Category Archives: London Invertebrates

After the Rain at Barnwood

Dear Readers, it’s always interesting to see what has and hasn’t thrived during the drought of the past few months. At the Barnwood Community Orchard, some of the trees and fruiting shrubs are still doing very nicely, even the recently planted ones (largely due, I suspect, to the care and attention given to them by the volunteers at the site. On the other hand some plants, such as the hazel to the left of the photo, are covered in crisp brown leaves and look very sorry for themselves. I wouldn’t give up hope just yet, though – native shrubs such as this can be very resilient, and it’s more  than possible that it will resurrect itself after the recent rains.

Many of the other plants are looking very healthy. This guelder rose (Viburnum opulus) is full of berries. What good value this plant is, with its white flowers in spring, its red fruit in late summer and its fine golden colour in the autumn. It’s also one of the national symbols of Ukraine, and so it couldn’t be more appropriate.

I love the way that small fruit trees look when they have a few pears or apples on them – they often look almost overwhelmed by what they’ve produced. This little apple is called ‘Ellison’s Orange’, and is apparently a cross between Cox’s Orange Pippin and a variety called Cellini. It’s said to develop an aniseed flavour in storage (unlikely to be a problem this year as I imagine these apples will get munched up very quickly), and to be more disease-resistant, and juicier, than Cox’s. However, it is said to be prone to apple canker (a fungal disease of apple trees that attacks the bark) and therefore requires good drainage. The variety was first seen in 1905, and is believed to have been developed by C.C. Ellison, a Lincolnshire priest who clearly had a fondness for apples.

Ellison’s Orange

Now, as usual I was keeping my eyes open for invertebrates, and I found a very fine spider on some dried-up teasel. It seemed to be feeding on a shieldbug nymph, and at first I thought it was something exotic – look at that lovely lacy pattern on the abdomen.

But no, this our old friend the Noble Spider (Steatoda nobilis) – I normally have a couple of these living in my sash windows in the kitchen. The good folk at the UK Spider Identification Group on Facebook, along with many other people, have been trying to rehabilitate this rather fine spider by changing its common name from ‘Noble False Widow Spider’, which was rather playing into the sensationalist headlines of the tabloid press. Schools have been shut down because of this spider, people have accidentally burnt down their houses by trying to get rid of them with flame throwers and they have been blamed for people losing their limbs.

It’s true that they can bite, but only if provoked or trapped next to skin, and in most cases the result is no worse than a wasp sting. There have been cases of infections after ‘spider bites’, but this would be the case with any puncture wound, and in none of the cases has the initial cause been proven. In short, if you leave these guys alone (the male is more prone to bite, but only because he wanders further in search of a mate, and is therefore more likely to come into contact with people), and just admire them from a safe distance everybody will be ok. And just think of all the midges and mosquitoes and houseflies that they consume! Spiders are some of my favourite house guests, and I don’t even need to change the bed.


And finally, here is a Barnwood-related puzzle. A moth trap has been run in Barnwood for several months, but when Leo, custodian of all things Barnwood-related, opened the trap to inspect it a few days ago, he found that all  the Jersey Tiger moths had been beheaded and partially eaten. What could be causing this crime? We did wonder if the culprit was the mosquito who was found alongside the ‘body’, but only briefly.

Jersey Tiger with completely innocent mosquito

The murderer is likely to be a wasp – they are voracious hunters, and I believe that they can learn about food sources, and how to exploit them. They may even communicate with one another to reveal where food is. Leo is currently considering how to manage this new problem – he notes down the moths that he finds and releases them safely, but has never had dead moths before. It will be interesting to see what happens next.


A Very Fine Bug

Dear Readers, one of the advantages of being a lover of invertebrates is that, during this hot weather, all manner of creatures have flown into the house. The house flies and green bottles are something of a nuisance, but then there are animals like this tiny bug with its very impressive red and black patterning. I rather think that it looks like an impressive African mask.

This is a Cinnamon bug, or Black and Red Squash Bug (Corizus hyoscyami), also known as a ‘scentless plant bug’ to distinguish it from the more commonly-seen stink or shield bugs. It was a very relaxed creature, allowing me to gently prod it into a glass once I’d taken its portrait, and ambling onto a plant once I’d taken it into the garden. None of that manic buzzing that many insects indulge in when trapped! Historically this insect was found in coastal areas but (and here I feel a bit like a stuck record) it is moving north as our climate changes. It also favours dry environments, which might also help to explain the increase in its range.

