četvrtak, 16. rujna 2010.

Lake Tanganyika

Lake Tanganyika, the domain of Cyphotilapia frontosa.  Africa has been home to this lake long before man walked the Earth, much longer.   Scientists estimate Lake Tanganyika’s age between 9 to 12 million years.  At more than 4700 feet it’s considered the second deepest lake in the world. To give some perspective on how deep that is, imagine the Sears Tower stacked on top of itself almost three times! However the water contains no oxygen past a depth of 770 feet in the south and 350 feet in the north.  Its length is 420 miles, a bit longer than the distance from Chicago to Pittsburgh. Its width is 45 miles at its widest point. Almost 1/6 of the world’s freshwater is contained in Lake Tanganyika.
Lake Tanganyika from space

Four countries surround Lake Tanganyika, Burundi on the northeast, Tanzania on the East, Zambia on the south, and Congo (formally Zaire) on the west.
The mineral content of the lake is extremely high. It is so high that it precipitates and forms underwater flows that coat the rocks. The lake has been measured at pH values above 9.0. If the water in your aquarium is above 7.0, this will be satisfactory. Frontosa and other tanganyikan cichlids seem to adapt well as long as you are above this level.
The temperature of the water varies only about 6 degrees Fahrenheit from the surface to 3000 feet and experiences no yearly turnover like many lakes. Temperature from 130 feet to 320 feet is approximately 76 degrees Fahrenheit. This is probably the perfect temperature of the Frontosa tank. Since fry are usually found shallower, 78 degrees for them would probably be better.
Lake Tanganyika contains three major basins which all formed separately and joined when their waters rose over time. All rivers except one, the Lukuga flow into the lake. 95 percent of the water lost from the lake is through evaporation.
Freshwater jellyfish in Lake TanganyikaThe most successful family of fish in Lake Tanganyika, the Cichlidae, has about two hundred species and all except a few are found only there (endemic). Frontosa are, of course, a member of this family. The lake also contains one of the only freshwater jellyfish, numerous mollusks, sponges, and aquatic snakes that are endemic as well.
Lake Tanganyika Fishery Resources provide employment and food directly for more than 40,000 fishermen and their families. Indirectly, more than 20 million people have access to the natural resources, fish and water, of the lake which also facilitates transport and communications.
Traditional fishermen using scoop nets and beach seines, the advanced fishermen using catamaran liftnets, as well as the decreasing industrial sector using purse seines, all have the two clupeids (S. tanganyicae. L. miodon) and the predatory nile-perchs (mostly L. stappersii) as their target species.   Cichlids are caught and eaten, but are not the main prey of the fishermen.
School of Tropheus in Lake TanganyikaFebruary through April are the rainy months for the lake. Water visibility is probably at its worst during this time. June through August has the coolest air temperature. The lake becomes clearer but occasional algae blooms may occur. September through November is a good time for lake visibility (one of the clearest lakes in the world!), but the air temperature is extremely hot. Since Lake Tanganyika is just south of the Equator, the longest days occur in December-January. The one thing that surprises you when you are near the equator is though it is extremely hot, the summer days do not compare in length to those in the temperate zones

Nema komentara:

Objavi komentar