feature image

Atidza Densu Delta Mangroves in Ghana

Fisheries and Mangroves in Ghana: Atidza and the Densu Delta Ecosystems

Tidal river fishermen have degraded the mangrove forest cover around the Densu Delta, a Ramsar-designated wetland, for traditional fish traps. Only around 16 red mangrove trees (Rhizophora species) are left standing, having all been cut down for the traps, fuelwood, and timber. But mangrove biomass is critical for fish assemblages, which the fishers depend on. This habitat degradation has led to a loss of biodiversity in the area — leading to a decline in fish stock in the Densu intertidal zone. The video below explores this problem.

October 7, 2020

Urban poor fisherman harvests his Atidza trap. Copyright © 2020 Muntaka Chasant

Tidal river fishermen have degraded the mangrove forest cover around the Densu Delta, a Ramsar-designated wetland, for traditional fish traps. Only around 16 red mangrove trees (Rhizophora species) are left standing, having all been cut down for the traps, fuelwood, and timber. But mangrove biomass is critical for fish assemblages, which the fishers depend on. This habitat degradation has led to a loss of biodiversity in the area — leading to a decline in fish stock in the Densu intertidal zone. The video below explores this problem.

Intertidal habitats are harsh environments for wildlife.

A much tougher environment for plants.

However, mangrove forests have appeared in nearshore landscapes where indigenous people did not plant them — to keep watch.

We did not understand them very well in the past. Now we do.

Adapted to harsh environments on the edge of tropical and subtropical seas, mangroves are an important link between land and ocean.

Mangrove forests stabilize shorelines, reduce erosion, and provide essential habitats for a wide range of animals, including threatened and endangered species.

However, these critical habitats are disappearing at an alarming rate in the tropics, including in Ghana.

We have lost 50% of the world’s mangroves in the past 50 years, says the Global Mangrove Alliance1.

More than 40% of the total global area of mangroves is in just 4 countries: Indonesia (19%), Brazil (9%), Nigeria (7%), and Mexico (6%).2

Having degraded the mangrove habitats around the Densu Delta, tidal fishermen are now catching fewer fish, a tell-tale sign of unsustainable exploitation.

The video below explores the impacts of unregulated fisheries and the overexploitation of a coastal ecosystem — a deltaic wetland in Accra, Ghana’s capital city.

It’s a short story about the changing environment and how it is shaping the livelihood of the people who rely on the Densu Delta as a source of jobs and food.

There are only around 16 red mangrove trees (Rhizophora species) left around the Densu Delta, a Ramsar Designated wetland. There were thousands of them in the past. The video below explains why:

Mangroves in Ghana Statistics

Total mangrove area in Ghana covers around 137 km², according to a 2007 UNEP report3.

Mangroves in Ghana are mostly found in nearshore lagoons and estuarine environments — mainly along the western coastline between Ivory Coast and Cape Three Points. This includes the Greater Amanzule Wetlands and Akwidaa (around 7 km onwards from the Cape Three Points area).

The Volta Delta area also has a large mangrove population.

The UNEP study identified six (6) main species of mangroves in Ghana:

  • Rhizophora racemosa
  • Avicennia germinans
  • Laguncularia racemosa
  • Rhizophora harrisonii
  • Conocarpus erectus
  • Acrostichum aureum

A Ramsar designated site, the Densu Delta area in Accra was once home to thousands of red mangroves. There are now only around 16 Rhizophora racemosa trees left standing — having all been cut down for fish traps, lumber, and fuelwood.

The remaining scattered stands of Avicennia germinans around the Densu Delta are also under threat.

The degradation around the Densu Delta — the main focus of this page — stands in stark contrast to the trends in other mangrove-colonized areas of Ghana.

No Fish to Catch, Fisherman is Going into Commercial Driving After 25 years of Fishing

We have cut them [mangrove trees] all down — for fish traps and fuelwood.

“There were many many red mangrove trees around here,” said David Kpaligah, a fisherman around the Densu Delta. “They are all gone now. We have cut them all down — for fish traps and fuelwood.”

David has an everyday experience with mangrove trees. He has been fishing around the Densu River since 1995.

But there are now no more fish for him to catch.

Compared with marine fisheries, Ghana’s collapsing inland fisheries have received little to no attention at all.

“The environment has changed. I now want to stop fishing and become a commercial driver because there’s nothing left for me to catch,” David added, with a hint of regret in his voice.

At almost 50 years of age and after 25 years of fishing, David wants to start taking driving lessons — to take care of his family of 10 children and a wife.

David is indeed aware (as you can see in the video) of the key role, for instance, red mangroves play in mangrove fish assemblages.

Cutting down mangrove trees seems to have been a mainstay of the area’s economy dating back to the early 80s.

According to David, red mangroves colonized the Densu Delta area before Ghana’s 1983 famine4 5.

People trooped in from nearby areas, including Tsokomey, Bortianor, and Faanaa, to cut down the red mangrove trees for fuelwood during the famine.

Cutting down the black mangrove trees (Avicennia germinans) intensified from 2012 after a different group of people took over ‘ownership’ of some parts of the area, David told me.

The 80s famine period was probably the golden age of cutting down mangrove trees around the Densu Delta.

What Are The Ecological Benefits of Mangrove Trees?

Mangroves are transitional ecosystems, especially near the Densu Delta, where freshwater, land, and the ocean meet.

Mangroves ensure the sustainability of coastal ecosystems. For instance, many fish species around the Densu Delta rely on mangrove biomass for productivity.

Support for wildlife — including monkeys, crocodiles, migrating songbirds, and many shorebirds species.

