Monday, 18 June 2018

Walking the Humber. Stage 17. The Warren to Spurn Head

I got up at 6 am to make it across the breach to Spurn in good time ahead of the high tide at 9:30. An Oystercatcher is feeding on the car park and flies to the top of the Discovery Centre. A Fox scuttles ahead on the path. There are lots of rabbits about.
I press on across the breach. Swifts fly overhead in twos and threes all day: the non-breeders departing early to their winter quarters in Africa. Spurn Head is a 5.5 km long spit that has been a YWT reserve since 1959. The spit curves inwards in a SE direction towards the Humber forming the Spurn Bight.
 Once I cross the breach, I walk on the estuary side on the beach, which shows a succession of saltmarsh plants.
Migrants
Spurn is very well known for bird migration, but is also a hotspot of insect migration with an impressive list of dragonflies and butterflies, including rare migrants. Since 2013 there has been a very successful Migration Festival organised in early September by Spurn Bird Observatory Trust, the British Trust for Ornithology (BTO) and Westmere Farm at Kilnsea.

Ecology
Dunes are a large part of the peninsula. Marram Grass Ammophila arenaria and Sea Buckthorn Hippophae rhamnoides are abundant. In the dunes there are plenty of specialist dune invertebrates. George de Boer quotes this 1567 description of the ecology of Spurn:
 'Ravensey Spurn is a sandy hill environed and compassed about upon the sea side with the sea and on the other side with the Humber containing six acres whereupon is neither arable land, meadow, nor pasture, wood, underwood nor trees neither anything else but only a few small bents and short scrubby thorns of a foot high not worth felling, which Ravensey Spurn is at ordinary spring tides almost overflown and of no value. Also there is another hill nigh adjoining the Ravensey Spurn called Conny Hill environed with the sea containing four acres whereon is neither arable land nor trees also of no value'.

Dynamic spit system
Spurn is in a balance of erosion of the low glacial till cliffs and sand and shingle deposition. Historical accounts and maps give us a glimpse of how much change there has been, with the narrow neck at times breached by storms or broken into a series of shallow banks, with an the island at the point slowly shifting position westwards. In the Middle Ages, a precursor of the island had a busy port and town, Ravenser Odd -with over 100 houses and fields. The town entirely succumbed to the sea in the few decades up to 1360. The spit topology and movement is also influenced by the erosion of the soft till cliffs of the Holderness coast to which it is anchored. Erosion is highest between Easington and Kilnsea (estimated at more than 2 m per year). Coastal erosion provides the sediment that, transported southwards by longshore drift, is deposited along and beyond the spit, increasing its length. As the coast erodes the neck becomes more exposed and can be breached by winter storms. Since Victorian times, sea defences with groynes and sea walls, which now are not maintained, have also affected the development of the spit.
Looking towards the breach

Future: Spurn island?
Spurn has existed as a spit before, but several breaches in historical times resulted in Spurn island being formed. On 5th December 2013 a tidal storm surge breached the neck of the spit, destroying the road and services linking the mainland to the coastguard station in the head itself. Since then, the YWT regularly runs trips in a Unimog vehicle to link the mainland to the point and the lighthouse, whose refurbishment finished after the storm breach. The 'breach' can be flooded at high tides so it is advisable to check tide times as crossing when there is water on the breach is extremely dangerous.
A lone Dark-bellied Brent Geese by the breach.

Dune invertebrates
It was great weather for invertebrates today, with long sunny spells. Many butterflies and other insects were about.
A Silphidae beetle for ID. 
There were many Dune Chafers, Anomala dubia, on the dunes at the very tip of Spurn.
Early in the morning the sandhoppers, Talitrus saltator, were very active on the beach.
Dune robber fly, Philonicus albiceps.     
Cinnabar moth.
A brown-tailed moth caterpillar climbing the lighthouse. These caterpillars form silk tents in bushes, which they defoliate. When large, they abandon their tents in search of food and pupation sites. They are very common at Spurn hairs are irritant. Today there were not many about.
Dune plants
There are many plants flowering. I took a selection of photos.
Sea Bindweed, Calystegia soldanella.
Restharrow, Ononis repens.
Sea Holly.
Pyramidal orchid, Anacamptis pyramidalis, flowering at Chalk Bank.
Breeding birds
Whitethroats provided the soundtrack today. Singing scolding short chattering phrases from atop bushes or posts. They were joined by other resident birds: Reed Buntings, Linnet, Wren, Carrion Crows, Magpies and Meadow Pipits are also breeding around Chalk Bank and Potato Fields. In the scrub at the point there was even a Blackcap singing. 
Whitethroat singing.

