Recent Sightings - August

August seems to have been the month of change, and I don’t just mean the weather. Change is definitely in the air as small flocks of birds begin to migrate.

Autumn’s passage waders are a little stop start at the moment with 100+ Curlew, 5 Greenshank, 6 Green Sandpipers, 1 Common Sandpiper, and 7 Wood Sandpipers gathering on the pools at Holkham. Yesterday there were signs of Spotted Redshank with their silvery grey and white winter plumage, Ruff and a Jack Snipe near Washington Hide.

Can you spot these camouflaged 

Snipe at Washington Hide? 

 It’s also been a good time for passage migrants. These birds pass through the British Isles in autumn on their way south to Africa having spent the summer in northern Europe. There have been several sightings of warblers including a good showing of an Icterine Warbler. Many people had excellent views of this traditionally shy bird however, that cannot be said of a young Barred Warbler, which stayed well hidden in the dunes. The numbers of other warblers arriving are also slowly increasing such as Blackcap, and Whitethroats. Common migrants have also been arriving in good number. Wheatears and Redstarts have joined the growing number of Whinchats. Even a Red-backed Shrike was seen dropping into the sloe bushes on the Holkham-to-Wells Backtrack.

Look out for migratory tit folks as they may

 shelter rare birds including Yellow Browed Warbler.

A Great White Egret is well into its 2nd week on the reserve and has settled on the scrape nearest Decoy Wood. Although it is only appearing now and then, with a lot of patience and a bit of luck you can get a good view as it stalks the shallow waters of the dykes along the grazing marsh.

A rather raggedy Great White Egret.

Despite the recent rain, birds of prey have been showing regularly including Marsh Harriers, Kestrels, Sparrow Hawks and Common Buzzards (2 in stunning pale plumage) and an often-seen Peregrine Falcon (outside Jordan Hide). In the last few days a Short Eared Owl has also been sighted dropping into the dunes at Burnham Overy.

In contrast, sea-bird sightings on the reserve have been very poor with only a small group of Gannets seen passing far out to sea. However, the bad weather did sweep in an unlikely Little Gull into the Overy dunes/Gun Hill area of the reserve.

Keep an eye out for late butterfly's and their chrysalis 

like this beautiful gold Small Tortoiseshell chrysalis.

The rain flatted much of the tall grass, and as a result conditions were great for mammal watching. Common and Short-tailed Shrews could be seen moving thorough the grassy verges  (and often being eaten by Herons!)

With the start of September we can look forward to many more migrants arriving and passing through Holkham NNR. With north winds we should see the arrival of the first flocks of Fieldfares and Pink-footed Geese!

The Dunes of Holkham

 When most visitors think of Holkham they think of its unspoilt beach and stunning sand dunes. The sand dunes are a key feature of the area and this has led to many people asking me, how they were formed.

There are approximately 11,897 ha of sand dunes in England with 1,200 ha here in Norfolk.

Dune grassland and dune slacks support a wide variety of plants and are rich in invertebrates. The dune system at Holkham is protected by a number of conservation designations, such as SSSI and SAC. This is the reason why horses and bikes are not allowed access through the dunes.

Along with the beach, the dunes are one of Holkham's 

most famous features.

The sand dunes at Holkham were formed because there is a large beach plain, so plenty of sand. The surface dries out between high tides, and then dry sand is blown landwards by strong onshore winds and deposited along a shingle ridge above the high water mark. At Holkham the dunes are unusual as they are rather alkaline due to the amount of shells in the area.

Embryo Dunes are the first stage. There is very little vegetation and sand is only just starting to accumulate.

Lots of bare sand and

 little vegetation.

Foredunes are part of the sand dune system on the side nearest to the sea. They are comprised of wind blown sand and scattered plants, such as sand couch-grass and sea rocket. As embryo dunes build up, the surface is raised so as to be out of reach of all but the highest tides.

Large hillocks of Marram grass.

Yellow dunes are yellow in colour because of a lack of soil. They are dominated by marram grass. Marram grass is tall, robust, flexible in the wind and very effective at trapping sand. Their binding rhizomes help stabilise the sand dunes and enable other species to grow, such as sea sandwort. The dunes grow to around 5m.

Vegetation has become varied and dense.

