The Saxons are invading again

In July 1987, Dolichovespula saxonica, commonly known as the Saxon wasp, was first recorded in the UK at Juniper Hall in Surrey. In the 32 years that has since passed, the species has spread throughout south-eastern England, with scattered records further north to Yorkshire and a handful of sightings from Scotland. Eventually, at the end of July this year, I saw my first ever Saxon wasp, in the same county it was first seen. It is one of two social wasp species which have colonised the UK in modern times, along with Dolichovespula media, the median wasp, which was first found by Steven Falk in 1980 in Sussex.

Contrary to what many people might expect, there are several thousand wasp species in the UK, ranging from tiny parasitic wasps which barely reach 0.2mm in length to the docile hornet. Most of these wasps are solitary, and the social wasps comprise only about 1% of all the world’s wasp species. They’re mainly restricted to the subfamily Vespinae, which has around 11 members in the UK.

My recent sighting of the Saxon wasp came as quite a surprise to me. In the past few weeks I’ve been noticing more broad-leaved helleborines Epipactis helleborine (a species of orchid) than I usually do in my local area. They like to grow beside paths within woodland, perhaps due to the increased amount of light that reaches their leaves in comparison to the centre of the dense woodland. As a result, they are one of the most frequently encountered orchids in my region. However, despite their frequency, before I found my first Saxon wasp I had never observed any pollinators visiting these orchids.

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A spike of the broad-leaved helleborine on my neighbour’s verge

As you can see from the photo, their flowers are not particularly attractive colour-wise. Many other orchid species have evolved to mimic their pollinators, so that they are not drawn to the flowers by the promise of a meal but by the promise of a mate; as a bee, for example, attempts to mate with the flower of a bee orchid, pollination will take place. Moreover, the flowers emit a scent mimicking the pheromones emitted by the female bee, attracting the pollinating bees from far afield. This may sound clever, however reducing your number of pollinators to just one or a handful of species greatly restricts spread. Indeed, in southern England, the pollinator of the bee orchid is quite rare, and most of the time the bee orchid reproduces by self-pollination.

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The early spider-orchid, despite its name, has evolved to mimic the mining bee Andrena nigroaenea. I can’t personally see the similarity, but perhaps the bees can.

However, the broad-leaved helleborine does it slightly differently. Its primary pollinators are social wasps, such as the common wasp Vespa vulgaris (one’s standard picnic-botherer) as well as the Saxon wasp. Like many flowers it produces a nectar to entice the wasps in. However, once the wasps have arrived at the orchid flowers, they begin to become intoxicated by traces of opioids within the nectar. The narcotic-like qualities of the nectar cause the wasp to sleepily visit all of the flowers on the orchid multiple times, to ensure that all the pollinia from the flowers are transferred. I like to think that the opioids are also addictive to the wasps to encourage them to visit other broad-leaved helleborines, but I’m not sure whether this has been studied yet!

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A drugged Saxon wasp walking between helleborine flowers.

In the photo of the wasp above, it is quite easy to see a number of white objects on the face of the insect. These are the pollinia of the orchid, which stick to the face of the wasp after it has visited each flower trying to reach the nectar within. Each individual flower only has a few pollinia, which is the whole product of an anther. It is a coherent mass of pollen which is attached to the flower by a stipe (or stalk) and has a sticky disk on the other end which attaches to the face of the insect. Ideally, the insect then transfers these masses of pollinia to another plant, where the pollen in the pollinia will be transferred to the stigmata, completing pollination.

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The wasp reaching into a helleborine flower, looking for nectar. The pollinia can be seen just above the thorax of the wasp, attached to the roof of the flower, ready to attach to the wasp. 

It was fascinating to document this sighting, which was two firsts in one: my first Saxon wasp, and my first observation of pollinia in action. I’ll be keeping an eye on the helleborines this summer to see if any other wasps are enticed to the flowers by the sweet nectar and drugs!

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I smell a rat

16th July, World Snake Day

The region of southern Ontario where I was lucky enough to be able to stay for a couple of weeks in the first half of July holds an important yet threatened population of the Gray Ratsnake, Pantherophis spiloides. While participating in the memorable BIOSPHERE Youth Environmental Leadership Expedition at the Queen’s University Biological Station (QUBS) on the shores of Lake Opinicon, the enthusiastic program leader Dr. Shelley Ball interrupted our dinner one evening with a Gray Ratsnake she had just hand-caught. Perhaps one of the few things I will stop dinner for!

