Bats in the Moat

This week we attended a bat evening at Fort Burgoyne. As our country’s closest point to Continental Europe, Dover has more than its fair share of castles and forts and I get a bit confused between them all, but Fort Burgoyne is positioned behind Dover Castle to protect it from a land-based attack.

Across the parade ground at Fort Burgoyne

Fort Burgoyne is one of the Palmerston Forts, built in the 1860s following concerns about the strength of the French navy. There was much debate in Parliament as to whether the cost could be justified, but Lord Palmerston, who was Prime Minister at the time, strongly promoted the idea. He was concerned that the French could land elsewhere along the coast and attack Dover Castle from the rear.

A Second World War blast wall obscures much of the frontage of the fort
The extensive buildings are now disused and generally in a poor state but have become an important swarming and over-wintering site for bats

In 2014 The Land Trust acquired the fort and hopes to manage it for the benefit of the community by running events and training sessions and also leasing sections out to local businesses. The band of enthusiastic staff members include a ranger who monitors and encourages wildlife – on the last inspection of his twenty-eight reptile sampling squares on the site, he found ninety-nine slow worms.

Our bat evening started with a talk on bat ecology in the stables and we then descended into the depths of the fort with torches to be shown some of the nooks and crevices where bats return every year to overwinter. Then, as it started to get dark, we walked down into the moat with bat detectors:

Dropping down into the moat at heavy dusk

The group had been lent a selection of different detectors with the most basic ones starting at a cost of around £100 and the most sophisticated at £1,600. We had brought along our own Magenta detector and were pleased to see that this was the one being recommended as the best entry-level detector.

There are eighteen species of bat in the UK, which is actually nearly a quarter of all British mammal species. Their echo-locating calls are pitched at different frequencies and can be used to identify the species even if you can’t see the bat.

On this basic Magenta detector, you dial up the frequency of the bat you think might be around and the device converts its calls into frequencies that we humans can hear. Standing in the moat, overhung with trees, and looking up at the rapidly darkening skies we set our detectors to 45kHz and we could see and hear common pipistrelles erratically flying around us, which was really quite a magical experience.

The downside of these cheaper detectors is that, if there are other species of bats around, you won’t hear them unless you are tuned in to their frequency. The more expensive detectors scan all the possible wavelengths and report on any calls, whatever the frequency.

A common pipistrelle in the hand. Photo credit: Drahkrub on Wikimedia Commons

Back in the meadows, the reptile ecologist continues to make monitoring visits after a hundred and four of these legless lizards were relocated here a few years ago. This is his photo of the sight that met him under one of our sampling squares this week – he was very pleased:

I looked under the same square the next day and they were all still there and I’ve included my photo as well because, although the light is less good, the animal on the right is in the process of shedding its skin which is interesting:

It’s a bit difficult to count, but possibly around seven to nine of them here

It is a glorious buttercup time in the meadows:

Fox with rabbit amongst the buttercups

Another rabbit – I assume it is being carried back to cubs, since this fox shows signs of lactating. We haven’t seen a fox cub in the meadows yet this year:

This same fox with that fur loss at the base of her tail is on the left here at peanut time as well:

The One-eyed Vixen and her mate, long-standing residents here, have had a worryingly bad dose of mange over the winter and, under the advice of The Fox Project charity, I have treated them with both Arsen Sulphur and then with Psorinum when that didn’t appear to have worked. I am relieved to see that now ginger fur is growing back on her flanks:

The One-eyed Vixen. I have lost count of the number of times I have treated this fox for mange – four or five I think
And her mate with his characteristically crooked tail, currently devoid of fur

The only fledglings that have been seen on the cameras so far this spring are magpies, but they are making up for that by appearing on as many cameras as they can:

Both rabbits and magpies love this trunk:

Although it seems to have stopped raining for now and the sun has come out, the weather has remained quite cold and windy here on the coast. Butterfly numbers are still low but we are enjoying seeing green hairstreak, speckled wood, small heath and wall fluttering around the meadows at the moment:

We have also spotted these day-flying moths:

