Roaming Rame

At about 10.30 on the 15th, a warm Cornish July day, I set off from my campsite in Maker near Torpoint to begin a short trek to Rame Head. Fuelled by a fried egg from the campsite barbecue (gulls had stolen our bread in the early hours) and a croissant from a bar in Cawsand, the uphill track to the headland felt like light work, doubtlessly aided by the promise of cirl buntings on the horizon.

Prime cirl bunting habitat at Rame Head, with the tiny Rame Head chapel isolated on the promontory

Cirl buntings are blessed with the dual qualities of being attractive and rather rare. The males, the flashier sex, are predominantly russet and greenish-grey, with darker longitudinal stripes on the mantle, a black throat, a bright yellow collar and a pair of yellow stripes running above and below the eye. The more subtle females lack any greenish-grey or black feathering but are mostly streaked with brown. Their voice is almost as distinctive as the plumage, with the name cirl bunting actually stemming from the Italian verb zirlare, meaning ‘to chirp’ or ‘to sing like a thrush’.

Walking along the coastal path towards the headland, it was this distinctive song which proved instrumental in finding these localised buntings. Arjun, who had visited the site previously, kindly sent coordinates for where they had been seen in the past, yet the sound of the buntings greeted me long before I reached that point. Without the birds being so vocal I imagine I would’ve had a rather hard time locating them, as the dense gorse and blackthorn provided a superfluity of places where a small songbird could hide. Yet their vocal advertisement of their location allowed me to creep closer and closer and eventually attain much better views than I could ever have hoped for, and make some recordings of their characteristic song, one of which you can listen to here: https://www.xeno-canto.org/663598

One of the many singing male cirl buntings

The sheer abundance of cirl buntings at this site is fantastic news for the species. Cirl buntings used to be widespread in farmland in southern England, yet the population fell to its lowest levels in the 1980s with only just over a hundred breeding pairs, confined to a handful of locations in south Devon. This collapse is mostly attributed to changes in how we farm, including the use of non-specific herbicides which killed the arable ‘weeds’ whose seeds provide the buntings’ main food source. However, since that sharp trough, conservation organisations such as the RSPB have overseen a strong resurgence in the species’ population thanks to the provision of funding to farmers to improve cirl bunting habitat on their land. Cirl buntings are now found along a sizeable stretch of the Devon coastline, as well as just over the Cornish border in Rame. We are still far from replicating the cirl bunting’s historic distribution across southern England, yet continued improvement to agricultural practices and reintroduction schemes (which have already shown success further west in Cornwall on the Roseland) mean we may not have long to wait.

My top 10 natural history highlights of 2020

It would be hackneyed to describe 2020 as a year like no other, although it certainly provided a fresh set of challenges which I had never had cause to experience before. However, through all of the disruption, this year cemented the fact that fascinating wildlife is wherever you look for it, even when you’re confined to your garden or local park.

  1. Long-eared Owl, Isle of Sheppey, Kent

My first wildlife highlight of the new year came on January 2nd, in a gravel car park on the Isle of Sheppey in Kent with Calum Mckellar. The aim of the trip was to get our birding year lists off to a good start (although for me at least, for obvious reasons, this did fall by the wayside as spring advanced). In that regard the foray was a great success, with Bearded Tits, Barnacle Geese, White-fronted Geese, a Tundra Bean Goose and my best ever views of the notoriously hard-to-see Long-eared Owl in its daytime roost.

Long-eared Owl, Isle of Sheppey

2. Entomobrya corticalis, Broad Oak, Sussex

2020 was a year full of springtail highlights. With such an under-recorded group, there is plenty of scope for some exciting and rare finds. During the first half of the year, these included the first Surrey records of Pogonognathellus flavescens and the undescribed species Jordanathrix nr. superba (the latter in my garden). My favourite, however, was the first Sussex record of the arboreal Entomobrya corticalis, while I should have been looking for mosses and liverworts at a bryophyte recording meeting!

Entomobrya corticalis, Broad Oak, Sussex

3. Rhinoceros Beetle (Sinodendron cylindricum), my garden

At the start of the year, I was gifted a pair of vane traps from the co-ordinator of the National Agromyzidae Recording Scheme (a family of leaf-mining flies). Vane traps are traps designed to intercept flying insects, allowing the recording of many species one would not normally encounter. One of the traps was deployed in my garden during the spring, summer and early autumn and, among many other fantastic invertebrates, caught not one but two Rhinoceros Beetles. Despite being one of Britain’s largest beetles and the evidence of them breeding in my garden, this was a completely new species for me!

