Facts About Lake Malawi

About 2 million years ago, a masive increase in volcanic activity and shifting of the earth's surface resulted in the formation of the African rift valleys. It was within these rifts that the great lakes were formed. Lake Malawi is situated in the southern part of what is known as the Eastern Rift and is the ninth largest lake in the world.

Lake Malawi, along with Lake Tanganyika and Lake Victoria are referred to as Africa's Rift lakes. Over the course of these millions of years, Africa is being torn apart by geological forces - the lakes are like the perforations along which the continent is being ripped in two.

Lake Malawi is 600 km (380 miles) long and on some places 80 km (50 miles) wide. It has a maximum depth of 700 m.. The largest proportion of the lake belongs to the state of Malawi, the NE part belongs to Tanzania and the East coast is ruled by Mozambique. The two most significant islands are Likoma and Chizumulu.

When Dr. Livingstone first discovered the lake, the native population called it "Nyasa" so he decided to name it "Lake Nyasa". Some time later he found that nyasa actually means lake so the name soon changed to "Lake Malawi" as we know it today. The lake is very important to the natives. Thousands of tons of fish are caught annually which provide the population with a protein rich food.

One of the features of the lake, and one that is very important as far as aquarists are concerned is the alkalinity of the water. Aquarists are used to pH values around the neutral point or slightly acid for most of the species of fish kept, however lake Malawi has pH values well above neutral, being measured at between 7.7 ° and 8.6°.

Lake Malawi is in a state of more or less permanent stratification: the lower layers have been depleted of oxygen and therefore are unsuitable for the fishes. Most cichlids do not inhabit depths of more than 50 metres.
The SE-wind (the Mwera), that blows mostly during the dry season, causes the colder layers to slightly rise and so temperatures lower to 20 °C (68 °F). During rainy season the temperature can rise to 30 °C (86 °F).

Due to the changes in temperatures and evaporation of the water the visibility underwater varies from between 1m to 20m.

Most of the lake's shoreline is very rocky but there are certain areas that are sandy or have vegetation. Swampland and marshy areas can also be found but most of the more colourful species of cichlid are found in the rocky areas where they are much more difficult to capture.

There's no lake in the world that contains more species of Cichlids than lake Malawi, it contains over 700 species of cichlid and only forty-odd species of non-cichlid fishes. What is so unusual about these species is that there are almost all endemic to this lake. An endemic species is one that is found in a particular (usually limited) geographical area and no other place in the world.