Lilla Värtan ( sv, Smaller Värtan) or simply Värtan is a

strait A strait is an oceanic landform connecting two seas or two other large areas of water. The surface water generally flows at the same elevation on both sides and through the strait in either direction. Most commonly, it is a narrow ocean channe ...

Stockholm Stockholm () is the Capital city, capital and List of urban areas in Sweden by population, largest city of Sweden as well as the List of urban areas in the Nordic countries, largest urban area in Scandinavia. Approximately 980,000 people liv ...

Sweden Sweden, formally the Kingdom of Sweden,The United Nations Group of Experts on Geographical Names states that the country's formal name is the Kingdom of SwedenUNGEGN World Geographical Names, Sweden./ref> is a Nordic country located on ...

. Separating mainland Stockholm from the island and municipality

Lidingö Lidingö, also known in its definite form ''Lidingön'' and as ''Lidingölandet'', is an island in the inner Stockholm archipelago, northeast of Stockholm, Sweden. In 2010, the population of the Lidingö urban area on the island was 31,561. It is ...

, it stretches from Blockhusudden in the south to

Stora Värtan Stora Värtan is an inlet of the Baltic Sea located in the Stockholm archipelago north of the city of Stockholm, Sweden. It is bordered to the west by the municipalities of Täby and Danderyd, to the south by the municipality of Lidingö, to the ...

in the north, and is joined by the

Stocksundet Stocksundet is a strait in Stockholm County in Sweden. It connects the Edsviken sea inlet, to the west, with the Lilla Värtan strait and eventually the Baltic sea, to the east. The strait also forms the border between the suburb of Stocksund in Dan ...

mid-way. Two bridges, collectively called

Lidingöbron Lidingöbron (Swedish: "The Lidingö Bridge") is the name of two existing and two historical bridges across the strait of Lilla Värtan between the mainland Norra Djurgården at Ropsten, at the eastern part of Stockholm, and the island of Lidingö ...

("Lidingö Bridge") stretch over the strait. While most of the coasts surrounding the strait are occupied by industries and the ferry terminals and oil tanks in the harbour area of

Värtahamnen Värtahamnen is a port in Stockholm, Sweden. Värtahamnen and the adjacent Stockholm Free Port at Lilla Värtan is Stockholm's main port. Värtahamnen primarily serves passenger ferries for the shipping company Silja Line as well as freighters fo ...

, natural beaches are found in both the southern and the northern end of the strait and the strait forms part of the

Royal National City Park The Royal National City Park ( sv, Kungliga nationalstadsparken) is a national city park, established by the Riksdag in 1995, and located in the municipalities of Stockholm, Solna and Lidingö in Sweden. 1/ km²2/ Population per km² Gallery ...

. Most common fish species are Baltic

herring Herring are forage fish, mostly belonging to the family of Clupeidae. Herring often move in large schools around fishing banks and near the coast, found particularly in shallow, temperate waters of the North Pacific and North Atlantic Oceans, i ...

sea trout Sea trout is the common name usually applied to anadromous (sea-run) forms of brown trout (''Salmo trutta''), and is often referred to as ''Salmo trutta'' morpha ''trutta''. Other names for anadromous brown trout are sewin (Wales), peel or peal ...

, and

salmon Salmon () is the common name for several list of commercially important fish species, commercially important species of euryhaline ray-finned fish from the family (biology), family Salmonidae, which are native to tributary, tributaries of the ...

. Stationary predator fishes, e.g.

northern pike The northern pike (''Esox lucius'') is a species of carnivorous fish of the genus '' Esox'' (the pikes). They are typical of brackish and fresh waters of the Northern Hemisphere (''i.e.'' holarctic in distribution). They are known simply as a ...

and

perch Perch is a common name for fish of the genus ''Perca'', freshwater gamefish belonging to the family Percidae. The perch, of which three species occur in different geographical areas, lend their name to a large order of vertebrates: the Percif ...

, are exposed to raised levels of

mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...

. The area is considered an important wintering location for several birds species, including

swan Swans are birds of the family (biology), family Anatidae within the genus ''Cygnus''. The swans' closest relatives include the goose, geese and ducks. Swans are grouped with the closely related geese in the subfamily Anserinae where they form t ...

