page_title: Laduviken
section_title: Flora and fauna
hierarchical_section_title: Laduviken / Flora and fauna
caption_attribution_description: w:Laduviken, w:Djurgården, Stockholm, Sweden.
context_page_description: Laduviken is a lake in Norra Djurgården, a semi-rural area in north-eastern Stockholm, Sweden, forming part of the Royal National City Park. It is one of six lakes in Djurgården, the others being: Lillsjön, Uggleviken, Isbladskärret, Lappkärret, and Spegeldammen.
context_section_description: Presence of phytoplankton is low in August with exceptional blue green algae, green algae, and golden algae.  Occurrence of zooplankton is more varied with several species of rotifers, cladocerans, and copepods.  Among the aquatic plants in the lake fennel pondweed is notable as it normally only occurs in sea bays. Other aquatic plants and nymphoides include rigid hornwort, broad-leaved pondweed, perfoliate pondweed, water-starwort, Nymphaea alba, Lemna, and Chara tomentosa (for which the lake is, together with Kyrksjön, the only locale in Stockholm).
  The sparse fauna before the dredging of the lake, after 1995 evolved into a pretty considerable variety of species typical for shallow lakes rich in nutrients.  Two species of freshwater snails, Bithynia leachii and Gyraulus crista, were earlier considered as endangered.  Noteworthy is also the population of several freshwater mussels, duck mussel and swan mussel, and Hippeutis complanatus, the latter two declining.  A species of Oligochaeta new in Sweden has been reported in the lake just like did the rare hairy dragonfly.  An inventory of dragonfly larvae in 2000 unveiled several other species (mostly red-eyed damselfly but also common blue damselfly, azure damselfly, variable damselfly, and northern damselfly (Coenagrion hastulatum).  Fish population reflects the shortage of oxygen with an absence of carp bream and silver bream and an abundance of perch, roach, and crucian carp dating back to before the dredging.  The outlet forms a threshold for migrating species.
  Mallard and great crested grebe are breeding in the lake, just like are occasionally common moorhen and Canada goose (introduced in Sweden in the 1930s).  Marsh warbler and gray heron are often seen among the reed. Even though reed have been cleared to attract waders, as a locale for birs, the lake hasn't met expectations much due to neglected attention of the canals and islands.  There are three species of protected frogs in the lake: common frog, common toad, and smooth newt. The deers once abundant in the area have been superseded by roe deers.
caption: Water lilies
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