Knitted coral reef

These three old navigational buoys stand about ten feet tall and decorate the dock wall of Sunderland marina. Today when we passed by we found that someone had knitted a gigantic woolly cosy for one of them, decorated with knitted octopus and tropical reef marine life.

This artwork was made by a brilliant group of knitters and stitchers called Materialistics. You find out more their work on their web site 

The artwork was installed for the recent Tall Ships Race and is due to be removed on Wednesday 8th. August.

Feeding frenzy

When we were walking along Whitburn beach in Sunderland this afternoon I noticed a dense flock of about 150 black-headed gulls on the tide line and as we got closer I could see ....

... that they were all picking something off the sand, in a real feeding frenzy.

A closer look revealed many thousands of these tiny white maggots washed in by the incoming tide.

Here they are - the larvae of the seaweed fly Coelopa frigida.

About a week ago we had a spell of warm weather that must have been perfect for these flies to breed in the big piles of kelps and wracks that form natural compost heaps on the beach.

Then two days ago Storm Doris arrived, creating mountainous waves that would have washed the rotting kelps and the fly larvae into the sea.

Today the tide brought them back in again in enormous numbers on this short stretch of beach, providing a fantastic feeding opportunity for the gulls and also for waders like turnstones, sanderlings and redshanks.

As the old saying goes, 'it's an ill wind that blows nobody any good'.

Condemned to life in total darkness beneath the Stadium of Light

I found these two photos amongst colour transparencies that I took back in 1994. They are of a little gammarid shrimp, similar to the species that live in ponds and streams everywhere, but this one has a very unusual story attached to it.

One day in late spring 1994, just before Monkwearmouth colliery, also known as Wearmouth colliery (see photos here), was due to close, I had a telephone call from a journalist on the Northern Echo who had been talking to some of the miners who were about to be made redundant. This was more than just another pit closure: Monkwearmouth was the last deep mine to close in the Durham coalfield and had been there for 178 years. It had once been the deepest coal mine in the world.

The miners told a story about shrimps that lived in pools of water at the bottom of the mine. The crustaceans had most likely been taken down there in water for the pit ponies and were well known to miners who had worked the seams in  the oldest shafts. 

At that time the deepest hole in the ground I've ever been down was at Cheddar caves, so the offer of a trip down to the bottom of the mine to collect some shrimps was too good to miss. At the bottom of the old shaft that had been abandoned for many years we found the shrimps living in the coal dust in pools of water, where they most probably fed on bacteria that lived on sulphur and fungi that lived on rotting wood. If you look at the photos above you can see grey coal dust in their digestive tracts. They had an aversion to light and when the beam of our helmet lamps fell on them they scuttled down into coal dust slurry. If you look at the enlargement of the eye (below) you can see that it had only a few, rather disorganised lenses, compared with a crustacean that lives in daylight like this one - these troglodyte shrimps may have been on their way to losing their redundant power of sight. 

We brought a couple of buckets of them up to the surface and kept them in a tank in my laboratory at Durham University. We had hoped to go back for more but British Coal demolished the winding tower with indecent haste before we could mount another expedition.

 This is the piece about the collecting trip that I wrote at the time for the Guardian Country Diary:

We entered the rusty cage of B Pit at Monkwearmouth colliery on a rescue mission, in search of an underground colony of shrimps that has persisted there since the shaft was opened in 1841. After a 12-minute descent we jerked to a halt 1080 feet underground, stepping out into caverns lined with crystals that glistened in our lamp beams. 

We found the colony, in a small black lagoon at a tunnel entrance littered with rusty picks and blocked by a collapsed roof. The half-inch-long shrimps dashed across the surface, thrashing through pools of light from our helmets and disappearing into the black ooze. These tiny crustaceans, familiar to generations of miners, live in a seasonless world of perpetual darkness and constant temperature, probably feeding on bacteria that grow on sulphur in the coal. Kenny Drysdale, the shaftsman who led us to them, told us that miners once supplemented the shrimp' diet with bread crusts. Within a few minutes we had scooped up as many animals as we could catch. The only other sign of life was a spider's web. Its builder, long since gone, must have been drawn down by the shaft ventilation system. 

In the tunnels we passed massive, rusty iron grates where controlled fires had once burned, to draw in cold air from above in the wake of their rising column of heat. Then, this pit must have resembled a scene from the underworld. The names of generations of miners were chalked or scratched on walls and beams in silent tunnels strewn with rusty pulleys and rails, thick with dust, shored up by props and baulks and boards and sealed with doors that hung from creaking hinges. 

Back on the surface, the rescued shrimps now live in my laboratory, thriving in an aquarium. Soon the unlucky ones will be sealed underground for ever, when the life of the colliery finally expires. Yesterday, I dropped a crust of bread in the tank. The shrimps swarmed around, tore crumbs off and retreated to their corners, just as Kenny said they would.

June 1994.

There's a rather sad postscript, which leaves me with an abiding sense of guilt. Soon after we brought the shrimps up our new laboratories at Durham University were completed and we had to move out of the old ones in a tearing hurry so that builders could move in. The shrimp tanks were due to be the last items to be moved but somehow someone mistook the tanks of grey water and coal slurry for rubbish to be disposed of, and tipped the water down the drain and threw the old tanks in the skip. So all that remains are a few specimens preserved in alcohol and, perhaps, the descendants of some that I had released into our garden pond.

Almost as soon as the pit was demolished and the site was cleared work began on  Sunderland Football Club's new Stadium of Light on the surface, immediately above. The population of shrimps is still down there, 1000 feet underground, nibbling away at fungi growing on rotting pit props and feeding on the sulphur bacteria, and will now remain there, in total darkness, for all eternity.

