Nature Blog

Pink spots across the blue-green water; the low grunting sound of thousands of feeding flamingos in the distance –Lake Bogoria’s alkaline water creates a haven for almost a quarter of the world’s Lesser Flamingos after their breeding season in Tanzania’s Lake Natron.

This year, however, as one nears the shore the scene changes – dozens of flamingo carcasses dangle from the branches of dense Prosopis juliflora thickets that blanket the lake’s shores. Some flamingo seem to have lost the fight after struggling to disentangle from the sharp thorns of the low trees.

“It is worrying,” says James Kimaru, the Kenya Wildlife Service (KWS) senior warden at Lake Bogoria National Reserve. “Tens of flamingos are dying from being trapped by Prosopis bushes while attempting to either land or take off,”

Prosopis juliflora, a kind of mesquite, is an aggressive invader that replaces native vegetation, especially in dry areas where there is seasonal flooding.. It is ranked among top 100 invasive species globally, ravaging other arid and semi-arid areas of Ethiopia, Sudan, Egypt, West Africa, Australia, and other countries.

The plant was introduced in Kenya in the 1970s to rehabilitate the Arid and Semi-Arid Areas (ASALs), due to its resilience, fast growth rate and edible pods. Here it became known as ‘Mathenge’.

Prosopis does not normally grow on the shores of strongly alkaline or saline lakes, and flamingos can use the muddy shores dusted with white soda ash for takeoff and landing. In the past decade of heavy rain and catchment degradation, however, many alkaline lakes have flooded and become fresher. Prosopis became established in the shallow, relatively fresh water along the edges of the lakes.

“Flamingos prefers shallow water near the shores, which unfortunately has been taken over by Prosopis. This becomes a challenge whenever the birds are landing or taking off,” Richard Kipng’eno, Birding and Membership officer at Nature Kenya says.

Lake Bogoria has expanded by 7 square kilometre from its original size. The rising water levels have submerged administration offices and the gate of the \national reserve.

“Prosopis has also created navigational challenges in some parts of Lake Baringo,” Kipng’eno adds. “During the recent waterbird counts at Lake Baringo, we experienced some difficulties in manoeuvring boats through the Prosopis thickets.”

Large concentrations of Prosopis are to be found in Tana River, Turkana and Baringo counties. The invasive Prosopis has also colonised parts of Taita Taveta, Malindi, Samburu, Isiolo, Mandera, Marsabit, Wajir, Kajiado and Migori counties.

The plant has also been documented to have invaded some of Kenya’s important wetlands including River Tana Delta in Tana River County, Lorian Swamp (Isiolo/Garissa Counties) Lengurruahanga swamp (Kajiado) among others.

Prosopis charcoal is highly rated, but it is very difficult to cut the hard wood of the spreading, thorny trees.

Water levels continue to rise in the Rift Valley lakes. As a result, the alkalinity of some of the lakes is dropping. Changes in the lakes’ chemistry are causing a shift in the ecology of alkaline lakes, whose pH levels have decreased. The adjacent terrestrial habitats have also been affected, with large portions submerged in water. This impacts the carrying capacity for larger mammals in small, fenced protected areas like Lake Nakuru National Park.

Birds are key indicator species of changes in the environment. During the January waterbird census, large flocks of flamingos were observed at the oxygenation ponds in Nakuru, and a smaller flock at the Dandora sewage treatment plant in Ruai, Nairobi. This suggests that flamingos are seeking alternative habitats because of reduced food supply in the alkaline lakes.

At the Nakuru Sewage Treatment plant sitting adjacent to Lake Nakuru, more Lesser Flamingos were observed than on Lake Nakuru itself. Out of the total 6,000 Lesser Flamingos counted on both the ponds and the lake, 4,000 birds were recorded at the sewage treatment ponds. The Dandora treatment ponds recorded 40 Lesser Flamingos.

Waste stabilization ponds are well-suited for the tropics thanks to the high intensity of the sunlight and high temperatures which are important in the wastewater treatment processes. If other counties work towards achieving efficient wastewater treatment processes, especially for the urban centres, there could be alternative feeding habitat for Lesser Flamingos in times of crisis.

During January, Lesser Flamingos have also been reported on Lake Ol’Bolossat – a freshwater lake in Nyandarua County – in Amboseli National Park, on Athi Dam in Nairobi National Park, and on Lake Simbi Nyaima, Nyangweso Irrigation scheme and Ondago swamp in Homa Bay county.

The Waterbird census should be conducted consistently at traditional counting sites and observers should report opportunistic feeding areas for Lesser Flamingos in the country.

One of the results of deforestation is global warming. Trees and plants take in carbon dioxide and release oxygen back into the air. When we cut trees, a lot of the carbon dioxide released finds its way into the atmosphere. The carbon combines with other gases and absorbs sunlight. Normally, the radiation is supposed to escape into space but these gases, which last up to centuries, trap the heat in the atmosphere and causes the planet to get hotter. This is known as the greenhouse effect.

At St. Andrews Preparatory School, Turi, we are always encouraged to do something that would benefit the community, so I decided to plant some trees to help reduce the amount of deforestation and its impacts on our atmosphere. At school, we have a program called ‘Love in Action’. As part of this program, we eat simple lunches and wear our home clothes. We also contribute Ksh.100 from our tuck money to give to the people in need at the school’s charity, the Turi Children’s Project.

We also try and reduce, if not eliminate, food wastage. With less wastage, there would be less need for more land for agriculture. This would reduce deforestation. More land would also be available for the planting of trees.

People also cut down trees for fuelwood for cooking and to make homes warm. Trees also provide timber used for furniture and building. This means that we need to use trees sustainably, by planting as much as or more than we cut down. That’s why I decided to be part of the solution and plant trees, not of the problem by cutting them down.

Because of their many uses, we cannot stop cutting down trees completely. For that matter, for every tree we cut down, we should plant one or two in return. That way, we will continue to use trees sustainably for timber and fuelwood. That way, we will have a win-win situation.

Patricia Owiyo is a budding 11-year-old naturalist who is on a mission to conserve Kenya’s foresst. Patricia is a pupil at St Andrew’s Preparatory School Turi, Nakuru. The disruption of the school calendar by the Covid-19 pandemic made her come up with an initiative to grow trees in degraded forests. Patricia funds her tree-growing activities from savings made from sales of her handicrafts. Last month Patricia donated 400 tree seedlings to the Kijabe Environmental Volunteers (KENVO) for planting in Kereita forest, Kikuyu escarpment. Through friends, Patricia was also linked to Nature Kenya for support and guidance in her dream journey to grow at least 1,000 trees by 2021.