Least black arches
Nematopogon sp. I don’t yet know why these longhorn moths have developed such ridiculous antennae. It makes it so difficult for them to fly in breezy weather
The cucumber green orb spider, Araniella sp, doesn’t hide because it relies on its colour for camouflage as it tries to catch flying insects in the small web that it strings between leaves. Although it had got its colour matching slightly wrong here, it had nevertheless caught a fly by the next time we looked

After weeks of speculation and increasing excitement, the tawny owl box in the wood has been opened by the licensed bird ringers and found to be empty. This was disappointing:

Since there had been so many photos of an owl in this box, we now think that it was the male roosting up in there while the female and chicks are elsewhere

While they were in the wood, they also looked in a second tawny box that we have up – a box that I have not had a camera on:

This one contained a nest full of baby great tits. With an entrance hole that large, how will they possibly survive predation by squirrels or woodpeckers?

We have just carried out the May tour round the dormouse boxes as the wood heads into its second year in the National Dormouse Monitoring Programme. As expected at this time of year, a lot of the boxes were occupied by nesting blue tits:

Very young chicks
And slightly older ones

Four of the thirty boxes in our section of the wood had dormice in them. The animals are weighed, sexed and aged before carefully returning them to their box.

A dormouse in his weighing bag
Two of the boxes had pairs of dormice in them and we are hoping for young next month

Green woodpeckers no longer seem to be using the hole in the cherry tree that I have a camera on and I suspect that there has been conflict with squirrels. The camera did get this action shot of a buzzard though:

A sparrowhawk wades put onto the new pond:

John the bird ringer wanted to photograph bullfinch and set up his hide next to one of the ponds in the wood that bullfinch have regularly been visiting:

I have a trail camera on this pond and so can confirm that the bullfinch immediately stopped visiting once the hide went up – and the hide was there for several days to give the birds a chance to acclimatise. John did, however, get some other nice photos of jay, chiffchaff, green woodpecker and robin whilst he patiently, but fruitlessly, awaited his target bird:

He has also been deploying his hide at a nearby old orchard, and I finish today with some photos of turtle dove and mandarin duck that he has taken there:

Neither of these species yet grace the bird list of the meadows or of the wood but I haven’t lost hope.

A Return to Elmley

Elmley Marshes is a 3,300 acre privately-owned nature reserve on the Isle of Sheppey, lying in the Thames Estuary and separated from the North Kent coast by The Swale tidal channel.

A NASA photo of the Isle of Sheppey from space. Elmley is the big green area in the bottom left of the island

On two particularly tempestuous nights back in January, we stayed in a shepherds hut in the middle of the marshes and loved being surrounded by all that nature. Over the winter sheep graze the reserve and large flocks of overwintering waterfowl were rising up from the marsh, their atmospheric calling filling the air.

We really wanted to see what this wonderful sanctuary was like in springtime and returned this week to continue our total-immersion nature therapy there.

Kingshill Farmhouse in the spring. Most of the marsh is very low lying and protected from the ingress of saltwater by a seawall. Kingshill Farm and the shepherds huts sit on a low hill, formerly an island when the marsh was tidal.
We stayed in the same hut as last time – the Salt Box now has a shiny new addition to its facilities – an eye-catching copper bath and outdoor shower
The view from the large and comfortable bed was very different at this time of year – in January this view had been filled with birds but now was strangely quiet. The over-wintering waterfowl are all gone and breeding birds are scattered secretively across the wet grazing land, busy raising their young

The management of the marsh is geared towards breeding lapwing and redshank. Getting the right balance of water levels, grazing of the marsh to produce the correct height and density of the sward and the controlling of predators are vital – but the weather is always an additional wildcard.

At this time of year, it is cattle rather than sheep that are on the marsh. The two bridges across onto Sheppey are seen in this photo – the high arching bridge is more prominent but it is the older combined road and railway bridge, with its two concrete croquet hoops that can lift the central section, that brings you to the reserve

As we drove along the two-mile track through the marshes and up to the farmhouse, using our car as a mobile hide, we were aware of lapwing and redshank in the wet grazing meadows on either side. A marsh harrier quartering low overhead brought out squadrons of previously unseen lapwing parents from all directions, anxious to drive the raptor away from their eggs and young.