The Cinnamon bug belongs to the Rhopalid family, all of which are plant-feeders, though none are thought to be pests. It overwinters as an adult, and new bugs emerge from August to October. What I haven’t found is any convincing reason for the creature to be named after cinnamon. One theory is that it emits a spicy smell if handled, but I’m having trouble squaring that with it belonging to the scentless bug family. Cinnamon comes from the inner bark of various trees, so I’m thinking that this little chap doesn’t have the jaws necessary to feast on it. Who knows? If you have any ideas, let me know. I’m just really impressed with his red and black livery, and easy-going nature. Who knows what other insects will fly in? I shall keep you posted.

What Does Climate Change Mean For Bumblebees?

Dear Readers, there has been quite a lot of research on the subject of bumblebees and climate change. After all, one look at these large, ‘furry’ insects is enough for me to worry about them buzzing about wearing the equivalent of a mink coat. They are, in fact, adapted for tundra conditions – their large size relative to pollinators like honeybees means that they lose heat more slowly than smaller insects (remember that surface area to volume ratio thing that many of us learned in O-Level biology). The ‘fur’ (actually outgrowths of the abdomen and thorax called setae) helps to insulate the bee against cold temperatures, and the bees also have very large flight muscles, which they can warm up by vibrating them – bumblebees are often the only pollinators in flight on a cold morning, and queens can sometimes be seen foraging as early as January in the UK. They also, unusually for insects, can generate their own body heat – they use enzymes that can break down the sugars found in nectar to help them to warm up. The queen in the photo below was spotted on my birthday, 20th January, earlier this year.

Bumblebees generally have one generation per year. In the spring, a queen bumblebee comes out of hibernation, and sets off to find a spot for her nest – you will often see large bumblebees flying low over the grass as if looking for something. A mousehole, dense ivy or a gap under a shed are all desirable spots. Once in her nest, the queen lays her first few eggs, and feeds them all by herself until they hatch as workers and are able to forage themselves. Eventually, there are enough workers for the queen to concentrate on laying her eggs. The colony will comprise less than 1000 individuals, and towards the end of summer the queen will start to lay eggs that will develop into fertile queens, and males. These will leave the nest and mate. The queens, already pregnant, will find a space to hibernate, and the males, the original queen and the rest of the workers will die.

So, bumblebees are basically big and hairy in order to survive in cold climates. How, then, are they doing in the heat?

It’s true that there are bumblebees in tropical and sub-tropical habitats, but these are mostly found at high altitude, where it’s colder, and  they tend to be smaller, meaning that they can lose heat more easily. However, the bumblebee species found in southern Europe and the southern USA are thought to be pretty much at the edge of their range, and are expected to disappear as the summers get hotter and drier, and the winters milder.

For bumblebees in the UK the effects of climate change will depend on the rapidity of change, and intensity of individual events. At over 37 degrees Centigrade, bumblebees forage much less effectively. Queens have something called heat stress proteins, which can protect them against extremes of temperature while they’re hibernating, but workers and males do not have these proteins, as far as we can tell. Bumblebees are also prone to water-stress (desiccation) – one thing that I did during the extreme heat of the past few days/weeks was put out a dish almost full of gravel, and then topped up with water so that insects could land safely and drink.

Bumblebees are tough, adaptable creatures ( I often think of them as the Einsteins of the insect world) and they have a number of behaviours that help during extreme weather conditions. Bumblebee nests are tiny compared to those of honeybees (under a thousand individuals as opposed to tens of thousands), but the workers will club together to  vibrate their wings to try to keep the temperature between 28 and 32 degrees Centigrade. They will also change their foraging behaviour during hot spells, going out in the early morning and later in the day to avoid the heat of midday. Bumblebees also seem to be choosing more isolated, cooler spots in order to make their nests.

However, finding those cooler, more isolated spots is clearly becoming more problematic due to a combination of our habit of paving over our gardens,  using fake grass ( a particular bugbear of mine), agricultural intensification, deforestation and urbanisation. Some bees are migrating to try to find better habitat, and others are seeking spots at higher altitudes, as are many other animals and plants that are adapted to colder conditions. One important  question is ‘what happens when the temperature in mountainous habitats also rises?’

