Rising water level driving flamingos away from scenic Lake Nakuru

By KIBIWOTT KOROSS

In 2009, it was feared that Lake Nakuru was drying up.

Most of the lake had been reduced to a pan with tourists and motorists walking around as the magnificence and splendour of the flamingo marked pink-rimmed shoreline disappeared.

The birds are fleeing to other areas in search of food because the salinity of the water has reduced the growth of the blue-green algae, the flamingos’ main food. The lake dried up once between 1951 and 1953.

Low water levels then caused by a persistent drought between November and March 2009 and 2010 saw the flamingos migrate, leaving just about 1,000 birds.

However, the trend has been reversed four years later, with the flamingos migrating once more, not due to lack of water but excess of it.

The increase in water level reduces the salinity of water in the lake thereby reducing algae.

Water level has risen by as high as six metres, submerging sections of acacia forest and reducing the salinity of the water, thereby rendering the aquatic habitat unsuitable for flamingos for the time being.

“Flamingos are moving to Lake Bogoria for food,” said Kenya Wildlife Service’s Jonathan Kirui, who is in charge of Central Rift region.

The lake has burst its banks, swallowing parts of some buildings, including the cash office and residential houses meant for rangers.

In a recent visit, The Standard on Saturday witnessed a pit latrine submerged by the rising water.

A countless number of acacia trees now under water are drying up. The bank, until a few months ago, was more than 300m away.

KWS says water levels rose by about six metres, and the size of the lake has increased from 42sqkms to 68sqkms.

This is not good news to the park, as the flamingos have temporarily moved to Lake Bogoria, leaving behind a few hundreds owing to a reduction in their food supply.

Scientists now warn that should there be more rains, the lake would continue swelling. This could spell more doom to Lake Nakuru, home to more than one million flamingos and a number of rhinos.

According to KWS, Lake Nakuru National Park has over 450 bird species, with the biggest percentage being flamingos and pelicans.

        Heavy siltation

The scientists have attributed the changes in the size and depth of the lake to increasing human population, rapid land use changes in the lake’s catchment area and climate variability.

Alice Bett, a KWS scientist, says continued rains and constant flow of rivers Nderit and Makalia could be the reason why the lake burst its banks.

“We have had long and prolonged rains in the past few months and the main rivers Makalia and Nderit which feed the lake have been flowing constantly. There have also been cases of over siltation.”

She said a team of hydrologists are currently studying the situation. “This is an abnormal situation…the water levels have risen by almost six metres in the recent past,” she said.

With the meteorological department projecting heavy rains for the next three weeks in its latest weather forecast update, the water levels at the lake are expected to rise.

Other than the favourable rains and global warming, some heavy siltation has been cited as another major factor choking the lake.

“This is not good. As we speak, it is raining in Nakuru and that means more water into the lake,” said Kirui.

Dr Ephrahim Mukasira says the growth of Nakuru town could also have contributed to the lake bursting its banks.

Speaking to The Standard on Saturday on phone, Dr Mukasira, the director general of the Kenya Agricultural Research Institute, said most of the town has been paved thereby reducing ground water uptake.

 “Most of the water that used to infiltrate into the ground has been channelled into the lake. This is very possible because surface run off is high,” he says.

     Mau forest logging

Dr Mukasira says siltation has also contributed to the lakes expansion owing to poor farming methods upstream and the rehabilitation of Mau forest, which is the main source of the rivers feeding the lake.

It is estimated that there are about one million farmers in the Lake Nakuru water catchment, which includes the Mau Forest that has been logged for commercial tree species during the last two decades, exposing the soil to severe erosion.

There are also reports that poor handling and refuse disposal is contributing to the chocking of the lake.

Two months ago, KWS said pollution by industrial and domestic wastes and agrochemical pollutants from farm lands were among the threats to the lake.

According to a KWS official, storm drains get blocked and the water flows directly into the lake during the rainy season, carrying with it toxic substances.

These toxic wastes include fertilisers, agrochemicals from farms, heavy metal from industries in the densely populated Nakuru town and Njoro sub-basin.

             Weather patterns

But Wilfred Osumo, the National Environmental Management Authority county director refutes this saying the county is handling its refuse collection well.

He agrees with Makasira that the lake is expanding as a result of Mau rehabilitation.

“Seasonal rivers including Njoro, Makalia, Nderit, Naishi and Larmdiac have been flowing continuously for the last one year due to improved hydrology as a result of conservation efforts in the Mau Complex,” he said on phone from his Nakuru office.

River Larmdiac is an underground water source inside the park, which had dried up many years ago, but it has become alive and has even caused fault lines in the park.

Makasira says change in weather patterns as a result of global warming is a major factor.

“We are in an era where almost every climatic condition has changed. It is possible that what we are seeing is as a result of climate change,” he said.

KWS scientist Joseph Edebe says the trend of flamingos have changed due to the changing weather patterns.

Lake Nakuru receives 75 per cent of its surface flow from streams originating in the Eastern Mau Forest.

The park receives 300,000 to 500,000 tourists annually.