Grey dunes are grey in colour because of the presence of soil. As dead leaves from the marram grass breaks down so plant nutrients are released into the soil improving the conditions for plant growth. Due to an increasing distance from the sea vegetation diversity increases, though the plants are still highly specialised. Marram grass is still abundant but other species are able to colonise the area, such as red fescue and bird’s foot trefoil. Grey dunes grow to between 8 – 10 m high.

Core samples have shown that the Holkham dunes are 

200 years old!

Dune Slacks occur when the surface of the sand dune is eroded down to the water table and wet sand is exposed. A secondary dune slack can have the appearance of a bomb crater! Dune slacks can be extremely species rich. As well as rare orchid species there are a number of uncommon species of butterfly, dragonfly and the very rare vulnerable natterjack toad.

Dunes slacks are rare and unique habitats.

Through careful sympathetic management the warden team aim to ensure that there is a succession of dune slacks at different stages of re-colonisation, thereby providing a habitat for rare flora and fauna, to control the invasion of non-native species and to protect the sand dunes from erosion by recreational use.

When you next walk along the dunes at Holkham National Nature Reserve why not try and identify these stages. The coast is always changing so there is always something to see!

Happy Hunting

Jonathan Holt
Warden

A Life on Ragwort

Common Ragwort (also known as Stinking Willie) is a native biennial plant which often grows naturally on uncultivated land. The problem with Common Ragwort is, it is toxic  and if left unchecked can seed through large areas. Ragwort is poisonous to livestock especially horses but fortunately most mammals are aware of its toxicity and avoid eating the plant. Ragwort is very distinctive with finely divided deep cut toothed leaves and large flat-topped clusters of yellow daisy-like flowers. It flowers from July to October and is a good late nectar source for hungry insects.

Despite its hazards many species depend on Ragwort and live their entire life cycle on the plant. Therefore, Holkham National Nature Reserve takes a balanced approach. Ragwort does need controlling but not eradicating and we take all reasonable action to do this on the nature reserve. We manage the spread of Ragwort on the grazing marsh by grazing cattle but as a natural dune flora Ragwort is left unmanaged on the dune system.

Ragwort will quickly take over a field if it isn't controlled.

Wildlife

Cinnabar Moth Caterpillar

Ragwort (mainly common ragwort) is the sole food plant for the golden and black banded caterpillar of the Cinnabar moth. The caterpillars feed from July to September and act as a biological control by eating the whole plant. The poison from the ragwort leaves is stored in the caterpillar's body. The bold colours and patterns are a warning to birds and other predators that they are extremely unpleasant to eat.   

These caterpillars are both eye 

catching and alarming at the 

same time!

Bumblebees

Bumblebees are a familiar sight during hot summer days with their characteristic behaviour and distinctive buzzing sound. Sadly, bumblebees are in massive decline due to the reduction and removal of hay meadows and hedgerows from the British landscape. Ragwort flowers are an important source of food for many bees. These include the obvious Red-tail Bumblebee, the bird box dwelling Tree Bumblebees and the distinctively ginger Common Carder Bee.

A Common Carder Bumblebee 

(unfortunately not on a Ragwort flower!).

Forester Moth

This exquisitely coloured metallic-green and remarkably well camouflaged moth is a UKBAP species. It is thought to of been named after the "Lincoln Green" worn by the foresters in Sherwood Forest. The species is in decline but can be found locally in the coastal marshes and around damp meadows. We found this fellow while ragwort pulling on the Fort. It just goes to show the diversity of species that can be found on ragwort.

A lucky find!

Cockchafer Grub

Possibly the most unluckily named insect out there, it is also known as the Maybug though it's not a bug, these large beetles actually belong to the scarab family. The harmless beetle is a distinctive brown colour with characteristic fan like antennae. Cockchafers spend most of their lives (three to four years) underground as larvae. The larvae (which are called Rook Worms) are fat, creamy-white grubs with brown heads that feed on the root systems of ragwort. In turn these grubs are fed upon by badgers, owls and bats!

Both adults and grubs are considered 

a delicacy and are still eaten in some 

countries.

Jonathan Holt

Warden

Recent Sightings - July

Firstly, I must apologise for no updates recently. We have been unbelievably busy on the reserve and I must admit to a few days holiday.

The month started warm and sunny with lots of bird and invertebrate activity but it's ended cool, wet and very windy, causing bird and invertebrate activity to become subdued.

