I spend a lot of time on the wonderful Fenns, Whixall and Bettisfield Moss NNR (National Nature Reserve), taking photos, carrying out surveys and collecting species records. People from all around the country visit Fenns and Whixall Moss NNR often to see some of the rare species such as White-faced Darter dragonflies, Large Heath Butterflies, Raft Spiders, Hobbies (falcons) or many other species found on what is now itself a very rare habitat, a lowland raised bog. This is the third biggest lowland raised bog in Britain. Those visiting the site for the first time are often awed by the sheer size and scale of the site.
My aim in starting this blog is to share what I see on my regular visits, alongside photos and other observations so people know what is around. As I say it can be an overwhelming experience when you visit the Moss for the first time, or even the first few times because of the sheer size of the site. Visitors often don’t know where to start looking for what they’ve come to see. I hope to help visitors to the Moss by sharing some of my knowledge about what can be found where. Those who’ve visited the Moss may likely have met me as I’ve helped many visitors find their first views of the various specialist species that they’ve visited Fenns and Whixall Moss NNR to see.
Above is a male White-faced Darter dragonfly Leucorrhinia dubia, one of Britain’s rarest dragonflies, and a species many visit Fenns and Whixall Moss NNR to see. Outside Scotland, where this species is not exactly common, there are only 3 main breeding sites left in England and Wales, and 2 further sites they’ve been recently re-introduced to. This species is on the wing from May to July.
Fenns and Whixall Moss NNR straddles the English Welsh border, being partly located in North Shropshire and Wrexham County Borough. Roughly 1/3 of the site is in England, and 2/3 in Wales, although the site is managed by Natural England with support from NRW (Natural Resources Wales). More information about Fenns and Whixall Moss NNR and how to get there can be found on the link below.
We had some hot sunny weather from Friday 19 April and I recorded the first Odonata of the year on this Good Friday, Large Red Damselflies Pyrrhosoma nymphula. This was on the Whixall, Shropshire, English side of the Moss. I believe they were recorded on butterfly transect C on the Fenns, Welsh side on Wednesday 17 April.
On Monday 22 April I saw 2 White-faced Darter Leucorrhinia dubia tenerals, and a single Four-spotted Chaser Libellula quadrimaculata dragonfly. These last 2 are very early, especially the White-faced Darters as it’s often May by time I record the first. Possibly a sign of climate change.
On Sunday 21 April I saw my first Green Hairstreak Callophrys rubi butterflies. There are moderate numbers of them in several locations, but it will take a couple of weeks before their numbers build up. It’s the same with Large Red Damselflies. As I write on 23 April I’ve found them at most locations I’d expect to see them, but there are only scattered individuals and are not yet in numbers.
Last year I wrote about Sitticus floricola, the nationally rare bog jumping spider being re–discovered on Fenns, Whixall and Mosses, only to have to amend the blog, because it turned out that the Sitticus species was S.caricis. In some ways this was a more significant find, because not only had it never been recorded on Fenns, Whixall and Bettisfield Mosses before, but it is the only record from the whole of mainland Wales, all of midland England and most of the north of England with the exception of an isolated single record in Cumbria. There is a record from somewhere between 1910-1915 near Lichfield, but how reliable this record is I don’t know. Otherwise the distribution of S.caricis is East Anglia, Southern England, and several sites on Anglesey, where Richard Gallon found it. Sitticus caricis discovered, not Sitticus floricola Re-disovered
On this Saturday 25 August, Richard Gallon, and Rich Burkmar of the Field Studies Council, BioLinks and now Cheshire county recorder for spiders, along with Andrew Allot set out to search for spiders. Partly to search one compartment to see if a second population of Sibianor larae could be found in the UK. Unfortunately it was not. My role was just to guide people around as my knowledge of spiders is limited, and the only discovery I made was to find an adult female Raft Spider Dolomedes fimbriatus with an egg sac. I didn’t get a photo as I kept sinking into the bog at the spot I found it. Sibianor larae a news species to the UK
However, Sitticus floricola was finally re-discovered at 3 different locations on Saturday 25 August. This was quite exciting because not only was it the first reliable records since I think 1988, but the first in these areas. Even more impressively, to my knowledge this makes Fenns and Whixall Moss the only site in the whole of Britain, where both species are known to occur on the same site.