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Gray Ratsnake being held by Shelley

Gray Ratsnakes are one of Canada’s largest snakes. They are the largest in terms of length, with adult able to reach over six feet from head to tail, but are pipped by Bullsnakes with regard to mass.

During the expedition at QUBS, we were treated to a short presentation by Matt and Meg who are working on how to prevent the decline of this sizeable snake. One of the leading causes of fatalities in this species is road collisions. The dark colouration of the ratsnakes means that they are often mistaken for the shadows of overhead branches on roads, and are therefore not noticed by motorists. Even when they are recognised as snakes drivers have a hard time avoiding them, as due to their length they can easily stretch across the entire width of the road.

On account of this, Matt and Meg are working on avoiding these snake RTAs by reducing the incidences of snakes crossing the road. They are helping to develop snake-proof fences which aim to guide the snakes to specially-built culverts which they can use to get to the other side of the road without risking being hit. Gray Ratsnakes are semi-arboreal and spend lots of their time in trees, so are adept climbers. The fences to be implemented, therefore, need to be resistant to climbing by these agile snakes. Creating fences that not even ratsnakes can ascend also prevents a wide variety of other wildlife such as turtles from being hit and allows them to utilise the culverts as well.

Gray Ratsnakes are remarkably docile and are rarely aggressive when handheld. When threatened they do possess the abilility to release the contents of the cloaca, musking the assailant with a foul smell. However, the related Northern Water Snake behaves in this manner with far greater regularity. It, like the Gray Ratsnake, is non-venomous, so has to make itself as unappealing to predators as possible, by releasing both musk and excrement. Despite the lack of venom, the bites are still painful and the saliva of the Northern Water Snake has an anticoagulant which causes the bite to bleed more freely. However, although it might sound threatening, the water snake is another fascinating reptile.

I had the good fortune of glimpsing a Northern Water Snake on one occasion at QUBS as it swam past the boathouse. As its name suggests, it is a very strong swimmer. It will take sleeping fish at night in shallow water and during the day it will hunt other prey such as crayfish and amphibians among vegetation at the water’s edge.

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Northern Water Snake snaking through the water at the QUBS boathouse

To finish off this post for World Snake Day, I’ll mention the third species of snake we encountered on our expedition at QUBS, which was also the most numerous. The Common Garter Snake is, as its name suggests, frequent, but also fairly skittish. As a result, they are difficult reptiles to photograph. However, nearing the end of the expedition we disturbed one from a pile of dead leaves near the library. It retreated to a stone wall, from which it poked its head out to survey the scene, giving a rare opportunity to photograph this species.

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A curious Common Garter Snake.

The Common Garter Snake, like all but one snake in Ontario, is another non-venomous species. Snakes are often misrepresented as being solely dangerous creatures. However, less than a fifth of the world’s snake species are considered a threat to human health, with very few venomous snakes being found in the more populated temperature regions of the world. Instead of being feared, snakes should be more appreciated for their incredible diversity and fascinating range of habits.

The Glue Pistons

For a long time I’ve been wanting to be involved in a recording scheme. Yet I had not quite appreciated the amount of work that is involved in managing what is often a massive collection of records. Over the past few months I’ve been collating the records of springtails (Collembola) from Surrey, which has been a big challenge, even with springtails being one of the least recorded invertebrate groups in the country.

Springtails are often tiny arthropods with six legs. Whether they’re insects or not is up to debate however. Most authorities currently class them as Entognatha, with reference to their internal mouthparts; in contrast to the external mouthparts of insects. However, the other two members of the Entognatha – Protura and Diplura – are just as closely related to springtails as they are to insects.

Another anatomical feature of springtails is the collophore located on the underside of the abdomen, after which they get their scientific name, which means ‘glue piston’. It takes the form of a tube pointing downwards from the ventral side of the first abdominal segment. Originally, it was thought to help to stabilise the animal, although it is now believed to play a part in maintaining the water content of the body.

