Thrill of waterbird census

It is 4.30am and birders taking part in the biannual national waterbird counts are converged for a briefing at Lake Bogoria National Reserve ahead of dispatch.

The partial darkness surrounding the camp only silhouettes the figures. The birds, the major hosts of the day, are barely awake, perhaps having the last round of sleep before dawn breaks.

Being a globally renowned birding destination that holds almost a third of the world’s flamingos, the first census within the Rift Valley lakes starts here. The teams are divided into eight groups, with each consisting of three members.

Each group has a birder’s starter pack - a datasheet containing a list of the common birds which are likely to be encountered within the vast territory. It also contains a list of less common and migrant birds which might be seen.

Besides the datasheets, critical tools such as binoculars and telescopes are mandatory for a successful bird count. Each team also has a soft copy of Birds of East Africa, a book that lists all birds, for ease of identification.

Birder John Gitiri says: “Early morning is prime time when the birds are active. It is their feeding time and the birders have to be within the sections they are supposed to cover, latest by 6am.”

 Bird data and trends

The exercise brings together experts from the National Museums of Kenya, Nature Kenya, Kenya Wildlife Service, and ornithologists from the Baringo County government. It also brought onboard volunteers.

“As an ornithologist from the county, the aim is to get data and trends of the birds within Baringo. This informs crucial decision-making,” said Michael Kimeli.

The exercise involves ravaging around the lake in search of the waterbirds. Kimeli’s team was deployed to the furthest and southern end of the lake, 26km from the main entrance.

The team has to ravage through the section until its end, recording each species spotted, whether individual birds or a flock.

“Being the last team, we will follow the shores until the very end. While other teams meet at some point, ours is to go along the shores until the tip,” Kimeli says.

Gitiri’s team is the second last; Team Seven. The team members start their counts where Kimeli’s team begins, only that they head in the opposite direction.

The plan is to walk several kilometres along the shorelines until they meet Team Six, to avoid overlaps. Gitiri’s team is covering the section within the famous hot springs and geysers, a favourite spot that often hosts flamingos in droves.

The count entails scanning flocks of waterbirds that comprise several species. Close flocks are best counted using binoculars, and more distant ones using a telescope.

Little flocks are counted individually while larger flocks are counted in blocks.

Experienced counters can accurately estimate 10, 20, 50, 100, or more birds almost instantaneously while looking through binoculars.

“In case of birds flying, we count those oncoming and those landing in front of us and not those flying from behind, heading to the direction we are headed. Those have probably been counted by another team,” Gitiri said.

Before counting a flock of birds, a preliminary scan is made with binoculars, and the overall number of birds and the proportion of each species are assessed.

To conduct counts on the other end of inaccessible shores, a team was deployed to vantage points specifically to scan through the distant shores.

Monitoring population

Richard Kipng’eno, a bird species expert from Nature Kenya, says bird counts are important in monitoring waterbird populations as well as describing changes in numbers and distribution.

“Bird counts also help us identify wetlands while providing information on the protection and management of waterbird populations through international conventions and national legislation,” Kipng’eno says.

 The national waterbird counts, he says, take place in January and July. Already, the counts have been conducted in Nairobi wetlands, and ongoing counts taking place in Nyanza, Western Coastal, and Rift Valley.

“The population trend of these birds also helps in taking appropriate action to avert that threat. Long-term monitoring and repeated data collection help a lot in coming up with policies,” Kipng’eno said.

The species expected to be encountered within the wetlands nationally include waterbirds regularly encountered at wetlands, including grebes, cormorants, pelicans, herons, egrets, storks, ibises, spoonbills, flamingos, ducks, geese, cranes, rails, jacanas, shorebirds, gulls, terns, and skimmers.

Martha Mutiso, a volunteer birder, says while there are challenges in ravaging through the shores in conducting the census, they are part of the fun in the exercise.

“Sometimes we get lost. We walk by the shores and reach a dead end and have to retrace our tracks. It is the fun part,” she says.

Over the years, data from waterbird counts in Rift lakes has shown declining trends, with Lake Nakuru having recorded massive declines in the number of flamingos.

Statistics from the ongoing census, according to Senior Warden James Kimaru, are expected to record lower flamingo populations as compared to numbers recorded in July last year.

“This is because the flamingos have flown back to Lake Natron to breed. By the time the next counts are conducted in July, the numbers will have increased because they will have flown back with their young ones,” Kimaru said.

Migration pattern

Current counts are also being undertaken in East African lakes to ascertain population trends and migration patterns. The counts also help in mapping breeding and feeding grounds.

“Rise in water levels also had an impact on the population of flamingos in the Rift Valley lake as it alters the conditions for the manufacture of algae. Over the past few months, the water levels have receded,” Kimaru says.

The population of flamingos in Lake Bogoria was estimated at 300,000 in January 2021. At the time, data indicated Lake Nakuru had 6,000 flamingos. Of these, 4,000 were living in sewerage treatment ponds near the lake.

Data shows the population of the birds in Lake Nakuru has plummeted from about 850,000 in 2000.