Rhinoceros Beetle, my garden

4. Inostemma boscii, my garden

One of the more welcome challenges of 2020 was attempting to get to grips with the identification of parasitic wasps. To the naked eye, most chalcidoid wasps look like tiny, black, boring insects, yet under the microscope are intricately beautiful and interesting. Inostemma boscii was one such example: a <2mm wasp swept from long grass in my garden, the female of this species has a remarkable horn (cornutus) which it uses to store its long ovipositor, used by the wasp to lay eggs in the early stages of gall midges.

Inostemma boscii, my garden

5. Agrilus laticornis, Hedgecourt Lake, Surrey

A lot of my time in summer was spent on my local patch, Hedgecourt Lake. On one visit, on the shore of the lake (unusually), I found what I had been looking for for a long time, a jewel beetle. Despite being the most speciose of all animal genera, the genus Agrilus is not the easiest to find in the UK nor the easiest to identify, but I was able to put this find to good use and make a short identification video for British jewel beetles:

6. Orchesella flavescens, Hedgecourt Lake, Surrey

Agrilus laticornis was far from my only wildlife highlight from Hedgecourt during the year. Again, springtails are featuring in these highlights, with this find definitely in the running for my favourite of the year. Orchesella flavescens is a winning combination of beautiful, distinctive and very rare, not being seen in the UK between 1925 and 2009. To find it so very close to home was the icing on the cake. The other springtail highlights of the second half of the year were Surrey’s first Folsomia manolachei, the rarest Lepidocyrtus species (L. ruber), the first record of Ptenothrix atra from Sussex, swiftly followed by finding P. atra in my own garden, the second record for Surrey after the first in 1943.

Orchesella flavescens, Hedgecourt Lake, Surrey

7. Ponera coarctata, my neighbour’s garden

In August I was given the opportunity to conduct a wildlife survey in a neighbour’s garden in return for a donation to Reserva: The Youth Land Trust (http://www.reservaylt.org). The donation, in support of Reserva’s work to purchase a nature reserve in Ecuador’s Choc√≥ Rainforest using solely youth-raised funds, was not the only benefit of conducting the survey. I also uncovered a rare new ant species for me, Ponera coarctata, a very localised denizen of warm sites in southern Britain. This record complements other cryptic ants I found in my own garden this year: Lasius brunneus, an arboreal woodland species, Stenamma debile and Temnothorax nylanderi, tiny ants of leaf-litter.

Ponera coarctata, my neighbour’s garden.

8. An abundance of Ivy Bees (Colletes hederae), Pulborough Brooks RSPB, West Sussex

In contrast to just a few years ago, Ivy Bees are no longer a rare species but rather the opposite, which is what makes them such a spectacle. In September, Arjun Dutta, Samuel Levy and I joined Mya Bambrick on her charity walk at Pulborough Brooks RSPB, raising money for the Cameron Bespolka Trust (https://www.cameronbespolka.com/). Alongside some brilliant bird sightings, we also had the opportunity to immerse ourselves amongst hundreds of Ivy Bees busy foraging on a wall of ivy:

9. Caloptilia honoratella, West Runton, Norfolk

Over the course of the year I’ve been assisting a few young lepidopterists with my improving dissection skills, a necessary facet of moth identification in many cases, allowing accurate records of more obscure species to be made (known colloquially as gen. det., for genitalia determination). During 2020 I wasn’t able to visit Norfolk, and I’ve never been to West Runton. However, thanks to some specimens from Louis Parkerson, I was still able to contribute to our knowledge of the Norfolk moth fauna. One of these specimens transpired to be Caloptilia honoratella, the 7th British record and first record for Norfolk. This accompanies the first Coleophora orbitella for East Norfolk and the first records of Grapholita molesta, Oegoconia caradjai and Parornix carpinella for Berkshire, the latter three courtesy of Finley Hutchinson.