In addition, other highlights were Heliophanus dampfi, the Bog Sun Jumping Spider, a first for Shropshire, and nearly a first for England if Rich Burkmar hadn’t discovered it at Holcroft Moss earlier this summer. Richard Gallon found Carorita limnaea, a very rare Money Spider on the Welsh side of the border, a first for Wales, which Richard was especially pleased about being the spider recorder for the whole of North Wales. I can’t provide a complete list yet, but overall it was a very successful day. Not least of all because this was the fifth search by Richard Gallon since last year for Sitticus floricola. I might provide an update on the full species list when available.
What this neatly illustrates is how on a huge site like Fenns, Whixall and Bettisfield Mosses NNR, that you can’t assume that just because a species is not found at a number of locations that it isn’t present. The Mosses may look superficially similar and homogenous across the whole area. However, there are lots of subtle differences in habitat type.
After the fourth summer of searching I finally got confirmation of the presence of Keeled Skimmers Orthetrum coerulescens, and a photo of this magnificent male. I can’t express just how elated I am. I’ve had a number of likely sightings in the last 4 summers, but on every occasion before I could get a photo or confirm the ID, they’d flown off across the Moss where I couldn’t follow. I was starting to doubt myself because each time I got close to a blue skimmer, or got a photo, it turned out to be a Black-tailed Skimmer Orthetrum cancellatum. The latter is a species I’m familiar and know to be present on the Moss on good numbers. Could I be getting it wrong, and what I was seeing were actually Black-tailed Skimmers? It didn’t seem like it because I’m familiar with Black-tailed Skimmer, but it’s difficult to be sure when you’ve only had a fleeting glimpse.
In Summer 2015, Sue Rees-Evans, then County Odonata Recorder for Shropshire asked me to look out for Keeled Skimmers on Fenns and Whixall Moss NNR, because she had a single record from 2013. When I checked the then NBN Gateway, now NBN Atlas, there were 2 other records from 2006 and 2007, but I couldn’t find any further information about these records. Apparently Sue had a photo of the 2013 record, a female if I remember rightly, so it should be a good record. However, there aren’t any other known sites nearby, and as far as I’m aware this is not a species which tends to wander much. In other words, there should be a population on the site if these other records were correct. Yet Whixall Moss is a very well visited and studied site, so you’d expect that plenty of other people should have seen and recorded them if there was a population on site.
In theory the site should be suitable for them. During the last 4 summers I’ve searched and checked out every skimmer I could. On a number of occasions I’ve seen what appeared to be an all blue skimmer with no black tail, and which looked to have the form of a Keeled Skimmer, but on each occasion when I’ve either gone to lift my binoculars up or my camera, before I could get it in focus it had flown over the Moss and I lost track of it.
Then whilst checking the area where the Keeled Skimmer was recorded in 2013 on Sunday 15 July, suddenly I saw a blue skimmer which looked like a Keeled Skimmer. Even better it caught a fly and landed to eat it. However, there was a Bracken frond in the way blowing around in the breeze, and which stopped my camera autofocusing on it. I tried to focus manually, but modern focus screens aren’t good for precise focus at a distance. So I got around the Bracken frond and managed to get 3 photos before it flew off.
The main difficulty viewing the skimmers on the Moss is that you can’t get close to the larger pools where you tend to see them, because these areas are boggy and treacherous. All you can be sure of is that you can see a blue skimmer. Only occasionally do they land on the paths, and when they do, if they take off, they always seem to fly off where you can’t follow them. This is why I suspect that even though there appears to be a population present, they don’t get seen or photographed very often.
