Editing Brackish water (section)

=== Brackish seas and lakes ===
{{See also|Salt lake}}
Some seas and lakes are brackish. The [[Baltic Sea]] is a brackish sea adjoining the [[North Sea]]. Originally the [[Eridanos (geology)|Eridanos]] river system prior to the [[Pleistocene]], since then it has been flooded by the North Sea but still receives so much freshwater from the adjacent lands that the water is brackish. As [[seawater]] is denser, the water in the Baltic is stratified, with seawater at the bottom and freshwater at the top. Limited mixing occurs because of the lack of tides and storms, with the result that the fish fauna at the surface is freshwater in composition while that lower down is more marine. [[Cod]] are an example of a species only found in deep water in the Baltic, while [[Northern pike|pike]] are confined to the less saline surface waters.

The [[Caspian Sea]] is the world's largest lake and contains brackish water with a salinity about one-third that of normal seawater. The Caspian is famous for its peculiar animal fauna, including one of the few non-marine seals (the [[Caspian seal]]) and the great [[sturgeon]]s, a major source of [[caviar]].

[[Hudson Bay]] is a brackish [[marginal sea]] of the [[Arctic Ocean]], it remains brackish due its limited connections to the open ocean, very high levels freshwater [[surface runoff]] input from the large [[Hudson Bay drainage basin]], and low rate of evaporation due to being completely covered in ice for over half the year.

In the [[Black Sea]] the surface water is brackish with an average salinity of about 17–18 parts per thousand compared to 30 to 40 for the oceans.<ref name="Lüning 1991 p.121">{{cite book |last=Lüning |first=Klaus |title=Seaweeds: Their Environment, Biogeography, and Ecophysiology |publisher=John Wiley & Sons |date=1991-01-16 |isbn=978-0-471-62434-9 |ol=7619451M |page=121}}</ref> The deep, [[anoxic event|anoxic]] water of the Black Sea originates from warm, salty water of the [[Mediterranean]].

[[Lake Texoma]], a reservoir on the border between the U.S. states of [[Texas]] and [[Oklahoma]], is a rare example of a brackish lake that is neither part of an [[endorheic basin]] nor a direct arm of the ocean, though its salinity is considerably lower than that of the other bodies of water mentioned here. The reservoir was created by the damming of the [[Red River of the South]], which (along with several of its tributaries) receives large amounts of salt from natural seepage from buried deposits in the upstream region. The salinity is high enough that [[striped bass]], a fish normally found only in salt water, has self-sustaining populations in the lake.<ref>Malewitz, Jim (21 November 2013).  [https://www.texastribune.org/2013/11/21/along-salty-red-river-communities-seek-feds-help/ "Communities Along Red River Seek Feds' Help."] ''The Texas Tribune''. Retrieved 25 December 2018.</ref><ref>[https://pubs.usgs.gov/fs/fs-170-97/FS_170-97.htm U.S. Geological Survey Fact Sheet 170-97]. Retrieved 25 December 2018.</ref>