So, how are the bees coping so far? One interesting adaptation seems to be that some buff-tailed bumblebee colonies are surviving through the winter in the UK – presumably people are planting enough winter-flowering honeysuckle and mahonia to enable the colony to survive on iron rations until the spring comes. This may be preferable in some circumstances to a situation where a hibernating queen keeps waking up during the winter and hence burns through the fat reserves that would normally be used to produce her first few eggs. However, a non-hibernating queen will also produce fewer workers, so it may be a trade-off against different conditions.

Climate change is also affecting the delicate balance between the different stages of the bumblebee life cycle and the emergence of the flowers that they rely on – it’s clear that plants are flowering earlier than they used to, which may favour colonies that keep going through the winter, and fortunately many species of bumblebee in the UK can feed on a variety of different kinds of plants, so they will not be as affected as some of the bee species which are more specific in their requirements.

The bottom line is that bumblebees probably can adapt to the higher temperatures of climate change, but only up to a point, and only if there is enough genetic diversity for those adaptive factors to be present in the community of bees. Like animals trapped on islands, bumblebees are increasingly isolated from one another, trapped in small areas of botanical plenty while surrounded by deserts of concrete and agricultural monoculture. The idea of ‘pollinator pathways’, whereby bees of all kinds can forage more widely and can meet and mate with bees that they wouldn’t otherwise meet, is an important one, and it depends on everything from the planting of bee-friendly street trees to putting a pot of lavender or rosemary on the balcony. Will it be enough? Only time will tell.

Common carder bumblebee on bittersweet

This piece is largely taken from ‘Bumblebee resilience to climate change, through plastic and adaptive responses’ by Maebe et al, published in June 2021. The abstract is available here though it looks as if you might need access to a university library (or $15) to read the whole thing. Shout if there’s anything that you want me to look at in more detail – this is a meaty piece of work, and I have tried to precis it. 

I also found this article interesting, especially on the subject of  bee body size and mountainous habitats. 

An Old Friend

Fencepost jumping spider (Marpissa muscosa)

Dear Readers, I was talking to my friend J about tattoos at lunch today. At the age of 60 she is planning on getting one in the shape of a swift, and so the conversation turned to what I would have, in the event that I decide to be artistically punctured with lots of small needles.

“A jumping spider”, I said, without any hesitation. And therein hangs a tale.

When I was six or seven, I was out in our tiny garden as usual. I had spotted a tiny creature on the concrete slab that housed the giant post for our washing line, and I had noticed that it was acting very strangely, so I lay on my stomach (in my best party dress as we were supposed to be going out) and realised that the animal was a spider about the size of my fingernail. A few inches away on the slab, a house fly was cleaning its eyes with its hairy front legs, rotating its whole head by about 240 degrees like they do. The spider was prowling ever closer, using the lumps and bumps in the surface of the concrete as cover. Then, it paddled its legs, tensed itself and leapt through the air onto the back of the fly.

And in that moment was Bugwoman born. Because I don’t think I had ever seen anything quite so thrilling or so unexpected, and it opened my eyes to a whole world of astonishment and good old-fashioned awe.

Back to the present day, and I was getting some cushions for the chairs in the garden out of the cupboard when I noticed this little chap. And I am quite sure he was a chap because those ‘boxing gloves’ are pedipalps, which he uses to insert his sperm into a female spider if she is willing to accept him, though my lovely friends at the British Spiders Facebook Page tell me that this is just a young male, as in adults those pedipalps would be more formed, and his stripes would be more defined.

Jumping spiders don’t use webs or any of that namby-pamby stuff – though they will anchor themselves to the ground with a silk line before they spring, just in case the jump fails. They are hunters through and through, and so they have those astonishingly large eyes at the front of their faces which help them to judge distance. The slightly smaller eyes which are further back are used to detect motion.

Most invertebrates, including most spiders, seem broadly oblivious to human presence, moving away when they sense a shadow or hear the vibration of footsteps, but jumping spiders actually look at you. They may even cock their heads like attentive dogs. To me, they are utterly adorable, and much easier to love than some of the bigger, hairier, danglier spiders that you might encounter in a shed. You are not supposed to have favourites, but I confess that these creatures fill me with a warm glow. Here’s a short film of this little chap.

Jumping spiders will also chase a laser pointer in much the same way as cats do. They probably have tetrachromic colour vision (which is better than our colour vision) and they also have high-sensitivity to ultraviolet light. They live in a colourful world, for sure, and in experiments they’ve been shown to be able to learn, remember and recognise particular colours.