Lapwing are such striking-looking, wonderful birds but their numbers have more than halved since the late 60s:

Redshank have suffered a similar decline:

Redshank chicks were wandering over the track but this was the best photo we got:

In the summer of 2018, 336 pairs of lapwing produced 429 chicks on the reserve and around 500 redshank were counted.

Predator control is an important part of encouraging these ground-nesting birds. There are no badgers on Sheppey anyway and a predator fence, closed from dusk to dawn, keeps foxes out of the reserve. Any foxes that do find their way in are shot, I’m afraid, and stoat and corvid numbers are also managed. Hedgehogs, voracious consumers of eggs, are live-trapped and moved elsewhere.

It is not just the birds that are benefiting from these low predator densities – hares, for instance, are also thriving there. Mother hares often park their young up by the shepherds huts where close human proximity acts as a further deterrent to any would-be predator such as a marsh harrier or buzzard.

A leveret, photographed through the hut window:

The dark eyes and shorter, paler ears of a rabbit, for the sake of comparison:

When we were in and around the shepherds hut, we also felt like we were running a creche for moorhen chicks. I became very fond of them all:

Our group of moorhen chicks were always interested to find out if we had any food for them
Will it grow into these feet?

They were also still being delicately fed by their parents:

There are a few chickens around the farmhouse, all named after members of Wham, and I would like to introduce you to George:

George is a very odd-looking Polish breed of chicken and she is a real character, wanting to be involved in everything and adored by all members of staff there

One afternoon we walked down to the bird hides and on the way I was most excited to see a black oil beetle lumbering herself across the path in front of us:

Black oil beetle, Meloe proscarabaeus. Oil beetles have a very interesting lifecycle that involves the larvae waiting in flowers for solitary bees to visit, grabbing hold of their fur and being carried back to their nest where they develop into adults at the expense of the bees

The Wellmarsh hide had good views of a noisy black-headed gull colony:

There were a few terns nesting in amongst the gulls and their nests were much less grand affairs. This common tern is landing back down onto her nest.

The gulls also have to share their space with ducks:

Here are two green-headed male ducks, the shoveler on the left and the mallard. I had never before noticed that the shoveler also has a blue patch on his side, although a much paler shade of blue than that on the mallard:

One black-headed gull had made the decision to nest on her own on a tiny island. I worry for her chicks that are going to be terribly exposed and vulnerable when they hatch:

The chicks on the two main gull islands have vegetation to retreat into if the need arises, which surely makes them more likely to survive. I like their spotty heads:

We loved seeing so many hares as we walked around the reserve:

A mother mallard watches over her brood:

There were not yet many butterflies about but I always admire an orange-tip:

We went out for an evening tour with the reserve’s wildlife guide and found a newly arrived hobby. This bird will have migrated here along with the swifts, catching and eating them as a moveable larder as they all flew northwards together.

Although there were swifts swooping over the reserve, this hobby will now be more interested in eating dragonflies that are just starting to emerge.

Here is the same hobby with its very stripy chest and red trousers, as seen on a mobile phone attached to a birding scope

The guide also took us to see a pair of barn owls nesting in a box. We were quite a distance away but saw the female coming in with a young bunny or hare for her chicks:

She also showed us two different little owl boxes, both of which are being used this spring. But, despite our best efforts, we didn’t see a little owl that evening. One of the boxes is on this ruined school, dating back to a time when there was a small cement works on the island:

The atmospheric school house ruins
The little owl box is at the back of the building

Jackdaws also nest in the school house and are apparently often observed pushing the owls’ buttons:

We returned to the schoolhouse the next morning and were disappointed to still see no owl. But when we visited a third time that evening, two shelduck were perched on the building as we approached. Before we could properly get our act together, a brown bird flew at the ducks – we had at last found our owl:

Once it had chased away the shelduck, the owl sat amongst the masonry. The light was not good for photography but the owl is to the left of what would have been the apex of the wall:

Spot the little owl

The next morning we walked to the school one last time before getting in the car to come home. This time the sun was shining on the building and onto the owl:

It felt like a grand finale of a fantastic short break away. But what of that new shiny copper bath? Had we put it through its paces? Well, yes, one of us did:

Personally, I felt much more comfortable showering inside the hut. We are now hoping to return to Elmley in the autumn for our third visit of the year.