The hide at Chalk Bank, overlooking a bank and pools where waders and gulls roost at high tide.
I counted about 200 Oystercatchers at Chalk Bank...

...a Cormorant...
...and two Curlew.
An assortment of gulls, including Herring, Lesser Black-back and Great Black-backed gulls loaf on the sand bank. Common Gulls, Black-headed gulls and Sandwich terns were also about.
A pair of Shelduck matching their surroundings beautifully. 
Linnet with young (on the left).
Young Pied Wagtail near the tip.
  The walk on the path on Chalk Bank and Potato Fields was lovely, Small Heath, Red Admiral and Common Blues were about. On the background on the right the Heligoland trap, a funnel that allows to trap migrant birds, which are then ringed and released to understand migration.

The high and the low lighthouse at high tide.
The lighthouses
A request for a lighthouse in Spurn is the second recorded in the British Isles, possibly as early as 1427 in what was known then as Raverser Spurn. The history of the various Spurn lighthouses, as there has been several, has been choppy to say the least, stirred by obstinate landowners and the unpredictable forces of nature changing the length and location of the spit, and emerging sand banks. A detailed account of their history has been written by de Boer. The current high lighthouse, a Grade II listed building, was erected in 1893 and restored in 2015. Today it was closed but it is regularly open to the public and you can climb to the top and enjoy great views over the peninsula and the estuary.
Spurn Point
The tip of the peninsula widens into a spoon shape. It is surprisingly wide, over 200 m, and sticking out into the Humber is the jetty of the Humber Lifeboat Station (above). The centre of the tip is scrub of sea buckthorn, and other bushes and small trees. There are several mowed paths leading to the edge, where there are dunes covered on marram grass. I watch as large ships move onto the Mouth of the Humber and look across the estuary: this is the end of the walk proper, the end of the north shore of the Humber. 

Path to the tip. A Speckled Wood flew away, not a butterfly I expected here.
Small Tortoiseshell Caterpillars.
I walk around the eastern side of the peninsula. Two Ringed Plovers fly off from the beach, joining a dozen Sanderlings. A lone Knot feeds on a shingle bank, the Stony Binks.
Sanderlings.
Knot.
The high dunes just before the lighthouse. There has been a lot of erosion near the lighthouse and I had to scramble up the dune to rejoin the path.
Back at the Warren
I walk on the road from the lighthouse and through the path at Potato Fields and Chalk Bank, back through the breach and to the Warren. I hang around Clubley's scrape to look at Dragonflies and then to the Discovery centre for lunch. After lunch I watch dragonflies from Canal Scrape hide. For the first time I see Emperor dragonflies mating and ovipositing.
A young rabbit relaxes on the Warren.
Black-tailed skimmer.
Teneral female Common Blue Damselfly.
A teneral Ruddy darter (I think!) near Clubley's scrape.
Linnet bathing on the new pond.
An Emperor dragonfly settles on the grass to eat its prey.
Black-tailed skimmer female, resting on the board walk to the Canal Scrape hide.
This Swallow, breeding inside the Canal Scrape hide was bringing some damselflies for its young.
Ovipositing Emperor dragonfly at Canal Scrape.
Today's stage: 13 km round trip. The end of Walking the Humber.

More information
de Boer, G. 1964. Spurn Head: Its History and Evolution. Transactions and Papers (Institute of British Geographers) 71–89 .
Roadhouse, A. 2016. The Birds of Spurn.