10. Rustic and Little Buntings, Thursley Common, Surrey

The final natural history highlight of 2020 is a two-in-one. Both Little Bunting (below, left) and Rustic Bunting (below, top right) are very scarce birds in the UK, and even more so in landlocked Surrey. Both buntings breed in the taiga of north-eastern Europe and northern Russia, a far cry from balmy Surrey. However, both species have been frequenting the same bush on Thursley Common since October, and are still in residence as I type. I was fortunate to see both buntings on a visit in mid-December, before Waverley was put into Tier 4. Since then, to further tantalise the birders unable to visit, a second Little Bunting has joined the flock!

It is clear that despite staying local during 2020, this has had little effect on the quality of the wildlife I’ve been able to see. In fact, building up a good picture of the wildlife present in your immediate area is perhaps even more important for biological recording and nature conservation. Going into 2021, I’ll be interested to see which other members of the local fauna I can uncover!

Dotards of Ditchling

The Eurasian dotterel is a bird which doesn’t seem so far removed from its close relatives upon first glance, yet a sortie into its ecology soon proves this to be untrue. Its appearance, particularly in the winter months, resembles a golden plover, although the dotterel is classified in the same genus as the ringed plovers. However, unlike the ringed plovers – and practically every other European plover – dotterel are very rarely found near water. Dotterel will breed in the summer months at the very top of mountains and plateaux, which in the UK means upland Scotland and a select few sites in northern England. So how did I manage to photograph the bird below at Ditchling Beacon, in south coast Sussex?

Eurasian dotterel, Ditchling Beacon, photographed with my phone through my telescope.

Apart from its unusual habitat choices, another interesting aspect of this species’ behaviour is its migration habits. In spring, and occasionally in autumn, this species will migrate in parties known as ‘trips’, which can number about 20-30 individuals nowadays. In both seasons another peculiar feature of their migration is that they regularly stop over at traditional sites, which many decades ago would draw hunters from far and wide. These traditional sites seem to be clustered further north but there are a handful in southern counties, with Ditchling Beacon occasionally hosting the bird. The ‘trips’ won’t always stay true to their traditional sites, with the first group of dotterel to be recorded in Surrey for 128 years appearing near Banstead in 2012.

On passage, the group of 3 dotterel I was fortunate enough to see last week had swapped the mountaintops of the Scottish Highlands for the stubble fields of Ditchling Beacon, with the English Channel just visible in the distance to the right of the image.

The word ‘dotterel’ was used in the 1400s for someone simple-minded or a dotard as well as for the bird, and it is unsure which word stemmed from which. The dotterel is so-called due to the ease with which one can approach them, making them easy targets for hunters in addition to their predictable movements. As you can see from the photo above, I was not willing to approach the Ditchling birds too closely in case they were disturbed. Birds on migration have enough trials to overcome without the added pressures of humans and dogs disturbing birds when they could be feeding and putting on weight for the next leg of their journey.

An identification composite from Crossley.

Third in the list of unusual details of dotterel ecology is their plumage. The three Ditchling birds were all either juveniles or winter-plumaged, so more dull than one would expect to see them on their breeding grounds. However, as the ID composite above shows, dotterel are very attractive birds in the summer months. As you might anticipate, the two birds in the foreground are adults in breeding plumage, although the sex of each might surprise you. The duller bird on the left is the male, while the more strikingly-plumaged individual on the right is the female.

The dotterel is one of the very few bird species in which the roles of either sex could be considered reversed, with the male incubating the eggs and taking care of the chicks, and therefore requiring more camouflaged feathering. The females on the other hand are polyandrous, producing several clutches with different males each season. This is rare in birds, with only a tiny fraction of species exhibiting this behaviour, mostly shorebirds such as phalaropes and jacanas. Polygyny, the male equivalent, is much more frequent, occurring in 8% of bird species, such as birds-of-paradise and grouse, in comparison to the 0.4% of bird species which are polyandrous. Polygynandry is the rarest mating system, where both the males and females are promiscuous. There may be several reasons why these behaviours are practised, but in polyandrous species the clutch success rate is often lower. As a result, it is more beneficial for the female to have her progeny guarded by multiple males in the hope that at least one of them is a competent father.

As you can see, the dotterel is a fascinating bird, much more so than one would have assumed from my photo above. I hope that trips of dotterel will long be stopping off at their regular haunts for many migration cycles to come, and I hope that soon I’ll have the chance to see their unusual breeding behaviour first hand.

