- Nigeria’s Cross River state, famed for its gorillas, chimpanzees, drill monkeys and forest elephants, is also part of an ecological region known to harbor the greatest diversity of dragonflies and damselflies in Africa.
- A Nigerian-Dutch team recently published details of three new species of dragonfly it found during its survey of four locations across the state, alongside dozens of other dragonflies and damselflies, including some that are now critically endangered.
- Many of the forests and streams the insects live in are threatened by fire, deforestation and the expansion of commercial oil palm plantations.
The Gambles’s flatwing, a critically endangered damselfly with glittering translucent wings, is so rare scientists estimate there could be as few as 250 left in the wild.
When zoologist Abiodun Adedapo first saw one perched on the back of a dry leaf in Nigeria’s Obudu Mountains, it was a pivotal moment. “We had read about it and seen it in the books, but coming across the species in the field was quite amazing,” he says.
Known to science as Neurolestes nigeriensis, the Gambles’s flatwing is among six vulnerable, endangered or critically endangered damselflies found in Obudu, whose high-elevation grasslands and valleys, interspersed with patches of evergreen forests and crisscrossed by freshwater streams, nudge up to the highlands of western Cameroon.
Large expanses of those forests have been felled.
“Because of the very high levels of deforestation going on,” Adedapo says, “the patches of forest on the Obudu plateau have been drastically reduced to only the edges of the streams.”
When he saw the Gambles’s flatwing in early 2022, he and colleagues from Nigeria and the Netherlands were surveying Obudu and other parts of Cross River state for rare and threatened dragonflies and damselflies, known collectively as odonata. Cross River’s forests are part of an ecoregion known to host Africa’s highest diversity of the insects.
The team recently published a comprehensive account of the expedition, including details of the habitat degradation they witnessed in some of the surveyed sites.
Most of Obudu’s forest patches lack formal protection, and compared with other locations surveyed during the expedition, they were found to be the most heavily degraded, the team said.
In addition to the shrinking forest patches, the expedition members observed fires in Obudu’s remnant forests on each of the days they were there. Frequent burning, clearance to make way for agricultural fields and overgrazing by cattle trigger runoff of nutrients and sediments into streams, they reported.
And it’s in these streams that the dragonflies and damselflies begin their life cycles.
Obudu’s streams are naturally fast-flowing, and filled with highly oxygenated water, vital for sustaining species such as critically endangered Gambles’s relics (Pentaphlebia gamblesi) and vulnerable red relics (Pentaphlebia stahli). These damselflies, two out of just three members of a genus unique to Africa, are relicts, possessing bodily features — especially in the larval stage — that are very different from other damselflies.
“They are considered an ancient or very early form of the modern-day damselflies,” Adedapo says, likening them to a population of Homo habilis primates still living alongside modern humans.
The Gambles’s relic is so rare, in fact, it hasn’t been documented since the first specimen was collected in Obudu in 1973. It was a target species for the 2022 expedition, and though the team didn’t spot any, they did find damselfly larvae — the stage between eggs and adult damselflies — in the Afundu stream that could have belonged to the species.
It gives some hope the insects are still alive, but also underscores the importance of protecting the only place on the planet they could still be found.
Emmanuel Akindele, a freshwater ecologist at Nigeria’s Obafemi Awolowo University, wasn’t part of the 2022 expedition, but says he considers Obudu’s freshwater streams and surrounding forests to be a biodiversity bank in need of better protection.
In 2021 and 2022, he and his team conducted their own survey of three sites in Cross River state, including the Obudu Mountains. Their focus wasn’t just dragonflies and damselflies, but also mayflies, stoneflies and caddisflies. These tiny aquatic insects — known to scientists as EPT taxa — live in freshwater streams and rivers and their sensitivity to changes in water quality mean they’re helpful indicators of its purity: the more of them there are, the purer the water. Obudu is especially well-supplied.
A count of just 10 different species would indicate “sound biological integrity,” Akindele tells Mongabay. In the Afundu stream, protected on one side by a mountain range but exposed on the other to deforestation, burning, overgrazing and runoff, he and his team found 30.
“There are no previous reports of such high numbers of [aquatic insects] anywhere in Nigeria,” Akindele says. “The EPT taxa could be higher in both richness and abundance if Afundu and its riparian corridor were protected.”
Joseph Onoja is director of the Nigerian Conservation Foundation (NCF), an NGO that runs Becheve Nature Reserve in Obudu. He says protecting more areas with the support of donors and local communities would meet many pressing needs, including human health and ecological integrity.
But land in Obudu is a precious resource, he says. With no access to piped water or sources of energy, many communities there would be hard-pressed to cede more forests for conservation.
“These areas are like the supermarkets and grocery stores of the local community,” he says. “They are enlightened enough to be able to understand the importance of [protecting] the forest – it’s just that they are pushed to do otherwise.”