Up to Down House

Down House in Kent, where Charles Darwin and his family lived for forty years, is now in the custodianship of English Heritage. On the right of the house is the old mulberry tree that stood outside the nursery in Darwins day and is still standing now

Darwin and his wife Emma moved to Down House in 1842 when Emma was pregnant with their third child. Charles had not married until he was thirty because much of his twenties had been spent exploring the World on HMS Beagle.

As well as the mulberry, many other old trees on the estate have been around since Darwin’s time
Using 19th century photographs, the layout of the garden has been returned to how it was then

The Darwins went on to have ten children, seven of which lived to adulthood and the family had been there for forty years by the time of Charles’ death in 1882. He had come up with his theory of natural selection when he lived in London before moving to Down House and, once in Kent, he set about testing this theory by observing and performing experiments on many different things. He spent eight years studying barnacles as well as earthworms, carnivorous plants, orchids, fancy pigeons and much else. He was very apprehensive about how his ideas would be received by a Christian society who, up until then, had thought that everything had been created at the same time by God. So he delayed twenty years before finally publishing ‘On the Origin of Species by Means of Natural Selection’ in 1859.

I love the anecdote that when one of Darwin’s sons went to play with a friend and was shown round this friend’s house, he asked “but where does your father do his barnacles?”

Charles Darwin’s study

It had been nearly twenty years since we last visited Down House but we had remembered Charles’ Thinking Path – in fact we had it in mind as we established our own well-worn circuit around the meadows. He used to make five circuits of his thinking path every day for exercise and headspace and, so that he didn’t lose count, marked each completed round by kicking a stone across from one pile to another.

Charles Darwin’s Thinking Path

As we walked in Charles’ esteemed footsteps around the path, we were delighted to spot several largish patches of toothwort, Lathraea squamaria, a parasitic plant that lacks chlorophyll of its own but which obtains its nutrients from the roots of other plants – mostly hazel and elm.

Named because it is supposed to resemble molar teeth, we have long wanted to see this rare treasure of a plant.

In Darwin’s 1862 book on orchids, he said that the green winged orchid was abundant around Down House and was a conspicuous feature of the vegetation. Unfortunately this orchid is now totally extinct in the area but an admirable reintroduction programme has been underway here since 2019.

Green-winged orchids growing protected by chicken wire as part of the reintroduction programme

We were captivated by the collection of special plants in Charles’ greenhouse:

A collection of carnivorous plants
A carnivorous Drosera species, related to our native sundews, with all that stickiness on its stems to catch flies
Tiers of different orchids

We had a lovely day at Down House. It was the start of the coronation weekend and the English Heritage cafe had the official coronation quiche on the menu. With its delicate flavours of tarragon, spinach and broad beans (the chef’s tip was to be sure to remove the skin from the beans before adding to the quiche) we liked it very much – I plan to try to produce it myself soon.

Coronation quiches at the cafe

Returning to the meadows, there are noticeably more rabbits around this year. We are pleased because the resulting small patches of short-cropped grass and collections of bunny balls create additional habitats for other things such invertebrates requiring higher temperatures at ground level and dung beetles.

The number of rabbit droppings on this trunk tells the story that rabbits like look-out points to watch for predators.

And talking of predators:

The One-eyed Vixen and her mate continue to both have mange and it doesn’t seem to be getting any worse but also isn’t getting better. I have sought advice from the charity The Fox Project and they advise to just wait and see for now.