Eurasian coot The Eurasian coot (''Fulica atra''), also known as the common coot, or Australian coot, is a member of the rail and crake bird family, the Rallidae. It is found in Europe, Asia, Australia, New Zealand and parts of North Africa. It has a slaty-bla ...

common pochard The common pochard (; ''Aythya ferina'') is a medium-sized diving duck. The scientific name is derived from Greek '' aithuia'', an unidentified seabird mentioned by authors including Hesychius and Aristotle, and Latin ''ferina'', "wild game", f ...

tufted duck The tufted duck or tufted pochard (''Aythya fuligula'') is a small diving duck with a population of close to one million birds, found in northern Eurasia. The scientific name is derived from Ancient Greek '' aithuia'', an unidentified seabird ment ...

black-headed gull The black-headed gull (''Chroicocephalus ridibundus'') is a small gull that breeds in much of the Palearctic including Europe and also in coastal eastern Canada. Most of the population is migratory and winters further south, but some birds res ...

lesser black-backed gull The lesser black-backed gull (''Larus fuscus'') is a large gull that breeds on the Atlantic coasts of Europe. It is migratory, wintering from the British Isles south to West Africa. It has increased dramatically in North America, most common alo ...

gadwall The gadwall (''Mareca strepera'') is a common and widespread dabbling duck in the family Anatidae. Taxonomy The gadwall was first described by Carl Linnaeus in his landmark 1758 10th edition of ''Systema Naturae''. DNA studies have shown that ...

, and

common tern The common tern (''Sterna hirundo'') is a seabird in the family Laridae. This bird has a circumpolar distribution, its four subspecies breeding in temperate and subarctic regions of Europe, Asia and North America. It is strongly migratory ...

. The strait constitutes an important locale, especially ice-free winters, besides the lake

Isbladskärret Isbladskärret is a small lake on Djurgården, an island in central Stockholm, Sweden. The lake is much appreciated among bird-watchers, and, being part of the Royal National City Park, also carefully monitored by several organizations, including ...

Djurgården Djurgården ( or ) or, more officially, ''Kungliga Djurgården'' (), is an island in central Stockholm, Sweden. Djurgården is home to historical buildings and monuments, museums, galleries, the amusement park Gröna Lund, the open-air museum ...

. Vegetation on the shore lines of Lilla Värtan includes

alder Alders are trees comprising the genus ''Alnus'' in the birch family Betulaceae. The genus comprises about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few sp ...

purple loosestrife ''Lythrum salicaria'' or purple loosestrifeFlora of NW Europe''Lythrum salicaria'' is a flowering plant belonging to the family Lythraceae. It should not be confused with other plants sharing the name loosestrife that are members of the family P ...

common valerian Valerian (''Valeriana officinalis'', Caprifoliaceae) is a perennial plant, perennial flowering plant native to Europe and Asia. In the summer when the mature plant may have a height of , it bears sweetly scented pink or white flowers that attrac ...

, yellow loosestrife,

reed canary-grass ''Phalaris arundinacea'', or reed canary grass, is a tall, perennial bunchgrass that commonly forms extensive single-species stands along the margins of lakes and streams and in wet open areas, with a wide distribution in Europe, Asia, northern ...

tall fescue ''Festuca arundinacea'' ( syn., ''Schedonorus arundinaceus'' and ''Lolium arundinaceum'') is a species of grass commonly known as tall fescue. It is a cool-season perennial C3 species of bunchgrass native to Europe. It is an important forage gr ...

, lesser periwinkle, and giant knotweed. Levels of

heavy metals upright=1.2, Crystals of osmium, a heavy metal nearly twice as dense as lead">lead.html" ;"title="osmium, a heavy metal nearly twice as dense as lead">osmium, a heavy metal nearly twice as dense as lead Heavy metals are generally defined as ...

and

organic waste Biodegradable waste includes any organic matter in waste which can be broken down into carbon dioxide, water, methane or simple organic molecules by micro-organisms and other living things by composting, aerobic digestion, anaerobic digestion ...

are high in the bottom silt and nutrient levels high in the water. The level of

phosphorus Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Ear ...

was 29 µg/L in 2005.

References

Geography of Stockholm Straits of Sweden {{Stockholm-geo-stub

See also

References