Flavescent: ‘the most magnificent springtail’

Having lived within 15 minutes’ walk of Hedgecourt Nature Reserve for my entire life and visiting it on a weekly basis during the holidays, one would be forgiven for thinking that I would have a fairly good grasp of the fauna and flora living on the site. Furthermore, having focused a lot of my effort on springtails over the past few years, that fact might be especially true for these small denizens of leaf-litter, soil and tree trunks. And, trying not to sound excessively dramatic, the afternoon of July 10 was not unlike any other. That was, until I found the holy grail of south Surrey woodland sexpartite-antennal entomobryid collembology.

The genus Orchesella is distinguished from all other British Collembola (springtails) by having the antennae divided into six segments (usually), which are of differing lengths. They’re fairly large as springtails go, with the largest reaching over 5mm in length. They’re also distinctively patterned, making them among my favourite genera, although before this month, I’d only recorded the two common species: Orchesella villosa and O. cincta. Six other taxa have been previously recorded in the UK, however of those only O. alticola (a montane species) and O. flavescens have had confirmed records – with the others either unconfirmed or referring to colour variations of O. villosa.

The scarcity of Orchesella flavescens can be highlighted by the fact that there were no reliable records of this species anywhere in the country between the years of 1925 and 2009, when a population was discovered in north Sussex, near Gatwick. Since then, a few other populations have been discovered in southern England, including one in Surrey. Given the relative proximity and similarity of these sites to the woodland habitats around me, I knew I was in with a chance of running into this species, although I would have to be very lucky. The appeal of Orchesella flavescens is amplified by the description of the taxon by the eminent recorder H. Womersley in The apterygotan fauna of the south west of England, published in the Proceedings of the Bristol Naturalists Society in 1924:

This, in my opinion, the most magnificent spring-tail, was again taken in its previously recorded habitat amongst dog’s mercury at Flax Bourton Combe, Som., May 17th, 1924.

Hence, I think that you can imagine my joy upon discovering a juvenile in my sweep-net on the afternoon of the 10th! Unusually for a springtail, it is instantly recognisable in the field without any magnification. While O. cincta has the third abdominal segment completely dark-pigmented and O. villosa has intricate and discontinuous patches of dark pigment across its body, O. flavescens has the pigment arranged in neat longitudinal lines.

Orchesella flavescens

I must confess that the photo above is not of the specimen I found on the 10th. However, it is even more exciting, for during a repeat visit on the 22nd, two further examples of O. flavescens were discovered, including this one! Considering that I’d spent many years visiting Hedgecourt without a hint that O. flavescens might be present there, to find the species on two occasions within the space of a fortnight is remarkable.

Another point of interest about the above image is the form of the antennae. A curious fact about Orchesella is that the antennae are often asymmetric – and this specimen of O. flavescens is a clear example of that. The antenna on the left has six segments (the basal segment is very small) whilst the one on the right has five. This lack or shortening of segments can occasionally be seen in other species where the antennae have been damaged, but as for why it occurs more frequently in Orchesella is unbeknownst to me.

The takeaway from this fantastic record of a seemingly scarce and good-looking springtail is that it is very unlikely that O. flavescens disappeared from the UK for over 80 years between 1925 and 2009. The populations we are discovering at the moment have likely been in situ for many years, and there are undoubtedly more awaiting discovery. This exemplifies the importance of better recording coverage of this taxonomic group which is often ignored by many naturalists. O. flavescens is the perfect springtail for even the casual naturalist to be on the lookout for: a large, distinctive species with no microscope required!

The roost and the goose

The second day of the decade dawned dull and dismal, as Calum and I headed towards the Isle of Sheppey. After a decent circuit of Oare Marshes with species such as Rock Pipits, Bearded Tits, four fly-over Barnacle Geese, and a multitude of Cetti’s Warblers, Brents and waders, the time had come for us to cross the tidal channel of the Swale to try to find our first particularly special bird of the day. Fortunately for us, the weather did not reflect the quality of the birding!

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Drake Pintail.

Driving the entrance track of Elmley NNR felt a bit like a game drive in the heart of Africa, except with stubborn cattle replacing the bush’s big five. Across the flat expanse of wet marshland, hundreds of lapwings abounded and the distant cackle of wildfowl foreshadowed things to come. Eventually, once the unphased and unimpressed cows had moved off the road, we came to the car park of the nature reserve. And this car park was how all car parks should be: we barely had to walk twenty metres from the car before we locked eyes with an enchanting Long-eared Owl.