I love this pair of photographs. The One-eyed Vixen’s mate approaches another fox in the gathering dusk:

And then this happens:

The pair of mallards are still visiting the pond every day but only briefly and just before it gets dark. Presumably the eggs have not yet hatched but it can’t be long now:

Herring Gulls are also nesting somewhere close by although thankfully not on the house:

And the starlings have at last arrived to start to nest. There are eight birds here and four pairs is about normal I think:

We have seen the first baby bird of the year for the meadows, and this year it’s a magpie:

The butterflies are so late this year. We would normally expect to see green hairstreaks from around 20th April but we have just seen the first one of the year on 4th May:

A blue helops beetle, Helops caeruleus, with its lovely blue-black sheen. It is a large, flightless and nocturnal species found near the coast usually in rotting wood, although we found this one deep within a roll of pond liner:

I wonder if it’s going to be a good year for St Marks flies, Bibio marci? Sometimes there are clouds of these billowing around the hedgerows, flying with characteristically dangling legs, but they were very low key indeed last year:

These mating snails are brown-lipped snails, Cepaea nemoralis. A common species, they come in a variety of colour forms but usually have that dark brown band around the shell opening. Although these snails are hermaphrodite, having both male and female organs, they need to mate in order to get sperm for each snail to fertilise its own eggs. Interesting!

Over in the wood, I found this exciting little thing in the marjoram clearing:

This is a glow-worm larva.

Glow-worms are beetles rather than worms and this larva is a predator, feeding on slugs and snails. The adults are only around for a short while in late June and early July and, while the male looks much like a standard beetle, the female is not dissimilar to this larva. At night in warm, still weather when there is little moon she will climb up a plant stem and the end of her abdomen will emit a greeny-orange light to attract a mate. This is something I have always wanted to see but never have – but I will definitely be trying to put that right this summer.

All remains quite quiet at the owl box – surely the bird is still on eggs? Arrangements are now all in place for the bird ringers to look in the box on Friday.

The bullfinch are back in the wood for their summer breeding and it’s lovely to see them again. When they are here they are frequently on the cameras because they love to bathe:

I have not seen any badger cubs this year yet, either in the meadows or the wood. It is always a surprise to see a badger out by day and so far from a sett:

I finish today with plant that grows near my brother’s house in North Somerset. It’s the purple gromwell – a native plant that is now very rare, occurring in a few places in the South-West and Wales. He stumbled upon it by accident a couple of years ago but now visits every year.

I had hoped to accompany him this year but it is looking like it is going to have to be next year now.

Springtime Woodland Wonders

It is a beautiful time of year and in the wood the primroses have now been joined by bluebells, just as the trees are beginning to unfurl their fresh green leaves. One evening I was walking around the wood collecting cameras, with half an ear listening out for nightingales which had been heard in the larger wood last year. I didn’t hear a nightingale, but something else rather wonderful happened. Standing close by the old cherry tree where woodpeckers have traditionally nested, a green woodpecker reversed out of a chest-high hole just a couple of feet away from me. It emerged looking dishevelled as though it had just come through a hedge backwards and I am not sure which of us was more surprised. Before I left the wood that evening I had moved a trail camera across to look at the hole:

We think that this hole is new and so presume that the green woodpeckers have drilled it themselves. In previous years they have reused an old great-spotted woodpecker hole – green woodpeckers have softer beaks than other woodpeckers and will choose to adopt an existing hole if they can
A confrontation with a squirrel

I might not have heard a nightingale in our wood yet but John, the bird ringer, photographed one this week at Stodmarsh, a nature reserve near Canterbury:

Every year the number of bluebells in our part of the wood is increasing. The British native bluebell, Hyacinthoides non-scripta, has lovely arching stems from which the flowers dangle:

Hyacinthoides non-scripta, our native bluebell

Looking up into the bell of the flowers, the pollen is white:

Hyacinthoides non-scripta

The bell shape of the flowers suggests that it is a long tongued insect that pollinates them and, indeed, from my reading I learn that it is mainly bumblebees that perform this job. But standing surrounded by a sea of countless thousands of bluebells this week, there is only a drone of a single bee that I can hear – there cannot be much pollination going on. The plants do also produce bulbs asexually and my guess is that this is how they mainly reproduce, rather than by producing seed.