Initially I was worried whether the view in the photo would be good enough for confirmation that it was a Keeled Skimmer, as I really wanted a shot showing the whole top of the dragonfly so you can see the thorax, and the top of it. Keeled Skimmers have light stripes on the top of the thorax, absent on Black-tailed Skimmers. However, I needn’t have worried as others immediately recognised it as a male Keeled Skimmer. Now, the aim is to get more photographic evidence of their presence.
On a side note, on the pools on the Smallholders Triangle, there remains a single male White-faced Darter. The previous weekend there had been four left, but on Monday 9 July there was only one left, and a dead one being devoured by water beetles. As of Sunday 15 July this male still remains. As you can see he has a damaged abdomen, where he was most probably grabbed by a bird. But this isn’t stopping him chasing away much larger male Common Hawkers.
Manchester Treble Bar moths Carsia sororiata, are a nationally scarce moth. They are more common and widespread in northern Scotland but have a far more patchy distribution in England and Wales. Their larval food plant is given as Bilberry, Cranberry and Cowberry. Fenns, Whixall and Bettisfield Mosses are a known site for this species and where they can be seen more reliably than other locations. Yet until this year I struggled to find more than just the odd one. I’m aware that with spotting the smaller scarcer moths, it’s all about getting your eye in, and knowing where to look.
I had a bit of a breakthrough in my understanding of this moth on Friday 6 July, which has enabled me to find this moth regularly. I thought I’d share this information, because I haven’t seen the behaviour I observed mentioned in any description of this species.
I’d managed to see a few of these moths when doing a UKBMS butterfly transect the day before, when it was oppressively hot. So hot that I had to give up on my search for them after finishing the transect walk because I was getting too hot. So I visited the Moss at sunrise, just before 5am the next day, mainly so I could search without being in danger of getting heatstroke. I was astounded at what I saw. Lots of Manchester Treble Bars and other moths including Purple-bordered Gold in flight. My guess at what species they were was confirmed, when occasionally they briefly landed. However, whilst it was possible to confirm the ID with binoculars, it was impossible to get photos as they only settled very briefly, before setting off again on their endless patrols. Presumably these were males searching for females, as their flight was almost non-stop.
This constant in flight and patrolling behaviour only lasted for about 1 1/2 hours at most after sunrise, then it rapidly dropped off in intensity, until no moths could be seen flying. The conditions were sunny and still. Only when they stopped their constant patrolling was it possible to find some Manchester Treble Bars at rest in the vegetation, where they could be photographed. Unfortunately this moth is very difficult to photograph, similar to Large Heath butterflies. It’s very skittish, taking off at the slightest disturbance, often flying some distance over boggy terrain, where you can’t follow them before settling. Likewise it often settles in the Purple Moor Grass Molinia caerulea, where it’s difficult to get a clear view of it because of other grass in the way. Also it hangs at odd angles making it difficult to get the focal plane of your camera to it so all the wings are in focus. In other words finding one in pristine condition, resting in a place easy to photograph it at the right angle, is time consuming.
Fortunately you can find individuals at rest in the vegetation lining the publicly accessible Mosses Trails. Finding them needs lots of patient searching. In flight they are light coloured, and have a grey look. However, there are large numbers of another light coloured moth, a grass moth, the Pearl-band Grass Veneer moth Catoptria margaritella. Whilst these moths look nothing like each at rest, in flight they are a similar size and can be confused. The grass moth looks whiter in flight, doesn’t fly or flutter around so much, and tends to quickly dive down in the vegetation again, when disturbed. The Manchester Treble Bar looks more greyish, and tends to have a more purposeful flight, often although not always flying some distance.
Overall, if you want to find the location of where Manchester Treble Bar moths are, you ideally need to look around at first light on a fine and still morning. You need to look around patches where there are large patches Sphagnum, and Cranberry. It should be noted that on the Moss the Cranberry beds are not the only places where Cranberry is found. In fact, whilst I’ve found Manchester Treble Bars in the Cranberry beds I’ve found more elsewhere. However, if you want to photograph them, and not just seem them, you will have to look in the vegetation at the edges of the path, later in the day, and familiarise yourself with what they look like in flight when they are flushed out of the vegetation.