On site there has been a good selection of waders spread right across the marshes with up to 100 Black Tailed Godwit, 24 Avocet, 4 Spotted Redshank, 5 Greenshank, 17 Redshank as well as Curlew, Oystercatchers and a good number of Ruff. The males are looking rather attractive with their wide variety of different plumage due to their various stages of moult. In the evenings it is always worth looking upwards particularly at high tide as we have had almost 100 Common Scoters fly past!  And, the odd Whimbrel has been seen passing over the reserve flying west.

A lonely Curlew surveys its watery

 territory during high tide at Norton.

Other notable birds include plenty of Little Egrets that can still be seen hunting in the shallow dykes. A Green Woodpecker family has been very noisy in the pine woods at Holkham NNR and a lucky Quail that survived the guns of Malta was heard (but not seen) by myself and others at Whincover.

There have been excellent sightings of Marsh Harriers from both hides. As you approach the reserve you can get some stunning views of the harriers with newly independent youngsters hunting in the fields near the coast road giving some good photo opportunities. There has been plenty of Red Kite activity and the odd Buzzard too but no more sightings of the Short eared or Little owl. Barn Owls have been showing very well especially near Washington Hide. Early evening is the best time to see them but remember the reserve gates are being locked at 9:00pm very evening until October.

Unlike their Hen Harrier cousins the Marsh

Harrier is slowly recovering from near 

extinction in Britain but they remain rarer 

than Golden Eagle.

I enjoyed a very interesting evening while walking through the reserve last week. I saw 16 Brown Hares grazing and chasing each other in the fields (they have a long extended breeding season, so are still quite frisky) then, some lovely Roe Deer on the old railway line but the evening was to get even better when, walking through the Natterjack ponds I noticed a young Hedgehog sat right in front of me. It decided it was quite comfy where it was and sat there until I had to go home.

Due to the mostly nocturnal nature of Hedgehogs it is 

difficult to assess their numbers on the reserve.

There were a lot more butterflies at the start of the month when the weather was warm and sunny such as Grayling, Essex Skipper and  White Admiral, dragonflies included Emperor and Southern Hawker as well one of my personal favourites, the Hummingbird Hawk Moth. However, despite the recent cool wet weather there are still several species still active, such as Forester Moth, Gate Keepers Butterfly and Ruddy Darters.

The Emperor is one of the UKs largest 

Dragonfly's it is brightly coloured and 

rarely lands even eating its prey on the wing.

I’m still pretty disappointed that the Minsmere Albatross didn’t pay Holkham a visit but maybe next time.

Jonathan Holt

Warden

The Hunt for Yellow Bird's Nest

For the past three weeks Thomas has been working alongside the Holkham National Nature Reserve wardens on work experience. We very much appreciate Tom's hard work and enthusiasm and he has written an entry into our online diary about his experiences of working on the reserve. Over to you Tom!

One of my biggest challenges during my volunteering at Holkham was the hunt for the Yellow Bird’s Nest. Funnily enough I don’t mean the nest of a yellow bird, or a bird’s nest that is yellow. Yellow Bird’s Nest is a plant. For some reason. The Bird’s nest is an odd looking, fleshy plant not unlike a yellow asparagus. It’s very rare and (rather than photosynthesis) feeds parasitically on the fungus which lives in the moss upon which the Bird’s Nest grows.

As one of the rarer plants on the estate it was mine and the warden’s job to find and record the Bird’s Nest. This...proved more difficult than expected. The first clump of bird’s nest was one that the warden’s had already found a good reference point for me to know what I was looking for. So we started with counting those, and I was pretty proud to have found the most pristine bunch a very photogenic collection of three. 

But after the first group (of 29) we encountered an unfortunate dearth of rare plants. Nothing. For hours. And this isn’t one of those “just after we’d given up we found loads” stories. We didn’t find anything all day. That’s nature for you really. You don’t always find what you want and in a way that’s part of its beauty. It’s also pretty annoying but silver linings and all. 

Funnily enough it was actually my parents who found more of the Bird’s Nest. They walk the dog at Holkham daily and my mum likes plants so I showed them a picture. And after three days of the wardens and I futilely searching, mum finds three clumps out of the blue. Which we then couldn’t find even despite her directions. 

Finally I managed to see some more of the Bird’s Nest. Not at volunteering, but while walking the dog. My parents showed me the patches that they’d found, which had apparently been conveniently marked with sticks but oh well. I saw them at last even if the wardens didn’t. And learned a valuable lesson about the fickleness of mother nature.

