It is no secret that Kenya and the larger East Africa is fast losing biodiversity to effects of climate change and human activity.
The obvious noticeable changes are in shrinking indigenous forests and scrubland, drying rivers and swamps which translate to loss of habitat for both small and big animals. Birds have not been spared either.
Situated in the south of Kenya near the border with Tanzania are the Taita Hills, seen as a chain of massifs from the Nairobi-Mombasa highway stretching from Mtito Andei to past Voi in Kasighau. They are the northern extreme of the Eastern Arc Mountains that stretch into Tanzania.
These ancient massifs are one of the 25 biodiversity hotspots globally recognised for being the home of endemic flora and fauna. They are also home of the only known world population and now endangered Taita apalis (Apalis fuscigularis) bird species.
Working with funds from the Mohammed bin Zayed Species Conservation Fund, the Royal Society for the Protection of Birds and Nature and Biodiversity Conservation Union researchers have been working on saving the endangered native of Kenya’s Taita Hills.
According to recent surveys, ornithologists could easily find Taita apalis in Mbololo forest in the early 1990s. Not anymore. The tiny insectivorous songbird is now extinct in the forests of Mbololo, Chawia and Fururu.
Currently it can only be found in four small habitat patches, in a range of less than 500 hectares at Vuria, the highest peak of the Taita Hills in Mghange Dawida.
Fewer than 200 birds in total remain today in Taita Hills, which is also listed as an Important Bird Area, ranking its status higher.
In search of the songbird
Last December, I accompanied a team of researchers to Vuria, for another census. The road was a treacherous steep and muddy surface with deep galleys.
I was accompanying Dr Luca Borghesio, who in 2001 with Dr Mwangi Githiru and Daina Samba, started studying the bird. The first results showed a population of 600 Taita apalis.
Dr Borghesio and Dr Githiru are associated with the National Museums of Kenya. Their recent data however reveals a dramatic decline of the population of Taita apalis since 2001, and a projection of the population in Ngangao going extinct in the next two years.
Dr Borghesio said: “If you want to help a species to survive, research is very important.”
Standing on the hilltop of Iyale peak across the valley from Vuria, the mist clears to reveal a forest edged by farms and homesteads.
In the past two centuries, 98 per cent of the forests of Taita Hills have been converted to farm land, homesteads and forest plantations of exotic trees as human population increased.
“Almost all the natural forest has been converted into plantation forests,” explained Dr Borghesio, “because indigenous forests were believed to be worth nothing.”
Two years ago, the team embarked on a forest restoration project in Iyale and Ngangao, carefully selecting sites to restore.
“The plantation forest here is useless because the timber cannot be accessed. Therefore it’s ideal for converting into indigenous forest and increasing the habitat for Taita apalis. It requires collaboration between us the scientists and Kenya Forest Service,” says Dr Borghesio.
Today, only 410 hectares which is less than five square kilometres of indigenous forest exists in fragments on the hills.
Of the three massifs that form the Taita Hills – Dawida, Saghalla and Kasighau — it is only in a few forest fragments of Dawida at Ngangao, Vuria, Iyale and Msindunyi that current populations of Taita apalis are found.
In 2001, Ngangao alone had 60 per cent of Taita apalis population translating into 100 pairs, but following the drought of 2009, the forest lost more than 50 per cent of the bird population. Vuria had 60 pairs and Chawia and Iyale had less than 10 each.
“The situation in December 2017 is even worse,” said Dr Borghesio. “We expect a 20 to 30 per cent decline because of the drought of 2016-2017.”
Until recently droughts on the continent had a 10-year cycle. Now droughts occur every five years with negative effects on all forest-dependent species.
Even as scientists track and advise on how to save these bird, most of the population of Taita apalis are already lost, or will be lost soon.
“There are viable populations only in Vuria, Iyale and Msindunyi. All these habitat patches are on higher elevation, while at lower altitudes the birds are all but gone or hanging on a thread,” added Dr Borghesio. “But they could colonise new territories if more habitat is available at the highest altitudes.”
In 2016, Dr Wagura and Dr Borghesio began working with the local community on a landscape restoration project to clear the forest plantation of exotic invasive trees like Acacia mearnsii and Pinus patula planted for commercial purpose.
In the space of a year the land cleared has a natural regrowth of indigenous plants like lobelia, tree ferns and more.
The Taita apalis basically a forest bird but lives and breeds in open gaps in the forest in low bushes. “The bush is the critical habitat for this species,” explained Dr Borghesio.
Protecting the habitat is only part of the story. The other threats to the bird are drought and predators.
“With every drought there is a drop in breeding,” he said. “This is because when it rains there are a lot of insects for the bird to eat. So the breeding success for insectivorous birds like Taita apalis depends on the rains to bring the insects.”
Our late December trip coincided with the birds’ breeding season, which happens once a year between November and February corresponding with the short rains.
Maina Gichia, the field assistant has been monitoring the nesting sites over the years and marking them with GPS. Since 2016, his team has installed camera traps funded by Birdlife International/Royal Society for the Protection of Birds (RSPB) by the nests.
“What we are seeing is that even though Ngangao is the best protected forest, it has the highest density of forest animals predating on the nests,” said Maina.
Images show dormice attacking the nests at night and the African goshawk raiding during the day. The researchers still do not understand the causes of high abundance of predators in the forest which is located at lower altitudes.
“In Ngangao, more than 90 per cent of the bird nests are predated before the juvenile birds can leave the nest. At higher altitudes, in Vuria and Msindunyi, predation rates are lower at 60 per cent,” said Dr Borghesio.
“So we’re seeing that the breeding success is dependent on several parametres. The camera traps are helping us to know what other threats the bird faces.”
Nature Kenya — the country’s oldest nature conservation organisation, established in 1909 — and its site support group Dawida Biodiversity Conservation group (DABICO) is the forefront of saving the bird.
The organisation is raising money to buy or lease parcels of land at high points of Taita Hills for reforestation and also engage local people on how to protect this endangered bird species. The organisation is targeting to raise $100,000.
But first, the Dawida Forest Biodiversity Resource Centre at the edge of Ngangao needs to be upgraded beyond the budget camp site for researchers, into a proper research outpost if we are to save the little song bird from extinction.