Rift Valley Lakes in Peril
Kenya’s Rift Valley lakes may seem pristine, but their ecosystems are facing serious threats to their wellbeing.
Despite being listed as Kenya’s fourth Ramsar site in January 2002, Lake Baringo faces numerous threats, among them droughts, severe siltation due to soil erosion around the seasonal luggas (dry river beds) and overfishing.
In the case of Lake Naivasha, tourism and the wealth generated by the flower farms has spawned massive development. In addition, pesticides and fertilisers are seeping into the lake. Irrigation has further destabilised erratic water levels. The lake’s ecology has also been interfered with on a number of other occasions, notably with the introduction of foreign fish (for sports and commercial fisheries), crayfish, the South American coypu (an aquatic rodent that initially escaped from a fur farm) and various aquatic plants, including the dreaded water hyacinth.
For these reasons Naivasha has been the focus of conservation efforts and in 1995, after years of lobbying from the Lake Naivasha Riparian Association (LNRA), the lake was designated a Ramsar site, officially recognising it as a wetland of international importance. Besides educating the locals dependent on the lake about the environmental issues involved, the LNRA, Elsamere Conservation Centre (www.elsamere.com) and other organisations work to establish a code of conduct among the local growers that will maintain the lake’s biodiversity. Among the positive outcomes is that since 2007, all local businesses have been required to submit environmental-impact statements. But much remains to be done.
Flamingos & the Art of Standing on One Leg
From Lake Bogoria in Kenya to Lake Natron in northern Tanzania, it's the classic Rift Valley image: the flamingo, or, rather, the massed ranks of flamingos standing completely still on one leg. Why they do so has baffled scientists for decades.
Finally, a 2017 study found that this pose has a very strong scientific reason: flamingos, it seems, expend less energy by standing on one leg than they do standing on two. More specifically, flamingos do not actively use their muscles in any way in this one-legged position. Which is, of course, why flamingos can actually sleep while standing in this position. So easy and perfectly balanced is this pose that the scientists who carried out the study discovered that even dead flamingos could remain in this position on one leg (but not two legs) without any means of upright support!
Closer examination of the position reveals that the standing foot sits directly beneath the body, meaning that the leg angles inwards, thereby enabling the birds to assume the position and remain almost entirely motionless for significant periods.
Rift Valley Resources
- The Great Rift Valley: Being the Narrative of a Journey to Mount Kenya and Lake Baringo (1896), JW Gregory
- Africa's Rift Valley (1974), Colin Willock
- The Great Rift: Africa's Changing Valley (1989), Anthony Smith
- The Great Rift Valley of East Africa (2001), Anup Shah & Manoj Shah
- Tribes of the Great Rift Valley (2007) Elizabeth L Gilbert
- The Great Rift (DVD; 2010) BBC
- Birds of Kenya’s Rift Valley (2014) Adam Scott Kennedy