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Roosting Long-eared Owl.

This was the first time I’d been able to photograph this elusive owl. Long-eared Owls are very patchy and localised in their distribution, although the breeding population is boosted by non-breeders in the winter months. However, it is possible that these owls are becoming less frequent as winter visitors on account of climate change: the increasing mildness of the continent means that they are less willing to cross the North Sea in search of warmer climes. The warming climate of northern Europe is reducing the need to spend the winter in the UK. However, ringing recoveries still show that movements from as far as Russia are still frequent.

Reluctantly, we left the Long-eared Owl to roost in peace without any prying eyes and headed down the track onto the wetlands between the owl’s scrub and the estuary. This led us towards a surprise flock of White-fronted Geese, one of the special geese which winter this far south in the UK. There are two races of the White-fronted Goose, with both wintering in the UK. The Greenland White-fronted Goose (flavirostris) has a long, orange bill and is typically less widely observed than the race we came across at Elmley, the Eurasian (or Russian) White-fronted Goose (albifrons), which has a shorter, pinkish bill. The adults of both races can be recognised by the black barring on the breast and the nominal white foreheads. However, juveniles can resemble the much more common Greylag Goose, as we found out when we laid eyes on a lone young White-front the next day at Rainham Marshes – a rarity for the reserve.

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A young White-fronted Goose at Rainham Marshes on the 3rd, showing the small size and pink bill, but lack of breast barring and white forehead.

I would be pleased if I came across the White-fronted Goose more than once over the course of a year. However, Rainham Marshes turned out to be our third site for this species, as our next stop after Elmley was the wildfowl-rich Swale NNR. The quality of the site, or perhaps less positively the lack of good habitat elsewhere, was reflected by the numbers of geese on the reserve despite the constant sound of gunshots reverberating from the surrounding fields. The realisation that there were two hunters with accompanying golden retrievers concealed in the saltmarsh behind us was somewhat disconcerting. Despite the obvious disturbance that the hunting causes to the whole wildfowl population of the reserve – the Brent Geese were constantly alert and would fly at almost every gunshot – the shooting of geese and waders is allowed to continue regularly.

As well as the Brents, Greylags and Canada Geese which are present on the reserve, the Swale NNR also supports a good-sized flock of White-fronts, with a few Tundra Bean Geese also visiting every winter. The risk of one of these rarer geese being taken out by a rifle is ever-present. Fortunately, on this occasion this year’s wintering Tundra Bean Goose was still feeding with a flock of White-fronts when we arrived as the sun was beginning to set. Hunters threatening the survival of rare geese on a more than weekly basis even at one of the remotest sites in the south-east is just one example of the perpetual human-induced risk experienced by the world’s declining biodiversity.

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With further unnecessary and avoidable pressure on already threatened goose populations, how long will it be before wildfowl flocks such as these Brent Geese begin to dwindle and disappear?

Brighton blues

With our changing climate, distributions and abundances of a wide range of invertebrates are ever-changing. In this regard, the headline butterfly event of the year was the record-breaking influx of long-tailed blues, reaching the British coast from their regular haunts of southern Europe. At the moment, in September, the offspring of the first wave of primary migrants are emerging from the broad-leaved everlasting-pea plants on which the females had laid their eggs in late August, allowing keen lepidopterists another chance to see this elusive species. However, I did not need this second chance – I was fortunate enough to lay eyes on some of this year’s earliest arrivals.

Walking up Whitehawk Hill on the late summer day of 29th August felt typical, 20 degrees yet with a fresh breeze blowing up from the Channel. However, what I was about to witness was an indication of our warming planet.

Upon reaching the top of the hill, I immediately saw two small butterflies spiralling frantically upwards against the expanse of Brighton in the background. I knew exactly what they were – territorial male long-tailed blues. These were small, dainty yet tireless butterflies, which had crossed the Channel and much of Western Europe to gambol between the community allotments and the scrubby border of the local nature reserve in the shade of the transmission tower.

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During brief interludes between the combat, these two males and a further individual occasionally paused on ground vegetation, allowing photo opportunities and examination of the species’ beautiful intricacies. The long-tailed blue is so-called on account of the two ‘tails’ which project backwards from the hindwing. These mimic the antennae of the butterfly, and coupled with the eye-spots on both the upper and lower surfaces, the tactic is to make predators attack this end of the insect, thinking it is the head. This protects the actual head from any damage from hungry insectivores.

