The Tamar–Tavy Estuary is a

Site of Special Scientific Interest A Site of Special Scientific Interest (SSSI) in Great Britain, or an Area of Special Scientific Interest (ASSI) in the Isle of Man and Northern Ireland, is a conservation designation denoting a protected area in the United Kingdom and Isle ...

(SSSI) covering the tidal

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...

of the

River Tamar The Tamar (; ) is a river in south west England that forms most of the border between Devon (to the east) and Cornwall (to the west). A large part of the valley of the Tamar is protected as the Tamar Valley National Landscape (an Area of Outsta ...

and the

River Tavy The Tavy () is a river on Dartmoor, Devon, England. The name derives from the Brythonic languages, Brythonic root , once thought to mean 'dark' but now generally understood to mean 'to flow'. It has given its name to the town of Tavistock and ...

on the border between

Cornwall Cornwall (; or ) is a Ceremonial counties of England, ceremonial county in South West England. It is also one of the Celtic nations and the homeland of the Cornish people. The county is bordered by the Atlantic Ocean to the north and west, ...

and

Devon Devon ( ; historically also known as Devonshire , ) is a ceremonial county in South West England. It is bordered by the Bristol Channel to the north, Somerset and Dorset to the east, the English Channel to the south, and Cornwall to the west ...

in England, UK. Parts of the land designated as the Tamar–Tavy Estuary SSSI are owned by the

National Trust The National Trust () is a heritage and nature conservation charity and membership organisation in England, Wales and Northern Ireland. The Trust was founded in 1895 by Octavia Hill, Sir Robert Hunter and Hardwicke Rawnsley to "promote the ...

and parts are owned by the

Ministry of Defence A ministry of defence or defense (see American and British English spelling differences#-ce.2C -se, spelling differences), also known as a department of defence or defense, is the part of a government responsible for matters of defence and Mi ...

and the

Diocese of Truro The Diocese of Truro (established 1876) is a Church of England diocese in the Province of Canterbury which covers Cornwall, the Isles of Scilly and a small part of Devon. The bishop's seat is at Truro Cathedral. Geography and history The d ...

also owns land in this SSSI. Part of the Tamar estuary also forms the Tamar Estuary Nature Reserve, owned by the

Cornwall Wildlife Trust The Cornwall Wildlife Trust (founded as the Cornwall Naturalists' Club) is a charitable organisation founded in 1962 that is concerned solely with Cornwall, England, United Kingdom. It deals with the conservation and preservation of Cornwall's w ...

. The site was designated in 1991 for its biodiversity and varying habitats that support many

wader 245px, A flock of Red_knot.html" ;"title="Dunlins and Red knot">Dunlins and Red knots Waders or shorebirds are birds of the order Charadriiformes commonly found wikt:wade#Etymology 1, wading along shorelines and mudflats in order to foraging, ...

and

wildfowl The Anatidae are the biological family of water birds that includes ducks, geese, and swans. The family has a cosmopolitan distribution, occurring on all the world's continents except Antarctica. These birds are adapted for swimming, floating o ...

species, as well as the special interest of its marine biology.

Geography

The SSSI encompasses the entirety of the tidal regions of the Tamar; from

Gunnislake Gunnislake () is a large village in east Cornwall, England, United Kingdom. It is situated in the Tamar Valley approximately north of Plymouth The first woman cabinet minister in the British Empire, Mary Ellen Smith, was born here in 1863. G ...

down to the

Tamar Bridge The Tamar Bridge is a suspension bridge over the River Tamar between Saltash, Cornwall and Plymouth, Devon in southwest England. It is long, running adjacent the Royal Albert Bridge, and part of the A38, a main road between the two counties. ...

in the south, where it forms the Hamoaze, and the River Tavy from Lopwell to its discharge in the Tamar. The site also includes Kingsmill Lake, Tamerton Lake and a few other tributary streams of the Tamar, as well as the marshes around

Morwellham Quay Morwellham Quay is an historic river port in Devon, England that developed to support the local mines. The port had its peak in the Victorian era and is now run as a tourist attraction and museum. It is the terminus of the Tavistock Canal, and ...

. The site forms part of the ''Tamar Estuaries Complex''

Special Protection Area A special protection area (SPA) is a designation under the European Union Directive on the Conservation of Wild Birds. Under the Directive, Member States of the European Union (EU) have a duty to safeguard the habitats of migratory birds and cer ...

(SPA), along with the estuary of the River Lynher and St John's Lake, as well as forming part of the ''

Plymouth Sound Plymouth Sound, or locally just The Sound, is a deep inlet or sound in the English Channel near Plymouth in England. Description Its southwest and southeast corners are Penlee Point in Cornwall and Wembury Point in Devon, a distance of abo ...

and Estuaries''

Special Area of Conservation A special area of conservation (SAC) is defined in the European Union's Habitats Directive (92/43/EEC), also known as the ''Directive on the Conservation of Natural Habitats and of Wild Fauna and Flora''. They are to protect the 220 habitats and ap ...

(SAC). The Cornwall Wildlife Trust owns the Tamar Estuary

nature reserve A nature reserve (also known as a wildlife refuge, wildlife sanctuary, biosphere reserve or bioreserve, natural or nature preserve, or nature conservation area) is a protected area of importance for flora, fauna, funga, or features of geologic ...

around Kingsmill Lake, below Landulph,Ordnance Survey: Explorer map sheet 108 ''Lower Tamar Valley & Plymouth'' and Lopwell Dam is a Local Nature Reserve, covering the dam and surrounding woodlands.

Wildlife and ecology

The SSSI, due to its habitats, is of international importance for

nature conservation Nature conservation is the ethic/moral philosophy and conservation movement focused on protecting species from extinction, maintaining and restoring habitats, enhancing ecosystem services, and protecting biological diversity. A range of values ...

, in particular as a wintering site for wildfowl and wader birds.

Mudflat Mudflats or mud flats, also known as tidal flats or, in Ireland, slob or slobs, are coastal wetlands that form in intertidal areas where sediments have been deposited by tides or rivers. A global analysis published in 2019 suggested that tidal ...

s form the lower reaches of the estuary system and are bordered by

salt marsh A salt marsh, saltmarsh or salting, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides. I ...

, inundation grassland and rocky shoreline habitats. These mainly contain common saltmarsh-grass (''

Puccinellia maritima ''Puccinellia maritima'' is a species of grass Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, ...

''),

red fescue ''Festuca rubra'' is a species of grass known by the common name red fescue, creeping red fescue or the rush-leaf fescue. It is widespread across much of the Northern Hemisphere and can tolerate many habitats and climates. It is best adapted to w ...

and sea couch, as well as two nationally scarce species of grass: stiff saltmarsh-grass ('' Puccinellia rupestris'') and bulbous foxtail. The upstream part of the system supports freshwater marsh,

fen A fen is a type of peat-accumulating wetland fed by mineral-rich ground or surface water. It is one of the main types of wetland along with marshes, swamps, and bogs. Bogs and fens, both peat-forming ecosystems, are also known as mires ...

, rush pasture and reedmarsh habitats, along with wooded valleys in places. Species include the

common reed ''Phragmites australis'', known as the common reed, is a species of flowering plant in the grass family Poaceae. It is a wetland grass that can grow up to tall and has a cosmopolitan distribution worldwide. Description ''Phragmites australis' ...

and the only known population in the

British Isles The British Isles are an archipelago in the Atlantic Ocean, North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner Hebrides, Inner and Outer Hebr ...

of triangular club-rush, part of the genus ''

Schoenoplectus ''Schoenoplectus'' (club-rush ld World species bulrush or tule ew World species is a genus of plants in the Cyperaceae, sedge family with a cosmopolitan distribution. Note that the name bulrush is also applied to species in the unrelated ...

''. The mudflats attract more than 20% of the British wintering population of the uncommon

pied avocet The pied avocet (''Recurvirostra avosetta'') is a large black and white wader in the avocet and stilt family, Recurvirostridae. They breed in temperate Europe and across the Palearctic to Central Asia then on to the Russian Far East. It is a m ...

. They additionally support

black-tailed godwit The black-tailed godwit (''Limosa limosa'') is a large, long-legged, long-billed shorebird first described by Carl Linnaeus in 1758. It is a member of the godwit genus, '' Limosa''. There are four subspecies, all with orange head, neck and ches ...

common redshank The common redshank or simply redshank (''Tringa totanus'') is a Eurasian wader in the large family Scolopacidae. Taxonomy The common redshank was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of hi ...

dunlin The dunlin (''Calidris alpina'') is a small wader in the genus '' Calidris''. The English name is a dialect form of "dunling", first recorded in 1531–1532. It derives from ''dun'', "dull brown", with the suffix ''-ling'', meaning a person or ...

, whimbrel, greenshank,

spotted redshank The spotted redshank (''Tringa erythropus'') is a wader (shorebird) in the large bird family Scolopacidae. The genus name ''Tringa'' is the Neo-Latin name given to the green sandpiper by Aldrovandus in 1599 based on Ancient Greek ''trungas'', a ...

and

green sandpiper The green sandpiper (''Tringa ochropus'') is a small wader (shorebird) of the Old World. The green sandpiper represents an ancient lineage of the genus ''Tringa''; its only close living relative is the solitary sandpiper (''T. solitaria''). The ...

during the wintering period, with the first birds arriving in October and leaving again throughout March. The highly variable salinity along the transition from marine estuary to river allows for a diverse marine culture. Seaweeds,

green algae The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ...

and communities of

polychaete worm Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are ma ...

s are all found in the estuary system; near

Calstock Calstock () is a civil parishes in England, civil parish and a large village in south east Cornwall, England, United Kingdom, on the border with Devon. The village is situated on the River Tamar south west of Tavistock, Devon, Tavistock and no ...

is found the shrimp '' Palaemon longirostris'', which has been recorded in only two other estuaries in Britain. The estuary is also one of only two sites in the UK where the fish,

allis shad The allis shad (''Alosa alosa'') is a widespread Northeast Atlantic species of fish in the Alosidae, Alosidae family. It is an Fish migration, anadromous fish which migrates into fresh water to spawn. It is found in the eastern Atlantic Ocean, ...

, spawn. Other larger animals found in undisturbed parts of the SSSI include the

European otter The Eurasian otter (''Lutra lutra''), also known as the European otter, Eurasian river otter, European river otter, common otter, and Old World otter, is a semiaquatic mammal native to Eurasia and the Maghreb. The most widely distributed member o ...

, the

common kingfisher The common kingfisher (''Alcedo atthis''), also known as the Eurasian kingfisher and river kingfisher, is a small kingfisher with seven subspecies recognized within its wide distribution across Eurasia and North Africa. It is resident in much of ...

and

dormice A dormouse is a rodent of the family (biology), family Gliridae (this family is also variously called Myoxidae or Muscardinidae by different taxonomists). Dormice are nocturnal animals found in Africa, Asia, and Europe. They are named for their ...

Gallery

Image:River Tamar from Calstock Viaduct - geograph.org.uk - 73430.jpg, River Tamar from

Calstock Viaduct Calstock () is a civil parish and a large village in south east Cornwall, England, United Kingdom, on the border with Devon. The village is situated on the River Tamar south west of Tavistock and north of Plymouth. The parish had a population ...

File:River Tamar - geograph.org.uk - 326342.jpg, Mudflats and salt marshes on the lower reaches of the estuary system File:Salt marsh on the bank of the River Tamar - geograph.org.uk - 469684.jpg, Salt marsh on a lower bank of the River Tamar File:River Tamar from Cotehele Quay - geograph.org.uk - 196017.jpg, A reedmarsh on the upper reaches of the Tamar, at

Cotehele Cotehele is a medieval house with Tudor additions, situated in the parish of Calstock in the east of Cornwall, England, and now belonging to the National Trust. It is a rambling granite and slate-stone manor house on the banks of the River T ...

File:Lopwell Dam - geograph.org.uk - 84226.jpg, The Lopwell Dam, a

weir A weir or low-head dam is a barrier across the width of a river that alters the flow characteristics of water and usually results in a change in the height of the water level. Weirs are also used to control the flow of water for outlets of l ...

that is the tidal limit of the River Tavy

References

External links

* {{DEFAULTSORT:Tamar-Tavy Estuary Sites of Special Scientific Interest in Cornwall Sites of Special Scientific Interest in Devon Sites of Special Scientific Interest notified in 1991 Special Protection Areas in England Nature reserves of the Cornwall Wildlife Trust Estuaries of England River Tamar Cornish coast