Gold

Whoever is responsible for planting this fabulous display, in what has always been a rather dull patch of grassland on the low cliffs between Seaburn and Whitburn, near Sunderland, deserves to be congratulated. There is cornflowers, corn poppies, corn chamomile and corn marigold in the mixture but its the last of these that predominated in today's sunshine. 

The wild flowers have been sown in a broad strip around the field, leaving the grassy centre for the seabirds to roost and feed on at high tide. 

Just about everyone who walked past today stopped to take a photograph.

Corn marigold Chrysanthemum segetum, also known in some parts of the country as 'gold', was once a very common cornfield weed but has been eliminated from most agricultural land by the intensive use of herbicides. It does have a persistent seed bank in the soil because the seeds have a long viability period, and I have seen it grow naturally near Durham city in disturbed soil, long before it was a fashionable component of cornfield wild flower seed mixtures like the one that would have been used for this display.

The flower is an excellent source of pollen for late summer insects like hoverflies and when it's sown in the way that it's been used here it produces a stop-you-in- your-tracks display. Good for wildlife, good for people and, I suspect, a very economical way to produce a wonderful floral display at minimum cost to the local council taxpayer.

For a couple more examples of deliberately planted wild flower displays, click here and here.

Britain's Largest Woodlouse and a dozy seal

Today's Guardian Country Diary describes encounters with two very interesting animals during a stroll on Roker Pier at Sunderland. Here's the pier, below, on a calm, sunny day.

This sea slater Ligia oceanica had crawled out of a crack between the stone blocks on the pier. They usually do most of their feeding at dusk, grazing on algae, and you don't often see them in the open in broad daylight. This is Britain's largest woodlouse species and it's confined to areas just above the high water mark on the seashore. The coin is a 10 pence piece, 25mm. in diameter, so you can get an idea of the animal's size - about four times larger than a garden woodlouse.

These little animals are very well camouflaged, especially when they hunker down so that the skirts of their armour plates are pressed close to the ground and they cast no shadow. It matched the stone so well that it was very lucky that I didn't tread on it.

The most remarkable thing about sea slaters is the ease and speed with which they change colour, due to being able to expand and contract pigment spots in their cuticle, so that they match their background. This is the same animal as the one on the grey stone, after it had been kept on a white background in bright sunlight for a few minutes. The pigment spots have contracted and it's almost translucent.

Sea slaters have large eyes for a woodlouse, perhaps because they do most of their feeding at dusk.

The sea slaters that live between the granite blocks here are often pummelled by waves that break over the pier (see picture below) but can maintain a tenacious grip on the stone with those needle-sharp bristles on the tip of their legs. Their flattened shape is perfect for squeezing into the gaps between the stone blocks.

You can see the jaws quite nicely here, and also the pigment spots in the body armour, fully contracted so they are just small brown dots.

We might have missed this character too if it hadn't raised a flipper to have a scratch. It was sunbathing on Roker beach below the pier and its smooth outline and mottled colouring made it surprisingly inconspicuous against the sand and rocks at low tide. I wonder if seals dream when they are asleep? If so, then it's probably having a very satisfying fantasy about pursuing fat, succulent salmon.

I'd guess that this grey seal must have been born on the Farne Islands last autumn. It had been left high up on Roker beach by an extremely high equinoctial spring tide. It didn't seem to be at all concerned and was content to bask in the sun and wait for the tide to return.  

Lovely animal, isn't it?

This is Roker pier a week later. Somewhere between the granite blocks, under the waves, there'll be sea slaters hunkered down. As for the seal, that'll be somewhere out to sea.

A walk along the promenade

Today's Guardian Country Diary describes a visit to the coast just north of the mouth of the river Wear at Sunderland. 

Roker pier, at the mouth of the river, is a good place to watch turnstones that hang around waiting to pick up tit-bits that anglers on the pier drop when they re-bait their hooks. These birds have become remarkably tame, unlike their conspecifics a little further along the coast (see below) that are far more wary.

The first hint of a fishing line being reeled in and food becoming available and the turnstones close in ....

A little further along the coast, at Cannonball Rocks, there's a promenade cafe where you can get more than a splash of milk in your cup of tea if you're not careful, but it's a sunny, sheltered spot to sit and watch shipping entering and leaving the harbour....

.... and to warm your hands around a mug of tea.

As soon as you get onto the promenade at Seaburn you meet these very attentive flocks of starlings .....

.... loitering around the benches, waiting for someone to chuck them a chip from their fish 'n' chips. There's a bit of a dependency culture developing amongst some bird species along this coast.

Our destination was Whitburn rocks, always a good place to watch waders as the rising tide pushes them further up the beach. This little group of sanderlings raced down the beach following every retreating wave, picking up invertebrates, .....

....then raced back again, just keeping ahead of boiling surf that threatened to engulf them

At this end of the promenade turnstones behave the way they are supposed to behave, flipping over seaweed and stones in their hunt for food.

The rich mottled brown plumage on their backs blends with the piles of wracks and kelps, providing ...

... excellent camouflage, in comparision to paler sanderlings that were forced to join them in the pools between the piles of seaweeds, while they waited for the tide to fall and expose their preferred sandy habitat again.

If you just sit on the shingle beach here and wait for the tide to push the sanderlings towards you they approach quite closely, but they move so fast that the closer they get, the harder they are to follow. Lovely little birds, though.

And finally, more free-loading birds - gulls following an inshore fishing boat as it heads out of the Wear into the North Sea on the flood tide.