The photo below shows one of the more worn-looking blues. There are chunks missing from the left hindwing where the eye-spot usually is, suggesting a predator mistakenly attacked the rear end of the butterfly, fooled by the fake antennae. This left only superficial damage to the butterfly.

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I did not expect finding these long-tailed blues to be quite so easy, and in the past it certainly wouldn’t have been. The first British record of this species was from Brighton all the way back in 1859 (leading to one of its earlier vernacular names being the Brighton argus), although in the succeeding 80 years it had only been sighted again 36 times. The number of sightings more than doubled between 1940 and 1988, with a large proportion of these being during an influx in 1945. However, it took until 2013 and 2015 before the long-tailed blue numbers really became significant, when relatively major immigrations took place into the southern counties. Already it is looking likely that the 2019 influx will surpass all previous influxes.

But why are these long-tailed blues making an effort to reach our shores? There are many other butterfly species which have similar distributions to the long-tailed blue in southern Europe, although they have made no attempt to colonise the UK. However, the long-tailed blue is not only found around the Mediterranean – one of the world’s most successful butterfly species, its distribution also stretches right down to Australia. For such a small lepidopteran, its flight is powerful and determined, showing no reluctance to cross seas and mountain ranges such as the Channel and the Pyrenees. Furthermore, the long-tailed blue is renowned for its ability to pass through its entire life-cycle incredibly quickly. Despite most primary migrants only appearing in the UK in late August, their offspring already started to emerge as adults in mid-September. This allows the long-tailed blue to gain a foothold on new lands with great speed, which gives this species a huge advantage in the face of increasing temperatures in the long-tailed blue’s ancestral homelands. Although the current year-round climate of the UK is too cold for the species to overwinter, it is quite possible that it won’t be long before it is resident in the UK and there will be more chances to admire this resolute butterfly.

 

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¬†Vespula 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!

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.

Apples on sticks

Yesterday the south-east group of the British Bryological Society visited the town of Wadhurst in the far east of Sussex, near Tunbridge Wells. A variety of habitats including streams, woodland, grassland and ditches led to an array of moss and liverwort species being recorded. All were new for the area as this was a place no bryologist had dared to tread before.

Highlights included my favourite liverwort, the large and fragrant Conocephalum conicum (Great Scented Liverwort), as well as non-bryophytes such as two new plant species for me ‚Äď Orpine and Soft Shield Fern ‚Äď and a new carabid in the form of Carabus monilis with its bronze lustre. However, apparently the best find of the day was one of mine. This was the apple-moss, Bartramia pomiformis.

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Bartramia pomiformis

This moss immediately struck me, growing on a sandy bank on the edge of a narrow lane. The patch was almost perfectly circular, a richer green than the surrounding winter vegetation. And it was easy to see how it got its name, from the rounded apple-like capsules.

These capsules, that many mosses have in some form or another, form the final stage in the life cycle of a moss. The capsules contain the spores. Like a fruit, the capsules darken with maturity, starting off green such as these but soon becoming dry and brown with age, at which point the spores will be released.

These spores, upon germination, will then grow into a protonema, which will develop into a sheet of felt-like rhizoids, from which the gametophore will arise. The gametophore will be the stage of a moss that many people will be familiar with. It is the typical plant-like form, with stems and leaves, resembling a flowering plant although without vascular structure. This means that mosses lack the transport systems that vascular plants use to transport water, nutrients and minerals to their cells through tubes such as the xylem and the phloem.

Mosses can be dioicous or monoicous. Dioicous mosses have the male and female reproductive organs on different individual gametophores, while monoicous mosses have both sex organs on the same plant. In both cases, the sperm from the male sex organ will be transported to the female sex organ by a drop of water, which is one reason why there is a higher density of moss species in wetter climates such as the Atlantic rainforests of western Scotland and Ireland.

Once fertilisation takes place, a sporophyte begins to emerge from the venter, where the embryo develops. Over a period of many months, a seta (stalk) will grow, on top of which a capsule will be produced. Eventually this will release spores, and the cycle will repeat itself.

When diving into the life cycles of many taxonomic groups, I am often amazed by the complexity behind what appear to be fairly simple organisms at a cursory glance.

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.