Today I photographed a mating pair of Purple-bordered Gold moths Idaea muricata. They’re a nationally scarce moth, which don’t occur on many sites. To capture a mating pair was something I was really pleased with, and never hoped to witness, as I see very few mating pairs of moths, presumably because it takes part in the undergrowth, out of side. In fact, along with fellow NNR volunteer Barry Probin, we witnessed the whole courtship process. And a big thanks to Barry for acting as assistant with the photos i.e. removing bits of vegetation, and holding the grass stem in the breeze.
During the courtship 2 males appeared to fly around what appeared to be the female for some minutes, before one of them paired with what appeared to be the female.
It’s always been a bit of a puzzle about Purple-bordered Gold moths Idaea muricata on the Moss. All the British references say their larval food plant is Marsh Cinquefoil Comarum palustre, and yet there essentially isn’t any Marsh Cinquefoil on the Moss. So what do the larvae feed on? Even more puzzling is that on sites with plenty of March Cinquefoil, is that there are no Purple-bordered Gold moths.
I was discussing this last year, and came across this German reference, which claimed that the larval food plant was Cranberry Vaccinium oxycoccos, and other dwarf shrubs, as the larvae was polyphagous. This made sense because there is plenty of Cranberry on the Moss. Plus I’ve found quite a lot Puurple-bordered Gold. this year newly emerged in areas with lots of Cranberry.
Of course this doesn’t prove that Cranberry is their larval food plant, but it is a lot more plausible than it being Marsh Cinquefoil. This has to be confirmed by finding the eggs or larvae of the Moss on Cranberry.
PS. My apologies for not updating the blog regularly, and I hope to remedy this. Expect a big blog soon, and the latest news about species on the Moss.
This is an informational piece. Hobbies Falco subbuteo, typically arrive on the Moss around the end of April, just in time for the emergence of the dragonflies and damselflies. Quite large numbers can gather. Certainly it’s not unusual to be able to count numbers of Hobbies in the air in an area into the teens. It’s difficult to estimate the total numbers on the Moss as it’s a huge area, and likely all the Hobbies are not in the same area, or are even flying at the same. Plus they’re so fast, and travel so much ground in seconds, that as you turn your head to count others, you lose track of the ones you’ve already counted.
Typically you’ll see several together the first time they appear in late April, and then numbers will build up rapidly. The Moss seems to be a gathering point before they disperse to breed. This is the thing about these Hobby numbers, and that is they will only last until the dispersal to breed, which is somewhere from about the end of the third week of May onwards. I suspect the date isn’t fixed and it depends on weather conditions. Possibly this dispersal is triggered by there being enough food, as numbers of Odonata build up, and it means plenty of food to sustain the adults and feed the chicks when they hatch.
Generally around 1-2 pairs of adult Hobbies remain on the Moss, and maybe several non-breeding younger individuals. I don’t think these numbers are static, with possibly individuals arriving or moving on. However, once the dispersal to breed has happened it’s unusual to see more than about 3 individual Hobbies in the sky at one time, and usually you’ll just see 1-2 at a time.
For anyone hoping to get close photographs or just close views of either flying or perched Hobbies, it gets much harder after they have dispersed. With such a large area, and relatively few birds, the odds of you being in the spot where the Hobbies fly close or perch get much smaller. When there are lots of Hobbies there is much, much more chance that they’ll fly close to you, or perch nearby.
In August numbers of Hobbies will pick up again as the breeding is over and not only adults, but youngsters will appear. But numbers will generally never be as high as in early May, and individuals come and go. In addition, you’ll notice wing feathers missing on many of the adults.
Yesterday on Monday 21 May I sat out in the middle of the Moss near the weather station, which gives the overall best view over the Moss, and could only see at most 2-3 Hobbies. Mostly it was just the odd individual. Therefore I’m guessing that they’ve dispersed as it was a hot fairly still day earlier, with plenty of dragonflies about. Numbers seemed down on Saturday 19 May. It remains to be seen, but I think we’re now past peak Hobby time for this year. Numbers will rise again by mid-August when breeding is over, but it is difficult to predict how many will be on the Moss at any given time, until they leave in September.
