Another Invasion Threatened: the Amazon Frogbit

Free-floating and rooted Amazon Frogbit on the Zambezi river, October 2013.

Free-floating and rooted Amazon Frogbit on the Zambezi river, October 2013.

A recent paper by Geoffrey Howard, Mike Bingham and Mark Hyde published in the journal BioInvasions Records flags up the risk of yet another invasive water plant species reaching the Kafue river basin and highlights the need for more records to monitor its spread and assess the threat to native wildlife.

The plant of concern is the Amazon Frogbit or South American Spongeplant Limnobium laevigatum  (Humb. & Bonpl. ex Willd.) Heine (Hydrocharitaceae), a native of South and Central America that superficially looks like water hyacinth (Eichhornia crassipes (Mart. Solms)(Pontederiaceae).

The first reports from Africa were between 2009 to 2012, when plants were discovered in wetlands and water bodies near Harare and then at the edge of Lake Kariba and on the Zambezi river further downstream. Some plants were also found in an outlying population near Kasama in the Northern Province of Zambia. To date it has not been found in the Kafue river basin.

Most likely to have been introduced through the aquarium trade, the Amazon Frogbit has also become invasive in other parts of the World, notably Australia and North America, crowding out other water plants and blocking channels as well as shading out submerged plants and aquatic animals that need light to thrive.

The name “spongeplant” refers to the spongy surface on the underside of its leaves. This increases buoyancy so that the plant can easily float and move with the wind and water current.  It may also move upstream and to new water bodies carried by boats and fishing gear or wildlife.   Superficially like water hyacinth, plants may be emergent, with roots, or entirely free-floating.

The paper flags up the need for more records to help assess the speed and dangers of invasion. The similarity in appearance to water hyacinth may mean it has been overlooked and be far more widespread than present records suggest. The Trust would welcome any geo-referenced photographic records from the region. Please send them to frogbit@kafuerivertrust.org.

Reference: Geoffrey W. Howard, Mark A. Hyde and Mike G. Bingham, 2016. Alien Limnobium laevigatum (Humb. & Bonpl. ex Willd.) Heine (Hydrocharitaceae) becoming prevalent in Zimbabwe and Zambia BioInvasions Records, 5, 4: 221-225.

Showing the spongy lower surface of young Amazon Frogbit leaves

Showing the spongy lower surface of young Amazon Frogbit leaves

 

Extensive growth of Amazon Frogbit downstream of Chief Chiawa on the Zambezi river, October 2013.

Extensive growth of Amazon Frogbit downstream of Chief Chiawa on the Zambezi river, October 2013.

 

 

 

What Future for the Kafue Lechwe?

Lechwe calf optReview: Shanungu G.K., Kaumba C.H. and Beilfuss R. 2015. Current Population Status and Distribution of Large Herbivores and Floodplain Birds of the Kafue Flats Wetlands, Zambia: Results of the 2015 Wet Season Aerial Survey. Zambia Wildlife Authority, Chilanga, Zambia.

The Kafue Flats make up a 6,500 km2 floodplain along the Kafue river that extends from Itezhitezhi for 400 km downstream to the head of Kafue Gorge. Once considered the most important agricultural entity in Zambia (Bingham 1982) and – with its huge herds of lechwe antelope and vast flocks of waterbirds – offering one of the greatest wildlife spectacles in Africa (Dowsett and de Vos, 1964), its value was severely damaged in the 1970s by construction of hydropower dams that regulate the natural flood.

Despite this change, the Flats remain the only refuge for the Kafue lechwe Kobus leche kafuensis, a distinct race of Red lechwe, and an important area for 12 globally threatened bird species, historically including the largest concentration of Wattled Cranes Bugeranus carunculatus in the World.

Thirteen aerial surveys to monitor the numbers of lechwe were carried out during the 1980s and 1990s. They showed that the lechwe population had fallen from about 94,000 before the floods were regulated to stabilise at around 49,000 in the ‘80s and ‘90s. Fewer counts of cranes were made and census estimates varied more widely, showing no significant change following flood regulation.

Since 2000 only two censuses of lechwe have been made, the last in 2005. The present census report is thus long overdue.

