Ghanaian farmers near Lake Bosomtwe face rising crop pests and a receding lake. A collaborative effort blends local wisdom, science, and traditional farming to secure this vital ecosystem’s future.
In the thick of the Guinean Forest, Cecilia, Margaret, Comfort, and Josephine walk through their small patches of farmland.
At the heart of Ghana’s central Ashanti region, the forest surrounds the mythical Lake Bosomtwe, one of the six lakes in the world formed by a falling meteorite. More than a million years old, it is the country’s only natural lake and one of the few in West Africa.
The women are farmers belonging to the 20 or so villages around Bosomtwe. They grow okra, cassava, sugarcane, palm oil, plantain, and cacao at a subsistence level.
The forest and lake’s idyllic nature can trick an unsuspecting observer into believing all is well in paradise.
The women working in the forest daily understand reality better.
Speaking in the local dialect, Twi, the women explained with the help of a translator that moths are destroying their crops, that pests reduce the marketability of okra by making it appear damaged, that crickets and hoppers cut into the crops, and that small flies penetrate the women’s eyes and noses when they work.
It wasn’t always like this. The women noticed the increase in the pest population around five years ago. They attributed the phenomenon to the changing rainfall patterns, noting the pests thrive in periods of increasingly low rainfall. They also pointed to the loss of trees and the use of chemical pesticides as reasons.
To understand pest behaviour, the women lay Malaise traps on their plantations to capture different insects. The samples are then sent for study to the International Barcode of Life (IBOL) Consortium, based at the Centre for Biodiversity Genomics in Guelph, Canada.
IBOL’s research is part of an intervention led by Canadian development organizations, the World University Service of Canada and the Centre d’étude et de coopération Internationale.
Supported by Global Affairs Canada, the three-year project began in 2023, and it offers nature-based solutions to the challenges faced by communities dependent on the broader Guinean Forest, encompassing Ivory Coast and Guinea alongside Ghana.
From field to lab
With the help of Malaise traps, “we aim to identify the insect species present within the landscape,” said Benjamin Afful, a project officer at the faith-based conservation organization and project implementation partner, A Rocha Ghana.
Afful, a trained soil scientist, explained that “once we identify the species and their populations, we can make informed decisions regarding appropriate land management and propose effective interventions.”
Afful gave the example of the fall armyworm, typically found in North and South America, which was discovered in Ghana a decade ago. He said climate change has created a conducive environment for the worm to thrive, including the forest around Bosomtwe.
“These worms infest maize plants, feeding on them from a young stage and ultimately destroying them,” Afful added.
A Rocha Ghana is exploring locally available materials for pest control, such as extracts from the abundant neem trees around the lake.
“Spraying neem extract on crops can deter insects,” Afful said.
Not all insects are pests. Many play a positive role in maintaining the ecosystem’s health. Knowing all the species around the lake’s forest allows the researchers “to determine their ecological roles: are they beneficial, such as pollinators or nutrient recyclers?” Afful explained.
A decline in pollinator populations could explain reduced crop production,” Afful added, which could “inform appropriate interventions, such as promoting organic farming practices.
“Determining whether to adopt organic methods and identifying suitable organic amendments becomes crucial for insect conservation.”
Afful added that their “pest control strategy aims to maintain pest populations below the economic threshold, rather than complete eradication.
“Some insects are beneficial, becoming problematic only when their numbers exceed a certain level.”
According to Afful, the analysis of samples collected by the women will help “assess if agroforestry systems support greater insect species diversity compared to monoculture systems.”
He added that the “comparison will inform decisions regarding land use, promoting agroforestry to enhance insect diversity and abundance, which are critical for food security.”
Roots of recovery
Cecilia, Margaret, Comfort, and Josephine continued the tour of the forest. While the farmers await lab results from IBOL, other interventions, such as agroforestry, are being implemented.
The women explained that adding tree cover helps the crops, as the shade allows the soil to maintain moisture. More trees also mean fewer chances of insects feeding on crops.
By the shore, Dorcas Boama explained how she has seen the lake recede over the years. Speaking with the help of a translator, Boama said that the sun falls directly on the lake. If they have trees to create shade, it reduces evaporation and helps maintain the water level.
The lack of canopy around the shores also increases siltation, pushing the water back. The receding lake increases land availability, and the land around the lake is prized for farming, reinforcing the cycle of deforestation and lake degradation.
Grass and trees block the sand and other sediments coming from uphill during the rains, Boama added. Indigenous tree species, such as mahogany, have been planted as part of the intervention to prevent the lake from drying and receding. Fruit trees like coconuts and avocados have also been planted, allowing the farmers to sell the produce and earn extra income.
Festus Owusu, a resident of one of the villages around the lake, said the areas of the lake’s shore with trees have remained stable. He hopes to receive more seedlings during the project so that they can plant enough trees to prevent the lake from receding. Parts of the lake’s shore that don’t have trees recede yearly.
Roots of responsibility
Managing a 49-kilometre-square lake and the surrounding forest requires governance.
Ghana’s Forestry Commission has created Community Resource Management Areas (CREMA), which have the responsibility and authority to implement laws to ensure the conservation of areas under its jurisdiction.
Lake Bosomtwe is also looked after by a CREMA.
Sitting under tree shade by the lake, Nana Boamah, CREMA’s project coordinator, explained with the help of a translator that they have demarcated the lake into three zones – core, transition and buffer – where activities such as farming, tree cutting, fishing and using water for domestic activities such as cleaning are banned.
Nana Boamah said that CREMA, comprised of members and elders from each Bosomtwe village, also carries out educational and awareness workshops to prevent the use of chemicals and pesticides in farms that drain the lake, degrade the water quality, and affect the fish habitat.
But education alone is insufficient, said Nana Boamah, and villagers need alternative income streams to transition to more sustainable activities.
CREMA explored snail farming, but it proved to be unsuccessful, as the villagers were unable to keep the snails alive.
Grasscutters are a delicacy in the region, and Nana Boamah believes rearing the insect could be a viable option. Beekeeping could be another.
However, due to financial constraints, these initiatives, along with the technologically advanced farming methods that CREMA has attempted, have yet to take off.
An intervention that seems to have been adopted by farmers is the traditional methods of farm maintenance called proka and bucha.
Charles Tuffour, an organizer with CREMA, explained that farmers typically prefer to clear the land by burning it with chemicals, which harms the environment. However, according to Tuffour, CREMA has made farmers understand that farming techniques matter more than farm size.
Traditional farming techniques, such as bucha, or mulching, involve amending the soil around crops with organic matter such as crop residue, grass and leaves, fruits, and livestock manure. Mulching helps improve soil fertility and nutrients, moisture and temperature.
Proka is a no-till farming method in which the mulch stays on the farm instead of being burned with chemicals.
Tuffour said that when compared, traditional techniques produce better yields than farms that use chemicals.
Leading the way
Back in Bosomtwe, the women ended the tour at their village. They have planted the trees and adopted mulching, and they hope that samples from the Malaise traps will help them manage the insects and pests on their farms.
Women are the backbone of the communities around the lake. While most of the land belongs to men, the women sell the produce and the fish in the market, ensuring a vital income stream for their families.
A meteorite formed Bosomtwe, but its women aren’t waiting for an out-of-this-world intervention to face the increasing climate and environmental challenges.
Credit: Jahanzeb Hussain