“We have to provide alternatives to be able to dissuade these communities from getting into the forest.”
NCF has assessed carbon stocks in forest reserves it manages in Obudu and elsewhere with a view to generating income “through real, authentic carbon trading,” Onoja says.
“If such benefits come directly to the community, they may be convinced to want to have more of their forest reserve under protection.”
Raising community awareness about biodiversity richness is also vital.
More than two years on from the expedition and his first encounter with the rare and critically endangered Gambles’s flatwing, zoologist Adedapo is now researching the freshwater invertebrates of the Obudu plateau.
With support from the U.K.-based Rufford Foundation and the UAE’s Mohammed bin Zayed Species Conservation Fund, he has also founded a Dragonfly and Damselfly Conservation Club for youths and some older members in the Becheve community.
Armed with collecting nets, they go on regular field trips in search of odonata, and Adedapo tells them about the insects they find. On a recent trip they found one of the three new species of dragonfly discovered during the 2022 expedition. It doesn’t yet have a scientific name, but that didn’t dampen the enthusiasm of club members at seeing it.
“I thought it was just me, but when they came to know about the concept of a new species they were quite fascinated,” Adedapo says. “Some of them were even advocating that it be named after their community.”
Adedapo has discovered new areas in Obudu that contain threatened species. This has prompted collaborations with other scientists from different disciplines keen to highlight sites worth protecting.
One such place is Monkey Face View Valley, near the northeastern edge of Becheve Nature Reserve. It supports at least three species of threatened damselflies, including red relics, banded jewels (Africocypha centripunctata) and blue-shouldered yellowwings (Allocnemis vicki). It’s also home to endangered Preuss’s monkeys (Allochrocebus preussi) and at least two vulnerable bird species: Bannerman’s weaver (Ploceus bannermani) and white-throated babbler (Kupeornis gilberti).
Encouraging habitat protection for larger, more charismatic animals, whether in Obudu or elsewhere in Cross River state, will also benefit those at the bottom of the food chain, like dragonflies and damselflies.
“A particular pristine patch of forest that is good enough for gorillas and the bigger species,” Adedapo says, “would definitely support the least-known species, like insects.”
Surveying the wider area
Obudu isn’t the only place in Nigeria’s Cross River state where freshwater systems are threatened.
A joint Nigerian-Dutch expedition surveyed 19 sites at four separate locations from January-February 2022.
They found the least-impacted areas were in lowland evergreen forests around Aking and Ekang. Much of those forests fall within the Oban section of Cross River National Park, the team noted in its report published recently by the International Dragonfly Fund.
At the time of their survey, however, large-scale oil palm plantations were being developed south of Aking.
“From experience, going through many of the other forests in Cross River state, I have seen so many palm oil plantations spreading,” says Abiodun Adedapo, an expedition member.
“If you travel from [the state capital] Calabar, for example, to Obudu, on your left, on your right, you’ll see lots of expanses of palm oil plantations, so I can only imagine what will be happening in the interior areas that are not close to the main road.”
Adedapo and other members of the expedition also witnessed extensive forest loss on the steep slopes of the Afi Mountains, within Afi River Forest Reserve, which is home to endangered drill monkeys (Mandrillus leucophaeus), Cross River gorillas (Gorilla gorilla diehli) and possibly even forest elephants (Loxodonta cyclotis) in the south.
Shifting agriculture in the Magbe River catchment area above the village of Buanchor, located at the foot of the Afi Mountains, triggered wildfires that swept all the way up to their summit, the team noted in its report. Deforestation has left hillsides vulnerable to erosion and landslides, which have devastating impacts on freshwater streams.
“These things are not under control, they’re not being checked,” Adedapo says. “It’s only a matter of time before many of the [odonata] species will be wiped out.”
Banner image: Gambles’s flatwing (Neurolestes nigeriensis). Image © Jan van Leeuwen.
New assessment finds dragonflies and damselflies in trouble worldwide
Citations:
de Vries, J. P. R, Buesink, R., van Leeuwen, J., Ekpah, O., Adedapo, A. M., Owolabi, B. A., … Dijkstra, K.-D. B. (2024). Dragonflies and damselflies in Cross River state, Nigeria (Odonata). International Dragonfly Report, 184, 1-32. Retrieved from Dragonflies and Damselflies in Cross River State, Nigeria (Odonata)
Akindele, E. O., Adedapo, A. M., Akinpelu, O. T., Fagbohun, I. R., Kowobari, E. D., Oladeji, T. A., … Aliu, O. O. (2024). Freshwater macroinvertebrates along the Nigeria-Cameroon border enhance the conservation value of the lower Guinea forest biodiversity hotspot. Journal of Environmental Management, 355, 120532. doi:10.1016/j.jenvman.2024.120532
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