Jumping spider chases laser pointer

Although this particular jumping spider is not very brightly coloured, the family to which he belongs (the Salticidae) are extremely varied, with over 6000 species, including the peacock spiders. You may well have come across them before, but if not, have a look at this extraordinary BBC film . Such tiny creatures, with such complex lives! It just reminds me of how little we actually know about the animals and plants that we share the planet with.

And so, I persuaded the jumping spider onto the fencepost for which he is named. Hopefully he’ll find a female jumping spider. At the very least, he’ll be able to find some insects to munch on. Good luck, little chap.

A Spring Walk in St Pancras and Islington Cemetery

Dear Readers, three weeks after the onset of my Covid I’m finally feeling like myself again, and so it was such a joy to head out to St Pancras and Islington Cemetery to take in the glory of the Lesser Celandine. Just look at them! Could they be any more joyful, I ask myself.

And if you watch closely, you can see them being appreciated by a whole mass of bees and tiny pollinators.

The primroses are out in force too.

I heard the buzzards mewing, and saw one being hotly pursued by the usual gang of crows. And, for your delectation, here is a sparrowhawk’s backside, shortly before she exited stage left, also pursued by crows. Note those distinctive bars on the stomach.

Blackcaps were singing their heads off, as was this chaffinch, who was making a most uncharacteristic volume of sound.

And the blackthorn is in flower.

I have mentioned before that the lesser celandine was Wordsworth’s favourite flower, but I’d never read the poem that he composed to it. I had expected some cheery paean to the first flower of spring but, as so often with Wordsworth it’s rather more thoughtful than that. So here, for your delectation, is Wordworth’s Lesser Celandine. See what you think.

The Lesser Celandine

There is a Flower, the Lesser Celandine,
That shrinks, like many more, from cold and rain;
And, the first moment that the sun may shine,
Bright as the sun himself, ’tis out again!

When hailstones have been falling, swarm on swarm,
Or blasts the green field and the trees distressed,
Oft have I seen it muffled up from harm,
In close self-shelter, like a Thing at rest.

But lately, one rough day, this Flower I passed,
And recognized it, though an altered form,
Now standing forth an offering to the blast,
And buffeted at will by rain and storm.

I stopped, and said, with inly-muttered voice,
“It doth not love the shower, nor seek the cold:
This neither is its courage nor its choice,
But its necessity in being old.

“The sunshine may not cheer it, nor the dew;
It cannot help itself in its decay;
Stiff in its members, withered, changed of hue.”
And, in my spleen, I smiled that it was grey.

To be a Prodigal’s Favourite -then, worse truth,
A Miser’s Pensioner -behold our lot!
O Man, that from thy fair and shining youth
Age might but take the things Youth needed not!

William Wordsworth (1770-1850)

The Mosquitoes of the London Underground

Photo One by Walkabout12 - Own work, CC BY-SA 3.0, Walkabout12 - Own work, CC BY-SA 3.0,

The London Underground Mosquito (Culex pipiens f. molestus)(Photo One)

Dear Readers, I was much taken by an article in New Scientist about the evolution of urban species by Rob Dunn this week, and in particular his thoughts about the infamous London Underground mosquito. During the Second World War, unfortunate civilians who spent nights on the platforms of Underground stations to avoid the Blitz complained about being bitten unmercifully, but it’s only recently that genetic technology has advanced to a point where we can really work out what’s going on.

Photo Two by By US Govt - This media is available in the holdings of the National Archives and Records Administration, cataloged under the National Archives Identifier (NAID) 195768., Public Domain,

Sheltering in the Underground (Photo Two)

The original LU Mosquito came from the Fertile Crescent in the Middle East and lived above ground. These insects are active only during the warmer months, require a meal of blood before they can reproduce, and feed mainly on the blood of birds. However, as the mosquito spread north into colder climes, it survived by living in cities, particularly their underground regions such as sewers. The insect evolved new genetic characteristics, such as odour recognition, digestion and immunity, that would be useful in environments rich in organic waste.