Monday, 11 June 2018

Walking the Humber. Stage 15. Kilnsea Wetlands and the Spurn Triangle

A sunny, warm day I headed to Kilnsea for the penultimate stage of Walking the Humber, featuring the area south of long bank: Kilnsea Wetlands, Beacon ponds and the 'Spurn Triangle' up to the Warren, including the new YWT Spurn Discovery Centre.
 I park at Kilnsea Wetlands and walk to the hide. A Four-Spotted Chaser is hunting and resting on the drain by the path to the hide.
Kilnsea Wetlands
This is a very new nature reserve managed by the Yorkshire Wildlife Trust, only a few years old, but that has developed and matured quickly. It consists on several scrapes and is grazed by sheep, including a Hebridean flock. It was created to compensate for the loss of wetlands in the area due to coastal erosion. Many birds use it, including waders at high tide. Today it was busy, with families of starlings feeding on the edge of the main pond. A pied and a yellow wagtail hovered just over the water surface capturing insects. The Yellow Wagtail was carrying food for young. There were at least two pairs of Avocets, and two chicks. Mute Swans, Teal, Gadwall, Wigeon, Greylag and Mallard, the last two with young, were about. Skylarks sung over the reserve.
As I left the hide, a Painted Lady was sitting on the path, and a Large Skipper and a Wall Brown butterfly were also about.
The only Black-bellied Brent Geese I saw today was grazing at Kilnsea Wetlands.
This Little Egret was very successful fishing Sticklebacks.
Painted Lady, this individual with tattered wings is likely to have travelled from the Mediterranean. My first one of the year.
 
Hovering Yellow Wagtail.
Now with a bunch of insects for its brood.
Yellow Wagtail and Avocet chick.
Wall Brown.
Beacon Ponds
This set of lagoons and sand dunes, now being eroded by the sea has held a Little Tern colony for over a century. The colony of about 25-30 pairs is wardened and surrounded by an electric fence to protect the nests on the ground. Beacon ponds often has  and many other birds. Today there were some Sandwich Terns, several Avocets, a Cormorant, a Dunlin and two Oystercatchers, in addition to the Little Terns of course!
Blue-tailed Damselfly.
Two Little Terns by their sand and shingle colony.
Sheep grazing by a scrape covered on flowering crowfoot. The sound mirror in the background.

Beacon Lane
I move onto Beacon Lane, usually really good for invertebrates. There were several patches of Bird foot trefoil in bloom, with several Common Blue butterflies on them.
Male Common Blue
Reed Bunting singing.
Female Common Blue.
Spider for ID.

The Triangle
I walk east by Easington Road towards the Crown and Anchor to walk by the Humber towards Canal Scrape. Families of starlings feed by the sea wrack. The tide is quite low and it is starting to get warm.
A Small Heath on the Blue Bell car park.
A family of Starlings feeding on flies on the sea wrack.
Emperor dragonfly on Canal Scrape.
A large and stunning soldierfly, a female Flecked General Stratiomys singularior (I think, awaiting confirmation). It is a species of grazing saltmarshes.
Four spotted chaser on Canal Scrape.
The Mute Swan pair of Canal Scrape had 8 young.
A rabbit in the Warren.
Canal Scrape and Clubley's Scrape
After lunch in the cafe of the Discovery Centre, I spend some time watching dragonflies around Canal Scrape Clubley Scrape (above) and the newly dug ponds near the Discovery Centre. Black-tailed Skimmer were very obvious, I only saw males, some immature. The Four spotted Chasers fought them off repeatedly. There was a resident male Emperor in at least 3 of the ponds. I found a darter but I couldn't get a good view or a photo. 
Black-tailed Skimmer.
Male Emperor taking a break on the edge of the pond.
An ovipositing Four spotted Chaser female. She dips her abdomen in the water repeatedly and you can see the ripples on the water where she just did.
A view of the Discovery Centre from the sea bank.
As I returned to the car, pairs or trios of Swifts, probably non-breeding individuals, were already migrating south.
Next and final stage will feature the lighthouse and Spurn Head peninsula.
Today's walk, about 9.6 km.