The black crowned crane, a charismatic bird species vulnerable to extinction from trapping and habitat loss, faces a new threat at one of its key habitats in the Sahel. Chad’s Lake Fitri, just south of the Sahara, is a massive wetland that is a magnet for African waterbirds and migratory birds from Europe. However, large numbers of fishermen who have fled the much bigger Lake Chad to the west to escape Boko Haram insurgents have pushed up the number of waterbirds – most notably cranes – caught accidentally as bycatch in Lake Fitri.
Lake Fitri is a vast wetland covering around 800 square kilometres in central Chad. The Ramsar Convention lists it as a wetland of international importance because it is a significant stopover site for migratory and resident waterbirds in Central Africa’s arid Sahel region.
In the last decade or so the presence of Boko Haram insurgents around the much larger Lake Chad, more than 300 kilometres to the west, has spurred the migration of thousands of fishermen from there to Lake Fitri. Numbers of fishermen at Lake Fitri now range between 1,000 and 6,000, depending on the season, compared to numbers that only peaked at around 700 in 2002. This near-tenfold increase has led to a surge in the number of waterbirds caught – mostly accidentally – as bycatch.
Among the birds most affected are black crowned cranes (Balearica pavonina), a species already considered vulnerable to extinction due to habitat loss and the trapping of wild birds for the pet trade.
“Livelihood harvest [of black-crowned cranes], even if it is by-catch, may not be sustainable,” says Pierre Defos du Rau, a wildlife scientist with the French Biodiversity Agency (OFB) and lead author of a new study into the impact of human migration on Fitri’s waterbirds.
“That is not an issue for Fitri only, but that’s probably an issue for the whole of the Sahel.”
With their striking black and white plumage and pincushion-like golden crown feathers, these iconic African waterbirds, which resemble southern Africa’s grey crowned cranes, inhabit wetlands and grasslands across West, Central and East Africa.
Experts say there could be as few as 33,000 mature black crowned cranes left across this range.
To estimate their number at Lake Fitri, Defos du Rau and his team, which included researchers from Chad’s General Directorate for Wildlife and Protected Areas, flew aerial surveys above the lake and its surrounding wetlands and forests every year from 2018– 2021.
Two researchers sat in the back of an aircraft piloted by conservationist Jaime Dias. Three rods attached to the wing struts on each side of the plane partitioned the view from each rear window into four parallel bands, covering areas up to 780 metres on each flight path. These bands helped the researchers estimate the number of birds along each transect and calculate the total populations across the lake.
The lake’s total number of black crowned cranes was estimated at around 2,000. Worryingly, the team estimated the number of cranes killed accidentally each year by the local community exceeded this figure. More data is needed to verify the findings, however, because the team was only able to do one harvest survey through interviews with fishermen around the lake.
The number of cranes caught by locals and the size of the crane population on Lake Fitri fluctuate.
“Maybe it was a good year [for local community members benefitting from the bycatch of birds, or] maybe it was a bad year, and maybe it was a good year or a bad year for the population size estimates,” says Defos du Rau.
It is also likely, the wildlife scientist says, that other well-protected areas in Chad, such as Zakouma National Park around 300 kilometres to the south, act as a source of cranes, thus maintaining numbers at Lake Fitri.
“Chad has been maintaining quite vast areas of source habitats for this species,” he says. “If there were no other well-conserved areas in Chad, probably the Lake Fitri population would be crashing down.”
During their surveys, the research team, which was part of the FAO’s RESSOURCE Project funded by the French Facility for the Environment and the EU, counted not just cranes but several other waterbirds, including spur-winged geese, sacred ibises, pink-backed and great white pelicans, garganey and white-faced ducks and large flocks of ruffs.
Of these, the geese, the ibises and the pelicans were also found to be at a high risk of overexploitation.
The key challenge at present is the massive, sudden immigration of people from conflict areas, especially in large parts of the Sahel, which is currently gripped by political instability, conflict, and violence.
Nevertheless, Lake Fitri’s seasonally flooded woodlands and huge marshes remain “a jewel”, says Defos du Rau. Their well-preserved state is a credit to the communities that live there, and the Chadian authorities who use only light-touch conservation laws to protect the area.
Defos du Rau says there can be sustainable use of natural resources. “But we don’t know how [this use] is going to evolve with this sudden immigration [of people] from outside of Lake Fitri.”
Lake Fitri’s resilience lies in its well-preserved ecosystems and the stewardship of local communities and authorities. However, sustainable conservation efforts are essential to protect black crowned cranes and other waterbirds from escalating threats, ensuring this wetland of international importance thrives for generations to come.
References
, , , , , , , , , , , , , , , , & (2024). Migration of humans fleeing conflict in the Lake Chad region may increase pressures on natural resources in Lake Fitri (Chad): A case study on waterbirds. Journal of Applied Ecology, 61, 2231–2243.
Further reading
Zakouma National Park is a park returned to vibrant wilderness, teeming with life. Zakouma offers a once-in-a-lifetime journey for travellers looking for safari adventure. Read more about Zakouma National Park here
Kingsley Holgate & the Afrika Odyssey visited Zakouma as part of an expedition connecting 22 African Parks protected areas. Read about their trip to Zakouma, Chad, here
Improved management in Zakouma, Chad, has led to healthier prey populations. Lions now favour larger species & prides are getting bigger. Read more here
To comment on this story: Login (or sign up) to our app here - it's a troll-free safe place 🙂.
