You are standing on the banks of the Lymbourne, flowing to the coast and containing South Downs rainfall from decades ago, filtered and purified through 100 million year old chalk beds.
Did You Know?
‘Bourne’is an Old English word for a seasonal stream. Bournes are often completely dry in the summer months but in full flow in winter, dependent on rainfall. Bourne was famously used by Shakespeare in “that undiscover’d country from whose bourne no traveller returns”
All chalk streams are valued habitats. Conservationists work to restore natural flow by adding trees on the river banks, as well as reducing barriers to river flow.
Did You Know?
Imagine the Bourne landscape as a layered cake with old chalk rock sandwiched between younger rocks like sands and clays above and older rocks like greensands below. If you tilt the cake and then run a cake slice across the raised edge this is a very simple version of what the landscape of southern England looks like!
A band of chalk is exposed at the surface with older rocks to the north and west at the foot of the steep scarp-face of the chalk, and younger rocks beyond the longer more gently inclined slope-face of the chalk.
Our region has over 175 of the world’s 200 rare chalk streams, supporting unique ecosystems, including varieties of stonefly, mayfly, trout and shrimps.
Biodiversity is the biological wealth of a region, at the habitat level and species level. Chalk streams have an abundance of biodiversity. What can you spot?
Plants
Comfrey, lesser celandine, germander speedwell and greater stitchwort.
Butterflies
Brimstone, peacock, a small copper and a small skipper butterfly.
Moths
Angle, Rosy footman, Six-striped rustic and a Figure-of-eighty moth.
Mammals
A fox, grey squirrel, wood mouse and badgers.
Birds
A female blackbird, robin, green woodpecker and a wood pigeon.
Reptiles and amphibians
A common frog, a slow worm, a smooth newt and a common toad.
Grasshoppers and crickets
Earwig, a dusky cockroach, field grasshopper and oak bush cricket.
Bees and wasps
Common wasp, honey bee, red banded sand wasp and a queen hornet.
Beetles
Stag beetle, hazel leaf roller, summer chafers and wasp beetles.
Dragonflies
Emperor, common blue damselfly, large red damselfly and broad-bodied chaser.
Flies
Beefly, hoverfly, narcissus fly and robberfly.
Spiders
Male Amaurobius ferox, crab spider, green Areniella cucurbitina and wasp spider.
Other Invertebrates
Flat-backed millipede, woodlouse, small blind white woodlouse and a centipede.
- Read more about the Hampshire Bournes – click here
- Read more about the chalk streams of Hampshire – click here
- Read about chalk rivers at the Wildlife Trusts – click here