However, it wasn’t just the genes that changed, behaviour did too. Both the underground and the above-ground mosquitoes are thought to be the same species, but the underground ones are active all year round, can reproduce without a blood meal, and prefer to feed on mammals: rats and mice in particular, but humans where they can find them. The underground mosquitoes are isolated from other mosquitoes, and their habitat can be compared to an island, as Dunn points out: the mosquitoes cannot disperse, and so they become more and more specialised. Cities such as Paris, Minsk, Tokyo and New York all have their own ‘Underground Mosquitoes’.

However, the isolation can have another, even more extreme, effect – it’s been shown that where LU Mosquito populations are isolated within the Underground network, they can start to become genetically distinct from one another. So, it was found that the mosquitoes found on the Victoria Line were different from those found on the Bakerloo Line. It’s quite possible that every underground line could have its own mosquito, though I suspect that lines with a larger proportion of stations which are above ground might be less distinct, because their mosquitoes can actually disperse and interbreed.

For us, though, as humans, it means that the old Petula Clark song ‘Don’t Sleep in the Subway’ has never been better advice.



The Secret Life of Flies by Erica McAlister

Dear Readers, this isn’t exactly a book review (yet) because I am only up to page 57 of this rather splendid book. However, it is so full of interesting factoids that I wanted to share a few with you, even though I am in the middle of year end and things are a bit on the frantic side (understatement). So, please forgive me for a few quick bullet points. There are more fly-related things to be said in the future, I’m sure.

First up, McAlister estimates that there are 17 million flies for every single human being currently walking about on the planet. They are a hugely diverse family, from craneflies and hoverflies to bluebottles and horseflies. But, as she puts it ‘The question you still want answering is: what have all those flies ever done for us?’

The obvious first answer is that we would be up to our ears and above in waste if it wasn’t for flies, but flies are extremely undervalued as pollinators. For example, there is only one group of tiny flies that can pollinate Theobroma cacao, otherwise known as the chocolate plant. These are known in the Caribbean as No See Ums, and I remember my Dad talking about how badly some members of this family of midges could bite. The chocolate midge (Forcipomyia sp.) manages to pollinate the flowers of the chocolate plant, but it is a very particular little creature, preferring damp, shady woodlands and moist soil or a pond to raise their youngsters. The cutting down  of forests to plant larger and larger chocolate plantations is, ironically, destroying the habitat preferred by the crop’s only pollinator. Could this be the end of the Curly Wurly? Only time will tell.

A chocolate midge (Forcipomyia sp.) (Photo by© Christophe Quintin Via Flickr (CC BY-NC 2.0)

Like many pollinators. flies and flowering plants have evolved alongside one another, and this has led to some most intriguing designs, none more so than that of Moegistrorhyncus longirostris, a fly which has a proboscis eight times longer than its body. If a human had a tongue of equal ratio, it would be over six metres long. Why the long tongue? Well, eight species of plants on the Cape in South Africa can only be pollinated by this fly or one that’s closely related, because they have such long tubes that only the longest-tongued can reach their pollen.

Just the kind of flower that longirostris feeds on…

And so I am very much enjoying this book, as you would expect from someone with a name like Bugwoman (though flies are not bugs in the technical sense of course). I am sure there will be more highlights later!

A Damp Walk in St Pancras and Islington Cemetery

Dear Readers, I was in the mood for a brisk walk on Saturday – the fog had just cleared but it was a damp, dreary day that didn’t really encourage my usual drifting along. So it was not until I reached the ladies ‘convenience’ on the far side of the cemetery that something finally caught my eye. What was this in the corner of the building? Well, it appears to be a group of hibernating harlequin ladybirds (they are much too large to be any other species). I love the way that the ones in the middle have piled on top of one another for warmth. I am slightly surprised that they haven’t woken up yet, what with it being so mild, but maybe they know something that I don’t. There certainly aren’t many greenfly about yet, and as that’s mainly what they eat, maybe it makes sense to snooze on for a little longer.

There was lots of crow activity today – this magpie was throwing the leaves about in much the same way that a blackbird does. I think it gives an indication of how many invertebrates use the leaf litter as a place to spend the winter, and how important it is to leave at least some leaf piles in the garden.

The crows are super-curious, and are always investigating the graves to see if there’s anything edible. I sometimes see them picking up the artificial flowers and then throwing them over their shoulders as if in frustration. This one eventually flew off with what looked like a chrysanthemum flower. Maybe there are some seeds or insects inside. The magpies will also take shiny objects and fly off with them, so the old adage about magpies being ‘collectors’ still seems to hold true.

The first primroses are starting to emerge…

And there are still some rather damp-looking fungi around.