The survey, carried out in April 2015, aimed to map the distribution and census large mammals and birds, including lechwe, cattle and wattled cranes, and record human settlement. The report analyses trends over the past 45 years and discusses factors responsible for change. Recommendations are made to improve wildlife conservation and management.

The survey revealed a dramatic decline in the lechwe population since the census of 2005. Less than 30,000 are estimated to survive, the lowest ever recorded. The survey confirmed a 2005 finding, that the population decline has been greatest on the South bank in and around Lochinvar National Park. By contrast, the population of Wattled Cranes was estimated at 2,962, the highest count in more than 30 years, confirming the importance of this wetland for cranes.

Abundant evidence of human encroachment of the flats was found. Over 92,000 cattle were present in the survey area and cattle posts and fishing villages were observed widely across the landscape, many in the core areas for lechwe, cranes and other waterbirds.

The authors identify a number of possible factors causing the recent decline in lechwe including poaching and excessive hunting quotas, competition with cattle, and disease. However there can be little doubt that the decline in lechwe on the South bank is due to the encroachment of an invasive shrub, Mimosa pigra, that now excludes lechwe from much of its former range within Lochinvar National Park.

A number of management recommendations are made including:

  1. That the boundaries of Lochinvar and Blue Lagoon national parks be extended to create a single park that protects the floodplain between the two from human encroachment;
  2. That habitat restoration to reduce the impacts of invasive shrubs, such as Mimosa pigra and Dicrostachys cinerea, on lechwe, cranes and other wildlife is carried out. Measures should include the introduction of environmental flows from the dams to improve water conditions;
  3. That Park staff should be better equipped for management tasks, and
  4. That aerial surveys should be conducted bi-annually and research and monitoring work on species of conservation concern expanded.

The authors and sponsoring organisations are to be congratulated on presenting an attractive and publicly accessible report that will set the conservation agenda for years to come.

References

Bingham, M.G., 1982. The Livestock Potential of the Kafue Flats. Pp. 95-103. Proceedings of the National Seminar on Environment and Change: the Consequences of Hydroelectric Power Development on the Utilization of the Kafue Flats, Lusaka, April 1978.

Dowsett, R.J. and A. de Vos, 1964. The ecology and numbers of aquatic birds on the Kafue Flats, Zambia. The Wildfowl Trust Sixteenth Annual Report, 1963-1964. Pp. 67-73.

DOWNLOAD THE REPORT:   Shanungu et al., 2015. Current Population Status and Distribution of Large Herbivores and Floodplain Birds of the Kafue Flats

Common Myna – a new bird species for Zambia

Courtesy of Clement Tang

Courtesy of Clement Tang

On 30 October 2015 a pair of Common Mynas, Acridotheres tristis were found at a nest in the Nkanga River Conservancy near Choma by Daniel Green of Chenga Farm. This appears to be the first record of the species in Zambia. [See Postscript].

Common Myna is listed by IUCN – the World Conservation Union – amongst the ‘World’s 100 worst’ invasive alien species, sharing this dubious honour with only two other bird species [1]. Native to Asia, the Common Myna is an intelligent, adaptable, fearless starling that often lives in close association with people. An omnivorous scavenger, it feeds mainly on fruits, seeds and insects. It nests in cavities, often in buildings or trees, or in dense vegetation. Outside the breeding season the species may form noisy communal roosts numbering thousands in urban parks and gardens [2].

The Common Myna is now found on every Continent except South America and Antarctica. Colonisation of Africa by this species began in 1902 with the escape of some captive birds in Durban, South Africa. It is now abundant throughout much of South Africa and is spreading rapidly northwards. First seen in Botswana in 1975 it appeared in Zimbabwe in the early 1980s, Lesotho in 1994, Mozambique in 1997 and Namibia in 2004 [3]. In 2011 a pair bred in Hwange National Park [4], increasing to three pairs in 2014 [5]. It has been reported recently near Kazungula and in Kasane [6, 7].