Springtails get their common name from the furca, a long, forked organ which originates from the end of the abdomen and is often bent under the body. It is used primarily to escape predators, and can fling the springtail at incredible speeds away from danger. However, where and how the animal lands is unpredictable. Some species, such as Ceratophysella bengtssoni, have an inflatable sac on the antennae with which the springtail can adhere to the surface it lands on. Some species have only vestigial furcas or lack one entirely, often in species which live in habitats such as compact soil where the furca would inhibit the movement of the springtail, or those which live near the sea or flowing water, where an unpredictable jump could land them in an even more dangerous situation.

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Brachystomella parvula. Springtails can vary greatly in shape, this being one of the stout, pudgy Poduromorphs.

The best literature for identification is the FSC key written by the late Steve Hopkin, A Key to the Collembola (Springtails) of Britain and Ireland. This provides a complete key to all the described species thought to be present in the British Isles and is relatively recent (2007). Otherwise, there are a few good websites that can be found online, such as www.collembola.org, which has many good-quality images.

If anyone finds and identifies any springtails, I’m sure the co-ordinator of the Collembola Recording Scheme, Dr Peter Shaw, would be happy to receive any records. His details can be found here. And if anyone records any from Surrey, I’d love to hear from you so I can add the records to my growing database. You can contact me using the form under the ‘Feedback/Contact’ page on my blog. I’d also be happy to receive any unidentified specimens in need of ID.

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Willowsia platani (possibly var. nigromaculata). One of the Entomobryomorphs: comparatively long, slender springtails.

Goldeneye, in lichen form

Running backwards into the Devils Dyke Pub to get out of the fierce hail certainly wasn’t the intended end to today’s outing. We had been caught out on a grand scale; a band of completely unforecast precipitation left our clothes so sodden that not even a hot chocolate and four-cheese pizza could warm me up. But was it worth it?

Birders may be used to the sight of a goldeneye floating out on a windswept gravel pit or reservoir at this time of year. Although the diving duck breed in trees, the nesting sites are solely in cavities in larger trunks and at latitudes further north than the UK. So, how many British birders can say that they’ve seen a goldeneye in a tree? I doubt many of them – yet as of this morning I can, but not sensu stricto.

The goldeneye lichen, Teloschistes chrysophthalmus, is named after the bright orange apothecia borne on blue-tinged stalks. The apothecia are disks containing the asci, which in turn contain the spores which will be carried on the wind to colonise new sites. Indeed, this is likely to be how the goldeneye lichen arrived in the UK. In the 19th century there were several sporadic records along the South Coast, and this decreased to only two in the 20th century. Yet, since 2007, recolonisation has been in full swing and there have been records from most South Coast counties along with an outlier in Herefordshire. It is still a fairly rare species, but definitely on the increase. It is not completely known what might be driving the recolonisation. Increasing temperatures could be a factor, yet in the early 19th century when well-established populations could be found in the south, it was relatively much colder than modern times.

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The bright orange apothecia really stood out on this drab, dull day

For this sighting I am indebted to @apeasbrain who first found the lichen last weekend and who provided brilliant directions (only the one individual plant has been found so far, like a needle in a haystack). However, it turned out that despite the lichen being the main instigator for my visit to Devils Dyke, it was not the only highlight. Just past the Hawthorn on which the lichen is growing, the path descends into a copse of Ash trees. On one of these trees I managed to spot some movement, out of the corner of my eye. At first glance I took it to be a ladybird larva, but I knew something wasn’t quite right. On arrival home, I realised it was in fact a pre-adult Endomychus coccineus, known vernacularly as the False Ladybird. This was a species I’d been wanting to see for months, so it’s a bit embarrassing that I didn’t recognise it immediately – but coupled with the Teloschistes, the incredibly painful scramble back to the pub once the hail set in was absolutely worth it.

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Teloschistes chrysophthalmus becomes my 100th lichen and Endomychus coccineus my 250th beetle. Together they put me on 69 new species for the year so far, a good pace I think!

Beluga in the Thames!

Contrary to my normal style, this blog post’s title is a little more self-explanatory than usual. This is so that when I’m scrolling through the archives in fifty years time I’ll be able to instantly recognise what this post will be about: something I’d never even considered possible.

If I was looking ahead to today from this point last week, I would probably be wondering how I’d managed to book a flight to Greenland or Svalbard at such short notice, and why it was a mild 17 degrees at such high latitudes. At the very least, I would be curious as to where I’d sourced my drugs from. I cannot believe that this morning I was enjoying a plate of chips in the warm sun at a table outside the Ship & Lobster on Mark Lane in Gravesend, Kent, while behind me a Beluga surfaced, just behind a barge with the words ‘Working for the Tidal Thames’ inscribed on its side.

