Earthwatch volunteers have helped discover many new biological species and archaeological finds, but now they can add a geographic feature, a small lake, to their list of achievements. In September, volunteers on Earthwatch's Lakes of the Rift Valley project reached a fresh water lake in central Kenya that is, as yet, unknown to science.

The lake covers 3-4 square kilometers and is situated in a dense marsh near Lake Baringo, one of the study sites for Lakes of the Rift Valley. The small lake is believed to have formed in the mid or late 1990s, possibly due to heavy El Niño rains, and was already known by local villagers, who referred to it as Kichiritith. Difficulties of access have ensured that it has remained undisturbed and pristine. This is in contrast to Lake Baringo and nearby Lake Naivasha, which are both beset by problems such as overfishing, the introduction of alien species, and the deterioration of water quality.

"We knew about the small lake last year, but we were not able to access it, and it wasn't then fully realized that it was indeed a proper lake", says Dr. Håkan Tarras-Wahlberg (Swedish Geological), a physical geographer and one of the principal investigators on Lakes of the Rift Valley. "It was not until I saw Lake Kichiritith from a viewpoint in some hills that I realized its potential significance: being protected by the dense marsh area, it could provide evidence for what the main lake once must have been like".

Earthwatch ornithologist Brooks Childress (University of Leicester and Wildfowl Trust UK) visited the swampy shores of Kichiritith in early 2001 when he prepared a first bird list for the area. This year, a team led by Dr. Mucai Muchiri (Moi University, Kenya) and Tarras-Wahlberg became the first to get onto the lake itself and to describe it scientifically.

The work was done during an expedition to Lake Baringo, a lake famous for its rich bird life and thriving hippo and crocodile populations. Baringo supports a local fishery and also represents a precious source of fresh water in an otherwise dry area. However, local irrigation and excessive grazing has made the lake shallow and turbid, and the aquatic ecosystem is impoverished. The new lake offers a valuable glimpse of Baringo's past.

Unlike the main lake, Kichiritith's water is clear, and supports a dense mat of aquatic plants, including water lilies, which are now almost totally missing from Baringo. Many of the fish-eating bird species that used to be common on the main lake (e.g. herons, cormorants), thrive on Kichiritith. The microscopic life tells a similar story: whereas the small lake supports a rich and varied plankton community, Baringo is dominated one single specie of blue green algae - a tell tale sign of a system under stress.

"The new lake is exciting for two reasons," said Tarras-Wahlberg. "First, it is new to science. Second, and more importantly, its ecosystem is undisturbed and finely balanced. It can therefore provide a control, against which the changes that have occurred in the other fresh water lakes of the Rift Valley may be compared and assessed."

Teams on Lakes of the Rift Valley will return to Kichiritith next year, with the hope of collecting data that will help in the evaluation and restoration of neighboring lakes. The project, led by Dr. David Harper (University of Leicester) for the last 14 years, has led to tremendous gains in the understanding and management of Rift Valley lake ecology. Earthwatch-supported research here has generated more than 50 scientific publications and contributed to the recognition of Lake Naivasha as a RAMSAR site, or wetland of international significance. Since 2000, teams have moved to lakes Baringo and Bogoria, now also RAMSAR sites, to aid restoration and sustainable management there.

For information on volunteering on the Lakes of the Rift Valley project, click here.


Earthwatch Institute is an international nonprofit organization which supports scientific field research worldwide by offering members of the public unique opportunities to work alongside leading field scientists and researchers. The Institute's mission is to engage people worldwide in scientific field research and education to promote the understanding and action necessary for a sustainable environment.