I’m sorry for not updating the blog for some time. It’s been a strange old Winter and Spring. Firstly, as noted in my Winter Update it was unusually quiet on the Moss over the Winter, with there being much less roosting Fieldfares and Redwings on the Moss, and the virtual disappearance of Reed Buntings, Stonechats and Meadow Pipits on the open Moss (there were some Reed Buntings but only on the periphery of the Moss). This meant that quartering Hen Harriers and hunting Merlins were a rare site this Winter. Although a female Hen Harrier (Ringtail) did turned up for a couple of weeks in February.
I was longing for Spring, and thought come March everything will pick up. Unfortunately as everyone knows it’s turned out to be a strange Spring, with sudden periods of very cold weather “the beast from the east” and it’s subsequent lesser sibling later, followed by some record breaking hot weather. This meant the gradual awakening of Spring got interrupted several times, and everything was late and out of synch. I kept thinking once this or that happens, I will write a new blog entry only for it not to happen as expected.
The Reed Buntings, Meadow Pipits and Stonechats were suddenly in evidence on a cold and frosty (-5C), but sunny morning on 21 March. It was also the day the Curlews changed from their flocking behaviour on the fields surrounding the Moss, to take up their breeding territories out on the Moss.
The flooded fields were more flooded than last Winter and there were good numbers of ducks and geese, including more Wigeon the I remember in previous years. However, there’s been a curious lack of waders, even the after mud was exposed when water levels fell.
Swallows over the Moss and outside the surrounding farms were late, and numbers are still low. It appears that there’s only one male Cuckoo calling over all the Marches Mosses, which I will cover in another blog entry. It was first heard on 17 April.
The ducks and geese from the flooded fields have dispersed to breed, and many are nesting out on the Moss, including more Shovellers than I remember in previous years.
The first butterflies I saw were a few male Brimstones along the canal by the Quob in a brief warmer spell on 25 March
The first decent sized Raft Spider I saw on a pool was on 5 April. It must have been a hardy specimen because it was pretty cold at the time.
The first Large Red Damselfly I saw was on 21 April during the brief hot spell we had then. But this was a single individual. It then went very cool again, and so predictably nothing else emerged until the beginning of May. It seems to have been the first damselfly or dragonfly record for Shropshire in 2018.
My first Hobbies were seen on the 28 April, including this one, which I managed to get to within less than 15m (50 foot) from by carefully just taking one step at a time and pausing, as I do with my dragonfly approach method. I believe the first Hobbies seen by someone else were a day earlier than this.
Unfortunately the late emergence of damselflies and dragonflies have meant that the Hobbies have had nothing to feed on lower down. On the bird walk on 5 May, I promised everyone Hobbies, and whilst they were seen, they were very high. I think they were feeding on a large hatch of Mayflies being drawn up by the warmth of the unusually hot weather. Only once the damselflies and dragonflies mature and start flying low over the pools will the Hobbies really be putting on their incredible aerobatic displays.
My first sighting of a dragonfly proper was this teneral female White-faced Darter on 4 May. I’m not sure if there were any other sightings prior to this.
During the bird walk on 5 May I saw my first Four-spotted Chaser Dragonfly of the year, but didn’t get a photo until 6 May. It appears that there are no fully mature dragonflies or damselflies yet, because even during the very hot weather between 5-7 May, there was no dragonfly or damselfly activity except emergence around the pools.
Green Hairstreak butterflies have been emerging in more numbers since the warmer weather began on 4 May, but numbers are not high yet.
Wonderful male Emperor Moths have been winging around the Moss. Most of the time you just see an orange blur, and in flight they look a bit like a Small Tortoiseshell butterfly with an unusually fast wing beat. Only when they occasionally land will you see their full magnificence.