Mystery fungus! All suggestions welcome.

But what does this hogweed think it’s doing? It’s at least four months too early. It was flowering away in splendid isolation, with not a single fly to pollinate it. There were a few winter gnats around, but as far as I know they don’t act as pollinators. This is a high risk strategy, but as the winters get milder, who knows whether early-flowering plants might be the winners in the end?

And finally, we were accosted by this enormous squirrel. I am 99% sure that she is pregnant, rather than just well-cushioned – I noticed squirrel mating behaviour back in December, so although she’s a bit early, she’s not that unusual. I imagine that there’s lots to eat in the cemetery, so let’s hope that she gets enough nutrition to provide for her kits. She looks in excellent condition.

And so it’s back home, to get stuck into the chemistry module of my Open University degree. Studying the Periodic Table reminds me of why I loved chemistry at school – what an elegant and precise way of starting to understand the material world it is! No doubt I shall be waxing lyrical about it soon. For now, I’m just grateful for the way that science provides a way of asking questions about the world that is calm and rational. It feels like just the bracing intellectual exercise that I need.

A Moth Like a T-Bar

Beautiful Plume Moth (Amblyptilia acanthadactyla)

Dear Readers, I am always happy to see a plume moth, especially as the last one that ventured in was squashed by my cat – I only wish she had such success with the clothes moths. You might be more familiar with the Hemp-Agrimony Plume moth (Adaina microdactyla) or maybe that’s just me, what with having the plant in the garden. I always find these sitting on the front door.

Photo One by This image is created by user Wouter van der Ham at, a source of nature observations in the Netherlands., CC BY 3.0 <>, via Wikimedia Commons

Hemp-Agrimony Plume Moth (Adaina microdactyla) (Photo One)

The wings are unusually constructed, as you can see – at rest the wings are rolled up like a Venetian blind. Plume moths are closely related to the many-plumed moths, which take the wing construction to a whole new level –  (Alucita hexadactyla) has wings that look like feathers.

Many plumed moth (Alucita hexadactyla)

Although these wings probably aren’t ideal for flight, they do seem to be useful for camouflage – both the beautiful plumed moth and the hemp-agrimony plume moth look like pieces of dead grass when they are in their natural habitat. Alas, they are rather more noticeable against a plain wall, as my cat will attest.

The beautiful plumed moth on my kitchen wall is probably looking for a place to hibernate, as the adult moths spend the winter dozing away, before heading off in spring to mate and lay its eggs. The larvae have wide and varied tastes, and will munch on mints, thistles, heathers and geraniums, but rarely reach pest status in this country. Besides, my water mint has gone berserk this year, so if these little critters will keep it all in check I will be only too happy.

Sunday Quiz – Aliens!

A Martian in Woking (Photo by Colin Smith ) This is a metal sculpture, based on H G Well’s book ‘The War of the Worlds’

Dear Readers, this week we had Claire with 11 1/2 out of 15 and Fran and Bobby Freelove with 13 1/2 out of 15, so well done to all of you! The next quiz will be tomorrow, and I am wondering why I didn’t have the idea for it ages ago…I hope you enjoy it!

‘Alien’ animals can cause a range of reactions, but the history of how they got to the UK, and what their impact has been, fascinates me. In most cases, they arrived because we wanted them, and didn’t realise quite how keen they’d be to get back to the wild. Sometimes, they were hitchhikers, a result of the international trade in plants and artefacts. Very rarely, they flew here of their own accord and found the conditions to their liking. With climate change, and with our inadequate biosecurity regulations, we are going to have to get used to all manner of plants and animals arriving and setting up home. As always, it will be interesting to see how such encounters play out.

Photo One by Bouke ten Cate, CC BY-SA 4.0 <>, via Wikimedia Commons

1. Edible dormouse (Glis glis)

This attractive little rodent was deliberately released into the wild in 1902 (it comes originally from southern and central Europe). It is considered a menace because it can wreak havoc in lofts and roof spaces, and damages trees by stripping the bark. The Romans used to have special pots for keeping edible dormice until they were fat enough to eat. I must admit I thought that they had brought them to the UK, but it seems that if so they became extinct, and were re-introduced much more recently.