Mangroves serve as breeding and nursery habitats for many fish species, including blackchin tilapia, grey snapper, mosquito fish, and leatherjacket fish6 7. Many fish species and crustaceans rely on mangrove ecosystems.

Wetland ecosystems teem with life.

Male fiddler crabs claw-dance to mark their territory and attract females. You can see this in the video. Though they don’t engage in violence at all times, they also use the claws as weapons during duels.

The Densu Delta intertidal area hosts a large population of reed cormorants. Also known as long-tailed cormorants, they spend their time diving and swimming underwater with their webbed feet to snatch fish for a meal.

Degradation and habitat loss from the cutting down of mangrove trees put pressure on bird species around the delta.

As a source of jobs and food. Populations living near the coast depend on mangroves for their livelihoods. Some harvest them for house construction. Others use and sell them for fuel, and their antibacterial8 properties.

As you can see on this page, it also helps the fishermen to construct brush parks. The urban poor also rely on fish from these artificial habitats as a source of jobs and food.

The urban poor who rely on trading the fish caught in the lagoon and tidal areas are now on the brink of extreme poverty due to declining fish catch.

I felt deeply for Victoria Governor in the video.

They were very appreciative of the little money I donated to them the last time I was there. They can use some help right now, especially as the pandemic is projected to plunge more than 70 million9 people into extreme poverty.

Provide coastal protection. You may not even know it, but mangroves could be protecting your property from flooding if you live near the coast.

Mangroves play important roles in defending coastlines against erosions10 by trapping sediments. They reduce risks from strong winds, wave attacks, and also act as a buffer against storm surges11.

Carbon sequestration. As natural carbon sinks, mangroves sequester carbon dioxide from the atmosphere and store it in their biomass over long periods12They do this even more effectively than tropical rainforests13. This helps to mitigate the impacts of climate change.

Despite the many ecological benefits, these trees are being degraded at an alarming rate around the Densu Delta. The red mangroves are gone. So those are out of the question.

The remaining scattered black mangrove stands are also on their way out.

These photographs below were within 5 minutes part.

Saw this one:

Turned around a few minutes later and saw this:

Another time:

Densu Delta fishers are indeed aware of the key roles of mangroves in fish assemblages. You can see David explain this in the video above.

Why do they still cut them down?

Why Do Coastal Populations Still Cut Down the Incredibly Important Mangrove Trees?

Densu Delta’s intertidal habitats support livelihoods and provide essential food, including blackchin tilapia, blue crabs, and oysters. They also serve as spawning grounds and nurseries for a wide variety of species. Mangroves play an important role in this.

Despite its support for fish assemblages, mangroves in the area have been decimated in recent years for Atidza brush parks.

Atidza Brush Park Method of Fishing in Ghana

You probably saw the environmental footprints of the Atidza method of fishing [in Ghana] in the video.

Atidza around the Densu River involves sinking mangrove brush bundles to the bottom of the water to create artificial habitats. Blackchin tilapia takes refuge in the shelters, form schools, and spawn there. They also serve as nursery habitats for juvenile fish. The fish populations thinking they are safe, the fishermen wait several weeks before harvesting them.

They use a net to surround the shelter and gradually remove the submerged branches and debris until the net is drawn together to entrap the fish.

A new habitat is rebuilt simultaneously with the old mangrove bundles.

This method of fishing is practiced in many parts of West Africa — including in Benin and Nigeria.

I have filmed the Atidza process in the video above. Do see it if you haven’t.

Is Atidza a Sustainable Practice?

Atidza supports countless livelihoods, yes, but it is clearly not a sustainable practice around the Densu Delta.

Overfishing has led to a decline in fish catches around the area. As a result, a lot of the fishermen are having to expand by creating more Atidza traps.

The longer the wait, the more fish are caught, but they cannot wait for several weeks to harvest just one trap. Having a few of these traps means they can harvest one or two every week.

David alone has nine of these traps.

This frustration has led to the fishers regularly cutting down the mangrove trees to use them for the Atidza traps.

Aside from the impacts of Atidza on mangrove vegetation, this method of fishing also put pressure on fish populations in the area, including pre-spawning fish.

Disappearing Salt Marshes

Salt marshes reduce flooding, filter runoffs, and protect coastlines from erosion.

Sea level rise and the Weija Reservoir spillage have resulted in significant saltmarsh biomass loss around the Densu Delta.

Vast swaths of the deltaic marshes in the area have drowned and transforming into tidal flats.

Tides are coming farther inland. As you saw in the video, ocean tides now cover the lower marsh areas — squeezing the rest against drier land.

Home for several species, they are disappearing along with the life systems they support.

There probably wouldn’t be much left of the marshes by the end of the decade.

For Landscape and Nature Photography lovers

A few photographs for landscape and nature photography lovers:

What is the way forward?

The trends documented in this post are having a serious impact on fish assemblages, distribution, and abundance of mangroves around the Densu Delta.

Restoring these coastal wetlands and mangroves would require sustained efforts and commitments.

It would also require engaging the populations who rely on these ecosystems as a source of jobs — by integrating them into management and conservation efforts.

In the video, David has admitted that they are the architects of their own doom.

Ghanaian authorities may or may not be aware of this problem. If they are and have ignored it, then that’s a problem. If they are not aware — well, that’s even a much bigger problem.

Copyright © 2021 Muntaka Chasant



Comments (1):

  1. Henry Adjei Anderson

    October 7, 2020at 5:52 pm

    I’ve enjoyed reading this article and I think we have to protect our environment. The government or chiefs of the area should educate the fishermen on the effect these Atidza is causing climate change in the world.


Leave a comment below to join the conversation

%d bloggers like this: