View of harbour mouth
The first stop of this tour looks from the end of West Wittering beach across the mouth of Chichester Harbour towards Hayling Island.
On a clear day it is possible to see the Isle of Wight in the distance.
Click to view panorama of East Head
The mouth of Chichester Harbour has changed dramatically in size and shape over time. For example, between 1840 and 2000 the cross sectional area has doubled from 25,000m2 to 50,000m2. Boats coming in and out of the harbour need to keep to the deepwater channel, which is on the Hayling Island side of the harbour mouth. Those that don’t do this are in danger of ‘going aground’ on the Winner Bank.
From this position we can see several features that have affected the changing shape of East Head: the Winner Bank, the end of the groyne field and the rock groynes on Sandy Point beach, Hayling Island.
Notice the tamarisks growing in this area. These shrubs are found frequently around the harbour because they can tolerate dry and salty conditions. The tamarisk is not an indigenous plant but has been introduced from warmer parts of the globe.
West Wittering beach with it’s endless stretch of sand is probably the most popular beach in the area. It is estimated that over a million visitors visit West Wittering beach and/or East Head spit each year by road.
East Head itself receives many visitors by boat, who anchor at the north end of the spit.
www.westwitteringbeach.co.uk
This is an important stopping place for visitors and is therefore dotted with signs to inform and educate people who have come to the beach or walk on East Head.
Gabions have been very effective in protecting this section of the Hinge. It is possible to see where previous gabions were constructed.
Click here to find out more about gabions.
The groyne field consisted of only 23 groynes until the early 1980’s when Groyne 24 was built.
There is wide overlapping of habitats on this part of the Hinge, and the plants found represent this and are quite diverse. Look out for plants from vegetated shingle, dune, saltmarsh and shoreline habitats.
Click here to find out more about these habitats.
Groynes are structures that extend perpendicularly from the shore. They are normally constructed in groups called groyne fields.
The function of a groyne field is to trap and retain sand and shingle that is transported via longshore drift
Click Here to see Longshore Drift in Action
This material then nourishes the area of beach between the individual groynes. When a well-designed groyne field fills to capacity with sediment, longshore transport continues at about the same rate as before the groynes were built and a stable beach is maintained.
The groyne field consisted of only 23 groynes until the early 1980’s when Groyne 24 was built.
The usual direction of longshore drift around the coast of Britain is from west to east. The longshore drift that approaches East Head comes from east to west.
Click here to see a diagram of the sediment
transport around East Head.
This is currently the weakest spot of East Head and has been the focus of much attention over the last few years.
Management practices in neighbouring sections of the coast have caused less material to be available to be transported by wind and waves to this part of East Head and so the dunes have not been replenished.
In 2000 a rock berm was constructed along the eastern side of the Hinge to prevent the sea breaching this area and causing a new tidal channel to form. This would have resulted in East Head becoming an island and large quantities of sediment being redistributed and possibly affecting the deepwater channels. Planning permission was given for the berm to remain for 5 years.
This posts show where the dunes extended to approximately
20 to 30 years’ ago.
The sandbank that you see at this location is quite a new structure. It was created in June 2005 after a stormy high tide in October 2004 had washed away the final narrow bank of dunes.
This section of dune cliff is presently one of the most vulnerable sections of the dunes. It is exposed to the southwesterly wind; the existing dunes are being eroded and no new dunes are forming. Sometimes there are small landslides when whole chunks of sand dune break off.
Please do not climb up or on this part of the dunes. It can be very dangerous and you will also cause the dunes to erode more quickly!
The roots of the Marram Grass that still binds these dunes together are very clearly exposed. Salt water spray from waves hits the roots and causes the plant to die off more quickly.
Sometimes rope fencing has been placed across the dune cliff to discourage people from adding to the erosion and to protect them should there be a sudden collapse of sand.
Unfortunately not everyone respects the boundary of the fence line and as a result this vulnerable section of the dunes is weakened even further.
For the past few years two pairs of ringed plover have nested in this area. They lay their eggs on the ground and these are camouflaged to look like large pebbles. The nesting area has been fenced off to prevent the birds being disturbed and their eggs trodden on.
Find out more about ringed plovers here:
RSPB Website
birdguides.com
Another advantage of this fencing has been to prevent trampling of plants and embryo dunes. In this picture you can see how the section of embryo dune to the right is thriving because it is fenced off, while on the left it has almost disappeared.
The plants growing in the shingle make what is known as a vegetated shingle beach. Vegetated shingle is a nationally scarce habitat that sometimes suffers great disturbance when stones and shingle are constantly moved around by incoming waves from the sea. The rare Sea Knot Grass that grows close to the surface of the shingle varies in the size of its population from year to year because of this disturbance.
There are good examples of embryo dunes forming at this end of the spit. The sand from the southern end of the spit has gradually migrated to the northern tip. When the wind blows in a northeasterly direction, sand can be seen blowing across the surface of the ground and is easily trapped by any obstruction. If the obstruction is Marram Grass then there is every likelihood that the embryo dune will gradually increase in size.
The northern tip of East Head can look very dramatic at low tide. The sand and shingle form a very steeply cut bank. When the wind is strong the sand blows across the surface of the beach rather like a storm in the desert. It is possible to see the line of fast growing sand dunes on Pilsey Island from this position, when you stand looking northwards into the harbour.
The deposition of sand and shingle in this area is causing this part of East Head to bulge in shape. Compare the shape of the spit now to how it was during the 1970’s.
Click here to discover more about the Changing Shape and Direction of East Head
The green East Head channel marker is only a short distance away. This marks the edge of the deep water channel which could be threatened if East Head continues to accrete sand and shingle in this area.
Click to view panorama of this stop
When the bank near the Hinge was constructed in June 2005, the material was excavated from this area and transported to the breached area.
Click here to discover more about this
This is another busy part of East Head. During the summer many people travel to East Head by boat and moor off the northern tip of the spit where there is sheltered anchorage from the prevailing wind.
They come ashore to enjoy the sandy beach and as a result the edge of the dunes gets very trampled and eroded.
This could be a problem if there was not heavy deposition to compensate for it.
The dunes at this end of the spit are healthy and the Marram Grass flourishing.
Click here to find out more about Marram Grass.
It is a good place to find sand lizard footprints trailing through the sand. You may even be lucky enough to spot a lizard, but they tend to be rather shy!
Because this is a heavily visited part of East Head there are several notices to caution or inform.
The small area of the dunes that has been fenced off is home to the Silver Spiny Digger Wasp. The wasp burrows into the dunes to breed. It catches other invertebrates and injects them with a poison that paralyses but doesn’t kill.
The prey is then carried into the burrow and becomes a ‘living larder’ for the wasp grubs.
The very distinct hook is a natural feature
of sand and shingle spits.
Click to discover how a spit is
formed
A hook is formed when storm waves deposit material on the sheltered side of the end of a spit, causing it to migrate landwards. This is process is enhanced when the oblique waves that cause longshore drift swing round the end as they meet open water.
This could be a problem if there was not heavy deposition to compensate for it.
Snow Creek saltmarsh fills most of the sheltered area behind the spit.
Parts of the saltmarsh have also been destroyed by trampling and so it is constantly monitored.
There are some interesting patterns of sediment deposition in this area. The north-easterly wind causes sand to be deposited at the back of East Head and a process of ‘infilling’ is taking place. Some sand is even beginning to cover parts of the saltmarsh.
There appears to be a slipper limpet ‘graveyard’ quite close to the hook. These light shells are moved around by currents and deposited in one place with the ebb and flow of the tide.
Slipper Limpets were accidently introduced to this country from North America at the end of the 19th century. They are a very dominant species on the south coast and have caused a decline in oysters because both are filter feeders and share the same food source.
This creature has very strange breeding habits that you can read about if here
From this position you can look across the extent of the dunes and see the succession from embryo stable and mature dunes, where scrub is beginning to establish itself.
Read about the Ecology of East Head
The low-lying dark patches are called ‘dune slack’ or ‘grey slack’. These slightly sunken areas collect pools of fresh water because of the high water table, and so a more varied type of vegetation begins to establish itself.
The vegetation mostly consists of sedges and rushes but even the Common Reed (Phragmites australis) grows here.
Click here to find out more about plants that
thrive in very damp environments
There is a thriving population of rabbits in the dunes. Their grazing habits keep the vegetation very short. A kestrel hovers frequently the dunes and smaller birds such as Meadow Pipits and Skylarks are also abundant. However, these may be threatened by disturbance as they build their nests on the ground.
These have been laid across the dunes to encourage visitors
not to trample the vegetation.
As a result plants and ground-nesting birds are less disturbed. Boardwalks are constructed of wood and are suitable for a natural landscape.
They are flexible in that they can traverse uneven ground and can be removed or replaced easily.
Unfortunately sections of boardwalk have disappeared on occasions when thoughtless visitors have decided to use the wood for their barbecues!
Click here to find out more about the flora and
fauna of the dunes.