The whale was first found by Dave Andrews on Tuesday, and I imagine he must have had the shock of his life when he spotted it. I certainly would have, with this record constituting one of the most southerly records of this species in the world. Belugas have a circumpolar distribution, with the nearest populations to the UK being over 2500km away. I was surprised to find out that this is the 19th sighting of Belugas in UK waters, although they have chiefly been seen in the Hebrides, Shetland and Orkney, with outlying locations being off Northumberland and Northern Ireland, both in 2015.

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The stretch of the Thames where we saw the Beluga

Belugas are interesting among whales as they can easily tolerate brackish and even freshwater. They are quite at home in estuaries and during summer often travel hundreds of kilometres up rivers in search of fish. In the remote polar regions they usually inhabit, this is fairly risk-free. The Thames is something else, however. As you can see from the above photo, residing in the Thames is not without its dangers. During the short while we were watching the sub-adult Beluga, about half-a-dozen vessels passed right over where the Beluga was seen just minutes before including a couple of massive ships.

Although, ship strikes are not the only danger this whale may have to face. There is also, of course, a higher concentration of plastic in the river than it will be used to. If it ingests too much it will die a slow and painful death. No doubt the overall relatively balmy climate will have an effect, although I’m not sure exactly how. But if Belugas weren’t affected by warm temperatures, then they wouldn’t be restricted to such icy climes.

It will be interesting to see how this Beluga’s slight wander will pan out. The best case scenario is that it will be seen swimming downstream and into the North Sea, where its instincts will kick in and it will swim back north to where it ought to be. To finish this blog post, here is a video of the couple of times I managed to record ‘Benny the Beluga’ coming up for air (email subscribers may have to click through to the blog to view the video):

Coot-like coot-foot

Scientific names, often consisting of a mix of Greek and Latin, can sometimes be a little peculiar. For example, Phalaropus translates to coot-foot, and fulicarius to coot-like, to produce the scientific name for the Grey Phalarope. It isn’t really coot-like on outward appearance at all, only the feet as suggested in the generic name Phalaropus.

Phalaropes are waders, but are unusual among the group as they have partially webbed feet (like coots). This allows them not only to feed along the muddy margins of wetlands but also to lead a pelagic lifestyle, often congregating in large numbers offshore on their way to spend the winter in tropical oceans. The nearest they breed to the UK is in Iceland and the east coast of Greenland. Phalaropes are also unusual in their breeding behaviour. Their breeding plumage is an attractive rusty-red although uncommonly among birds, the females have the more beautiful attire. This is because they perform the courtship displays as well as defend the territory. In this role-reversal, the males incubate the nest and look after the young as they are developing.

Grey Phalaropes pass through UK waters twice a year on their migration, although mostly keeping out of sight of dedicated sea-watchers on coastal headlands. This all changes, however, when events like those earlier this week occur.

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I was lucky to see this male Grey Phalarope in breeding plumage on the Svalbard Archipelago in Arctic Norway a few years ago.

On Wednesday, Storm Ali struck the UK, powering its way from the west with wind speeds in excess of 100mph. Less than two days later, Storm Bronagh also blew in from the Atlantic. The combination of these two systems had notable effects on sea-going birds, particularly Grey Phalaropes. Over the past few days they’ve been turning up all over the UK, including double-figure counts at locations in the South-West. Of this large number, around 60 were found at inland locations, one of which being Bough Beech Reservoir in Kent. This is only a half hour drive away from me, so I couldn’t resist the opportunity to see my first British phalarope.

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The Grey Phalarope at Bough Beech Reservoir. It has been aged as a first-winter, meaning that it hatched this year somewhere in the Arctic.

Sadly, as with any vagrant bird, it is likely that at least some of these displaced phalaropes will be unable to make it back to where they’re supposed to go. Storm-driven birds often use up a lot of energy on their wayward journeys and cannot find enough food where they end up. Furthermore, birds like these phalaropes have usually never seen humans before in their remote, high-latitude nesting grounds. Therefore, they are frequently confiding and approachable, putting themselves at huge risk. Fingers crossed that this one gets back on track!