It is widely believed the Common Myna competes with and eventually displaces local birds. However, adverse effects on indigenous wildlife in South Africa are poorly documented and most descriptions are of an anecdotal nature. In Botswana, Common Mynas have been observed sitting outside the nest holes of Red-billed Wood-hoopoe Phoeniculus purpureus, Red-billed Oxpecker, Buphagus erythrorhynchus and Amethyst Starling, Cinnyricinclus leucogaster preventing the adults from feeding their chicks, which starved to death [7]. In Zimbabwe, they successfully evict Crested Barbet, Trachyphonus vaillantii, House Sparrow, Passer domesticus and Red-billed Buffalo-weaver, Bubalornis niger from their nests [8].

BirdLife Zimbabwe cautions that the Common Myna is set to become a serious alien invader, posing a threat to some indigenous bird species [9]. The birds at Chenga Farm were shot, but their future colonisation of the Conservancy will threaten this stronghold of Zambia’s only endemic bird, the Zambian (Chaplin’s) Barbet, Lybius chaplini (see Post 12 February 2014 New funding for Zambian Barbet conservation).

Postscript

The first Common Mynas seen in Zambia now appear to have been single birds at Sinazongwe (Tertius Gous) and Livingstone (Rory McDougall) in October 2014.  (Rory McDougall, 14 November 2015).

Common Myna on Chenga Farm

Common Myna on Chenga Farm

References

[1] IUCN Invasive Species Specialist Group 2015. View 100 of the World’s Worst Invasive Alien Species

[2] Global Invasive Species Database. Acridotheres tristis.

[3] Peacock, D. S., Rensburg B. J. van and Robertson, M. P. 2007. The distribution and spread of the invasive alien common myna, Acridotheres tristis L. (Aves: Sturnidae), in southern Africa
South African Journal of Science, 103: 465-473.

[4] Facebook, 2015. Fans of Hwange National Park 17 August 2012.

[5] Zambezi Travel and Safari Company Zambezi Blog 21/11/14

[6] NewsDay 27 April 2013. Mynas may be a major threat!

[7] Tyler, S.J. 2015. Common Mynas continue to spread. Babbler 61: 39-40.

[8] Mundy, P. 2015. Common Myna – Report Presented to the BLZ AGM. The Babbler, Newsletter of BirdLife Zimbabwe. August/September 2015.

[9] The Standard, 13 April 2014. Exotic Myna bird causes problems.

Coat_of_arms_of_Zambia.svg[1]
Opening the National Assembly on 18 September 2015, President Edgar Lungu announced the Ministry of Agriculture and Livestock will be split into the Ministry of Agriculture, and the Ministry of Fisheries and Livestock [1]. Noting the rapid depletion of fish in rivers and lakes due to intensive and unsustainable harvesting he said Government would invest in sustainable management of the natural fisheries resources through restocking and working with the local communities in promoting sustainable fishing methods.
In addition, to encourage fish farming, government will establish fish hatcheries in each province and promote privately owned hatcheries. It will also establish community fish fingerling nurseries in each district and train 1,400 fish farmers in fish feed production. The aim is to produce 90,000 tonnes of fish from natural fisheries and 80,000 tonnes of farmed fish to achieve self-sufficiency in fish production within the next three years.

Some 300,000 people currently derive their livelihoods as fishermen and fish farmers, or as fish traders, processors and other service providers. Nevertheless about 45,000 tons of fish is imported annually [2, 3]. In the last 40 years output per fisherman has fallen by almost half and total annual output has consistently failed to exceed 70,000 tonnes, even in favourable years.

The state of Zambia’s fisheries reflects a failure to manage open-access resources operated by impoverished rural communities, resulting in their collapse [5]. Rapid population growth has increased competition for fishery resources leading to declining catches, disappearance of large valuable fishes, and the introduction of illegal, small-meshed active fishing gears. The concept of balanced harvesting with moderate effort has no relevance to these fisheries, where the lack of alternative livelihoods for small-scale fishers means they have no choice but to continue fishing despite dwindling returns. In some areas, co-management with local communities has potential for success (e.g. around Lochinvar National Park), but other fisheries are so severely depleted that there is no prospect for recovery without radical restructuring of exploitation patterns coupled with habitat restoration [4, 5]. Increasingly however the harmful effects of climate change are apparent. On Kariba for example, lower rainfall and higher temperatures result in smaller floods adversely affecting water levels, the stratification cycle, nutrient fluxes and the Kapenta fish production [6].