Jonathan Holt

Warden

Fires at Holkham

It’s the time of year when on warm sunny evenings we dust off our old camping gear, check the tent doesn’t have any holes, pack a rucksack full of things we deem essential and set out to find a little corner of the world you can call your own for an evening. However, Holkham NNR, as well as all nature reserves in North Norfolk, has a strict no camping, no bonfire, no gas stove, no barbecue policy. Many people see this as overzealous but these activities pose a very real threat to the nature reserve, wildlife and public, and are sadly a regular problem for the warden team.

Found just in time.

Dunes are a slow functioning ecosystem, they take a along time to recover from damage caused by fire. Whether started accidentally or deliberately fires can quickly become uncontrollable and unpredictable. They can destroy large areas of habitat and kill countless animals. Visitors often think they have put out their bonfire or disposed of their barbecue safely but people don’t realise how hot barbecues get and how the heat from a fire or barbecue can spread by travelling underground and popping up away from the original source, causing a wildfire. This is exactly what happened a week ago. There would have been severe irreversible damage to the pinewoods if a diligent member of the public hadn’t noticed a fire spreading and notified the fire brigade. It took the fire brigade almost 1000 litres of water to put it out.

Yellows Birds Nest is an orchid found only in a few sites in Norfolk.

Fire can have a devastating effect on this fragile and rare plant.

People come to Holkham National Nature Reserve for different reasons. Some people come to see wildlife, some come to enjoy a day on the beach while others walk through the reserve on the Norfolk Coast Path, everyone however wants to be inspired by the beauty of the reserve. Holkham is a source of endless enjoyment for everyone, so let’s work together to preserve this spectacular place.

The pinewood is at risk from wildfires

Please report any fires to the fire brigade immediately and if possible try to give your location and any landmarks. Do not try and put any fires out yourself under any circumstances.

           

Jonathan Holt
Warden

Recent Sightings - June 2015

Blimey! It’s been a sizzling June! With recent temperatures soring over 30^oC it’s been a lovely time to be on the reserve.

The month started with a boom, a Bitten boom that is! Repeated sightings have led to rumours of a breeding pair however our observations thus far have been inconclusive.

It has been a good  year for small birds. The lovely Bearded Tits at Overy have successfully reared at least 13 broods, a great success considering the size of the reedbed! The biggest surprise to me however was finding a Pied Wagtail nest in the woodpile in the work yard. Despite the odds the diligent parents raised 3 out of the 6 chicks (I watched the 2 become Barn Owl food!).

Bearded Tits are funny looking birds! The males

have black 'moustaches' and they are very noisy

and distinctive 'ping' call.

The Kingfisher has been darting up and down in front of Washington Hide from the pool to the dyke. The Crossbills have been very lively in the pine woods and a number of out-of-season Siskins continue to pass through the reserve. Sea birds were making quite a show as well this month with both Max Shearwaters and Gannets passing through.

Kingfishers fly quick and low over slow 

moving water and hunt fish from 

riverside perches such as reeds. 

Occasionally they even hover over 

the water's surface.

Rare sightings this month.

The most exciting rarity this month was a Woodchat Shrike. We found it while conducting a lapwing count at the start of the month. The Shrike was observed making a larder in a nearby blackthorn bush but moved on soon after.

 The prey caught by the Woodchat Shrike 
was taken to a larder where it was impaled 
on a thorn or wedged in a fork and saved 
for later.

A personal highlight for me this month was the Turtle Dove, an increasingly rare sight. This was my first sighting of this very distinctive bird.  Although protected in Britain they are aggressively shot in Malta during migration. Turtle Doves have declined more than 90% between 1997 and 2010 and are now a red listed bird facing the threat of extinction.

The hot sunny weather brought an explosion of invertebrates with large numbers of moths, butterflies and dragonflies. We had one of our most productive trapping days yet. Here are some of the highlights:

Hornet moth

Pine Hawk Moth

Little Elephant Hawk Moth

Butterflies have been adding lots of colour to the day, but they are best seen in the mornings. The highlights are:

White Admiral

Dark Green Fritillary

Large Skipper

Fingers crossed this lovely weather continues and you can come and see the reserve in full bloom!

Happy birding!

Jonathan Holt

Warden