There are no native bluebells in our garden but a previous owner had planted Spanish bluebells, Hyacinthoides hispanica. A native of the Iberian Penninsula, these bluebells are more vigorous plants and have thicker, straight stems, broader leaves and paler flowers, which are attached all around the stem rather than dangling down on just one side:

Hyacinthoides hispanica in the garden

These Spanish bluebells have blue pollen:

Admittedly these are still beautiful plants, but not a patch on the delicate elegance of our native bluebells to my mind. There is also a problem – the Spanish bluebell has escaped from our gardens and hybridised with our native plants, producing a fertile hybrid. A survey by the charity Plantlife showed that one in six British broad-leafed woodlands had either the Spanish bluebell or the fertile hybrid growing within it which poses a real threat to the genetic make up of our precious native bluebell population. Since the UK’s woodlands are home to more than 50% of the global population of Hyacinthoides non-scripta, this is a big concern and we are advised not to grow Spanish bluebells in rural gardens and to dispose of Spanish bluebell bulbs and cuttings very carefully.

There is a clearing in the wood where marjoram grows strongly and, when this comes into flower later in the summer, the place becomes a butterfly wonderland. But, at this time of year, it is the blue spires of bugle that are pulling in the pollinating punters and the whole space is alive with insects when the sun shines:

I feel that bugle is very underrated plant
Dark-edged bee-fly drinking from the bugle flowers
Bee-flies have now gone for this year from the meadows but they are still holding on in the wood. This is a dotted bee-fly with spotted wings and the white dots down the abdomen that tell us that this is a female
Here she is again, not quite in focus as usual, but showing her white spots well as she visits a speedwell flower

As I was standing in the patch of bugle, I saw a bee that I didn’t recognise:

Yet again, not in focus but she just wouldn’t stop moving

She is a hairy-footed flower bee.These are solitary bees with no social structure but they often nest together in groups in the soft mortar of walls or in exposed soil on banks. This female is mostly black other than orange hairs on her hind legs and she is busy gathering pollen from the bugle to take back to her nest.

I wanted to get a better photo of a hairy-footed flower bee – one that was in focus at least – and sat on a tree trunk surrounded by the bugle and waited. This time I didn’t see a flower bee but I found something even more amazing. All around me there were red-bottomed bees that flew low, landed on the short-cropped vegetation and immediately disappeared as they moved down beneath the leaves – they were very difficult to photograph but eventually one landed in the open and paused long enough to give me a chance:

Very bright orange abdomen and legs
Really a very bright orange

I then realised that these bees were picking up sticks and flying around with them and often these pieces of stick were several times longer than the bee herself. It was an entrancing spectacle but one that I was far too slow to capture photographically. This was the best that I achieved:

This bee had just landed having been flying around with the stick that is under her

I didn’t know what bee made a nest out of this sort of material but, once I got home, I quickly identified her as a two-coloured mason bee (Osmium bicolor). Interestingly, these bees make their nests in empty snail shells. Depending on the size of the shell, she makes up to five nest cells within it, divided from each other by walls of chewed-up leaf. The shell is then camouflaged under grass, leaves and sticks.

I never did get a clearer photo of the hairy-footed flower bee, but I had discovered something very special instead.

A comma sunbathing on the woodland floor
One of the thirty species of nomad bees in the UK that are often tricky to identify. Nomad bees are cleptoparasites on Andrena mining bees – they are looking to lay their eggs on the stocks of pollen that their mining bee hosts have collected for their own young
Sweet little fox cubs are now turning up on trail cameras throughout the wood

I have had a camera on a hole in the ground for a couple of weeks and have seen foxes, badgers, squirrels, jays and rabbits looking in it:

There are plenty of small rodents in and around the hole as well:

And this was probably what interested this tawny owl to also peer down the hole one night this week:

There is very little activity at the tawny owl nest box and I believe that the owls are quietly sitting on eggs in there still:

An adult owl going into the box

Two large owlets were ringed in this box on 2nd May last year. Tawny owls usually lay two eggs and can it be that neither of these eggs has even hatched by the same time this year? The bird ringers, John and John, have been discussing strategy and I think that they have decided to look in the box towards the end of next week and see what is inside. Will there still be eggs and an adult inside, or will there be chicks? Or have I got it completely wrong and will there be squirrels? There is not long to wait now until we find out.