepers are particularly vigilant as well as the rest of us.

30 Sep, 2017

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