Visit to a tropical coral reef

Bollihope, just south of Frosterley in Weardale, can be a bleak place at this time of year. Acres of brown heather and withered bracken, with a few small conifer plantations. But if you follow some of the burns that flow down into the bottom of the valley you soon find yourself standing on a tropical coral reef, albeit a 325 million year-old one.

This is the subject of Thursday's Guardian Country Diary

This is the rock known as Frosterley marble, which is not a true marble at all but a fine grained, dark limestone full of fossil Dibunophyllum bipartitum coral. In this slab you can see one almost complete piece of the horn-shaped coral in longitudinal section and two pieces in transverse section. The contrast between the fossil and the stone matrix becomes much greater when you make it wet or polish the surface. 

The state of preservation of the coral structure is astonishing.  This particular specimen is embedded in a slab that must have once been a small waterfall until the burn changed course. It has been worn smooth by flowing water.

Medieval craftsmen spent months cutting and polishing the rock by hand to achieve a smooth, marble like black surface that revealed the fossils in this detail. Their work can be seen in pillars of the Chapel of the Nine Altars in Durham cathedral and in the pillars in the Bishops' Palace at Auckland castle in Bishop Auckland, as well as in smaller objects like the font in Frosterley church. 

It's also in the flagstones on the floor of the bar of the Black Bull pub in Frosterley.

Frosterley marble floor decoration in the Laing Art Gallery, Newcastle-upon-Tyne

Cold-Blooded and Spineless

Last Friday saw the launch of the North Pennines Area of Outstanding Natural Beauty Cold-Blooded and Spineless project. Over the next five years it will train volunteers and local wildlife groups to identify and map the distribution of invertebrate animals in the AONB, as well as working with schools and artists to encourage them to appreciate and celebrate the wealth of  smaller elements in the wildlife of the region.

You can read much more about the project at http://www.northpennines.org.uk/Pages/Cold-bloodedandSpineless.aspx

After the various presentations at the launch, held at the Environmental Centre at Harehope Quarry near Frosterley in Weardale, we went on a short bug hunt. Predictably, there weren't many flying insects about in mid-March, although someone did catch this male mosquito with rather magnificent antennae.

But when we started turning over stones it was a different story.

Lots of ants

A common pygmy woodlouse Trichoniscus pusillus

I think this one is a young specimen of the common shiny woodlouse Oniscus asellus

Lots of black snake millipedes Tachypodoiulus niger

More millipedes, that I've yet to identify

Two very small snails, awaiting identification

Several species of springtail. In the picture above, showing the underside, you can see the forked furca folded under the tail, that it uses like a pole-vaulter's pole to catapult itself into the air.

Click here for more about springtails

A very fine devil's coach horse, with a formidable pair of needle-sharp jaws

Click here for more about devil's coach horses

Numerous ground beetles, including ....

..... this one that played possum when it was turned onto its back, and ... 

.... this one, that was carrying a hitch-hiker on its back, which ...

... looks like it might be a very small tick.

I haven't had time to ID these properly yet, but am posting them now so that those who found them can download the pictures.

It's amazing what you can find if a dozen people spend half an hour turning over stones, even if it is a cold March afternoon!

If you'd like to know more about the Cold-blooded and Spineless project, or would like to become involved, contact samantha@northpenninesaonb.org.uk