Photo Two by Ryzhkov Sergey, CC BY-SA 4.0 <>, via Wikimedia Commons

2. American mink (Neovison vison)

Farmed for their fur, some escaped while others were deliberately released, sometimes by well-meaning animal activists. However, these creatures are efficient predators, and their presence has been linked to the decline of the water vole and various ground-nesting birds. Their numbers might be decreasing slightly as the larger otter becomes more common.

Photo Three by Lilly M, CC BY-SA 3.0 <>, via Wikimedia Commons

3. Sika deer

Originally introduced to populate the grounds of stately homes and estates, the sika was established in the wild by the 1930’s. It interbreeds with native red deer and can cause serious damage to crops, trees and sensitive habitats. There are lots in Dorset, and on our way back from Dorset last week our train nearly ran over two who were on the tracks.

Photo Four by Prue Simmons, CC BY 2.0 <>, via Wikimedia Commons

4. Racoon Dog (Nyctereutes procyonoides)

This animal (which is a canid not a raccoon) was introduced to the UK from East Asia for its fur. it isn’t established in the UK yet, but it is well established in many other parts of Europe so watch this space. Where it has established a foothold, it is a predator of birds and amphibians, and competes with native carnivores such as the fox and badger.

Photo Five by Bernard Spragg. NZ from Christchurch, New Zealand, CC0, via Wikimedia Commons

5. Ring-necked/rose-ringed parakeet (Psittacula krameri)

Did Jimi Hendrix release a pair of these while he was on an acid trip, resulting in the many thousands of birds that are now common in London? It’s more likely that there were escapes and releases from multiple sites over a period of years. At any rate, the parrot is now moving north and west at an inexorable rate. It strips orchards and may compete with other hole-nesting birds, but personally I think that it brings a touch of the exotic to North London.

Photo Six by By Andreas Trepte - Own work, CC BY-SA 2.5,

6. Egyptian Goose (Alopochen aegyptiacus)

This medium-sized goose has been breeding in the wild after escaping from wild fowl collections since the early 1800’s, but has increased like billy-o since the 1980’s. It is well-established in the wild in Suffolk and Norfolk, and seems to be going west at a rate of knots. It can cause crop damage and pollute water bodies, but to be honest so can most wildfowl at high concentrations. Plus, to be complaining about pollution of water bodies when there’s so much agricultural and industrial run-off seems a bit hypocritical. Interestingly, they often seem to nest in hollow trees, which is quite a feat for a large aquatic bird.

Photo Seven by By Rhondle - Own work, CC BY-SA 3.0,

7. Red-eared terrapin (Trachemys scripta elegans)

I was only writing about these animals earlier this week. They can’t breed in the UK (yet) because the winters are still too cold, but individuals can live for up to thirty years, and there seems to be no limit to the number of people prepared to throw their pets into the nearest water body when they get too big. They are voracious predators of amphibians and invertebrates, even taking ducklings when they are tiny.

Photo Eight by Charles J. Sharp, CC BY-SA 4.0 <>, via Wikimedia Commons

8. Marsh Frog  (Pelophylax ridibundus)

Deliberately introduced by the end of the 19th century, this chap is also known as the laughing frog because of his loud call. The frog is now well-established in Romney Marsh in Kent, the Somerset levels and the area around Tamworth. The species is apparently becoming more common, so keep an eye open….

Photo Nine by Dieter Florian (To contact the author, ask the uploader or take a look at, CC BY-SA 3.0 DE <>, via Wikimedia Commons

9. Wels catfish (Siluris glanis)

This enormous fish, which can grow to 5 metres long and weigh 300kg, was deliberately introduced as a food fish. Hah! By the 1950’s it was swimming happily in managed stillwaters used by fisheries, and in some deep lowland rivers. It eats anything and everything, from frogs to water voles to ducks, and as you can see, there’s nothing in UK rivers that can outcompete it.

Photo Ten by Liquid Art, CC BY-SA 4.0 <>, via Wikimedia Commons

10. Rainbow Trout (Oncorhyncus mykiss)

The trout that made river fish available to the general public when fish farming really took off in the 1970s in the UK, rainbow trout seem to have problems breeding in the wild in the UK, and are still usually out-competed by the local brown trout. However, climate may be a factor in keeping them in check, and this is changing as we know. Again, watch this space.

Photo Eleven by David Perez, CC BY 3.0 <>, via Wikimedia Commons

11. Signal Crayfish (Pacifastacus leniusculus)

Introduced from North America in the 1970s, this crayfish quickly found its way into the wild, and has caused the rapid decline of the native white-clawed crayfish through competition for food and other resources. It also spreads crayfish plague (who knew there was such a thing?) As if that wasn’t enough, it makes its burrows in the banks of water bodies, causing them to collapse, and eats the eggs and young of fish. There is a move afoot to persuade the UK public to eat more crayfish.

Photo Twelve by David Short from Windsor, UK, CC BY 2.0 <>, via Wikimedia Commons

12. Harlequin ladybird

This much-maligned beetle comes originally from Asia, and was deliberately released in Europe as a biological control, presumably against aphids. Sadly, the harlequin ladybird is much more of a generalist predator than that, and when the aphids are gone it will turn its attentions to other insects, including the much smaller native ladybirds. It arrived in the UK in 2004 and made itself very much at home ever since. I think personally that it outcompetes other ladybirds than rather than actually eating them, but that’s anecdotal, based on a couple of years observation of one aphid-infested buddleia.

Photo Thirteen by Charles J. Sharp, CC BY-SA 4.0 <>, via Wikimedia Commons

13. Asian hornet (Vespa volutina)

Oh lord the column inches devoted to this insect! It is true that it eats honeybees, but I suspect that it has been the cause of the death of more European hornets, hoverflies, wasps and native bees than any other creature. It is seen fairly regularly in the Channel Islands now, and I believe it’s also been spotted in Cornwall. It arrived in south-western France in some pots imported from Asia. It’s most likely to be spotted in areas where honeybees are kept, but it is still very unlikely to be seen in most of the UK. It is much darker in colour than our native hornet.

Photo Fourteen by David Short from Windsor, UK, CC BY 2.0 <>, via Wikimedia Commons

14. Horse chestnut leaf miner moth (Cameraria ohridella)

This is the tiny creature responsible for our horse chestnut leaves become dry and crinkly and dropping off early every year. Little is known about it, except that it arrived as recently as 2002 on some imported plants, and has been spreading north and west ever since. Though it makes the trees look ugly, it doesn’t yet appear to affect their long-term health.

Photo Fifteen by Kleuske, CC BY-SA 3.0 <>, via Wikimedia Commons

15. Oak processionary moth caterpillars (Thaumetopoea processionea)

This little darling appeared in 2006 as a contaminant of imported plants and trees – it’s native to northern France. London appears to be the epicentre of its population at the moment, maybe because of a concentration of oak and hornbeam forest, which it seems to like (our local Coldfall and Cherry Tree woods have both had infestations recently). The insect can be a major defoliator of trees, and its hairs can cause allergic reactions and skin irritation. It can also cause the eradication of populations of innocent caterpillars such as those of the ermine moth (which forms nets in bird cherry and some other trees, but causes no long term harm). Don’t just take a flamethrower to your tree, people!

Photo Credits

Photo One by Bouke ten Cate, CC BY-SA 4.0 <>, via Wikimedia Commons

Photo Two by Ryzhkov Sergey, CC BY-SA 4.0 <>, via Wikimedia Commons

Photo Three by Lilly M, CC BY-SA 3.0 <>, via Wikimedia Commons

Photo Four by Prue Simmons, CC BY 2.0 <>, via Wikimedia Commons

Photo Five by Bernard Spragg. NZ from Christchurch, New Zealand, CC0, via Wikimedia Commons

Photo Six  By Andreas Trepte – Own work, CC BY-SA 2.5,

Photo Seven By Rhondle – Own work, CC BY-SA 3.0,

Photo Eight by Charles J. Sharp, CC BY-SA 4.0 <>, via Wikimedia Commons

Photo Nine by Dieter Florian (To contact the author, ask the uploader or take a look at, CC BY-SA 3.0 DE <>, via Wikimedia Commons

Photo Ten by Liquid Art, CC BY-SA 4.0 <>, via Wikimedia Commons

Photo Eleven by David Perez, CC BY 3.0 <>, via Wikimedia Commons

Photo Twelve by David Short from Windsor, UK, CC BY 2.0 <>, via Wikimedia Commons

Photo Thirteen by Charles J. Sharp, CC BY-SA 4.0 <>, via Wikimedia Commons

Photo Fourteen by David Short from Windsor, UK, CC BY 2.0 <>, via Wikimedia Commons

Photo Fifteen by Kleuske, CC BY-SA 3.0 <>, via Wikimedia Commons