 

The People’s Walk for Wildlife – my three hopes

It is fair to say that a better day could have been chosen weather-wise for today’s People’s Walk for Wildlife, although that didn’t stop thousands of people old and young making their voices heard in London. There were attendees from Northern Ireland, Scotland, Wales, the Channel Islands and even Uganda! This illustrates how much we care about the state of our environment and the unfathomable diversity of species it supports. Everyone at the walk today shared a common goal: to restore wildlife to the condition it was in before the disastrous effects of the Anthropocene. However, I have three hopes for the near future which I’d love to be fulfilled.

1. Large-scale rewilding

I’m lucky enough to be able to visit the Knepp Estate in West Sussex fairly regularly for bird ringing and general wildlife recording. It is one of several rewilding projects in the UK but the only one of its kind in the South-East, which is what makes it even more special.

The idea of rewilding involves restoring ecosystems to how they were in prehistoric times – before humans reaped such major consequences on the environment – mainly by reintroducing or replicating the megafauna which would have populated them. In less densely populated areas of the UK, there are plans and ambitions to reintroduce large carnivores such as lynx and wolves. However, in the South-East, there is simply not enough space for a thriving population of animals such as these. Yet, rewilding at Knepp has still had a noticeable effect on biodiversity without such iconic predators. On the estate, large herbivores/omnivores have been introduced to mimic those which would have been present in England many centuries ago. Free-roaming Tamworth pigs rootle in the undergrowth in the place of wild boar; longhorn cattle fill a niche which would previously have contained aurochs; Exmoor ponies replicate the benefits tarpan (Eurasian wild horses) would have had on the ecosystem.

It is evident that rewilding has already greatly benefitted Knepp’s wildlife. The pigs have produced bare ground ideal for nesting solitary bees. The tough cattle and ponies have prevented unique species-rich grassland and scrubland from reverting to woodland.

The idea came about at the start of the millennium when the lack of profit from the working farm the estate once was became a problem. Fields had to take up every scrap of available land and push wildlife to the edge in order to produce a good crop. Therefore, Charlie Burrell and his wife Isabella Tree (who has written a book on this subject entitled ‘Wilding’ – highly recommended as this blog post far from explains everything!) decided to think outside the box.

If rewilding can be so successful on a lowland farm surrounded by towns and less than forty miles from the centre of London, then it can surely also be implemented on farms nationwide. This would bring back biodiversity we have not experienced for many generations.

2. Putting nature back into childhood

The younger years are when lifelong interests are kindled. What’s experienced during childhood can spark a passion that can burn for decades. Long gone are the days when playing in the wilderness used to be the default for children, replaced by addictive screens. Without learning to love and appreciate even the wildlife on their doorstep, there is no chance that young people will be the driving force for conservation in the future. This is why it’s imperative to teach the next generation why our natural heritage is something that must be conserved.

3. Leave no species under-recorded

It is a simple truth that we cannot conserve a species if we don’t know its ecology, where it’s distributed or even if it exists. This is why recording the species we come across is so important for conservation. Even records one might consider as commonplace, such as a harlequin ladybird overwintering in the corner of your living room, can feed vital data to recording schemes. How far has this invasive ladybird spread? Which times of year is it most active? What consequences is the advent of this non-native having on our indigenous species? These are all questions that a few seconds spent uploading a record could answer.

There are many easy ways to submit records. Many recording schemes accept records from the Biological Records Centre’s iRecord website. Alternatively, you can email records directly to the relevant recording scheme or records centre. A list of recording schemes can be found here.

Daily, exciting new records are being made nationwide; a new species for a county, or even a country. Anyone can make a ground-breaking discovery just by sending in a record. There are tens of thousands of invertebrate species, thousands of fungi, thousands of plants, algae, lichens, mosses in the UK alone. Every one of them is equal, and requires conserving just as much as the iconic birds and mammals. Yet, there is no chance of preventing a planning application from destroying a site if there is no data on any scarce or declining species which might inhabit it. There is no possibility of stemming the invasion of a non-native species if we don’t know that it has arrived. There is no way of managing a habitat for a species if we don’t know which kind of habitat it prefers.

The catastrophic decline of biodiversity in this country and elsewhere in the world must be halted, and if possible reversed; our own futures depend on it. The simple tasks listed here would begin to help; but there is much much more to be done.