The state of the three important fisheries of the Kafue river basin – Kafue Flats, Lake Itezhi-tezhi and Lukanga Swamp – is typical, with the situation on the Flats perhaps the most in need of intervention and co-management agreements. Phenomenally productive, the Flats was once Zambia’s most important fishery, lying close to the line of rail and urban centres. Change came in the 1970s with completion of the dam at Itezhi-tezhi and regulation of the natural flood. The height of the dam was increased during construction so that extra flood storage would enable prescribed flood releases to be made in most years to mimic the natural flood. This was intended to help maintain the productivity of the fishery as well as dry season pasture for cattle, lechwe and other floodplain wildlife. However it is doubtful whether ZESCO has ever made these releases, in contravention of its licence. Instead, unseasonal and unexpected floods have been noted downstream, damaging floodplain productivity, wildlife and the livelihoods of people living there. More recently fears for the fishery have increased following the installation of turbines at Itezhi-tezhi. These will draw deoxygenated water from the bottom of the reservoir in the late dry season potentially killing the fish downstream (see Post December 2013 : Itezhi-tezhi hydropower discharge threatens Kafue Flats fishery).

Crayfish damage to gill net catch

Crayfish damage to gill net catch

The Nile tilapia, an alien species, escaped from a Nakambala fish farm and is now common on the Kafue Flats.

The Nile tilapia, an alien species, escaped from a Nakambala fish farm and is now common on the Kafue Flats.

The story from the Flats provides one further lesson for fishery management. In recent times, local fish farmers have released invasive Red-claw crayfish Cherax quadricarinatus and Nile tilapia Oreochromis niloticus into the Kafue river, perhaps damaging the fishery irreparably. The crayfish are of little commercial value but now spoil about a third of the fish caught by fishermen, while their catches are dominated by a single species, the Nile tilapia. Sustainable fishery management will thus require effective regulation of the fish farming industry if further harmful releases of alien species to unaffected lakes and rivers catchments are to be prevented.

The new Minister, Mr Greyford Monde, has been MP for Itezhi-tezhi since 2011, so will understand the problems. He faces a herculean task – we wish him well!

References:

[1] Post, 18 September 2015. President Edgar Lungu’s Parliament speech in full. http://www.postzambia.com/news.php?id=11461
[2] FAO Fishery Country Profile: Zambia 2006. (ftp://ftp.fao.org/FI/DOCUMENT/fcp/en/FI_CP_ZM.pdf)
[3] Lusaka Times, 5 August 2015. Zambia shouldn’t be importing so much fish-President Lungu (https://www.lusakatimes.com/2015/08/05/zambia-shouldnt-be-importing-so-much-fish-president-lungu/)
[4] Landell Mills, 2011. Elaboration of a Management Plan for the Kafue Fishery. Final Technical Report. Project Ref. N° CU/PE1/MZ/10/002. “Strengthening Fisheries Management in ACP Countries”. Project funded by the European Union.
[5] Tweddle, D., Cowx, I.G., Peel, R.A. and O.L. F. Weyl, 2015. Challenges in fisheries management in the Zambezi, one of the great rivers of Africa. Fisheries Management and Ecology, 22: 99-111.
[6] Ndebele-Murisa, M.R., Mashonjowa, E and Hill, T. 2011. The implications of a changing climate on the Kapenta fish stocks of Lake Kariba, Zimbabwe. Trans. Roy. Soc. South Africa, 66: 105-119. DOI: 10.1080/0035919X.2011.600352.

 

Fish trading in Lochinvar National Park disturbs wildlife and discourages tourists.

Fish trading in Lochinvar National Park disturbs wildlife and discourages tourists.

What Crab is that?

M1 Dorsal_opt Surprisingly perhaps, no-one has ever collected and identified crabs in Zambia before.  So unsurprisingly, no guide to their identification or occurrence exists. But thanks to a recent crayfish survey by the Trust the identity of the common crab in the river in Kafue National Park, so often the prey of Giant kingfishers, is now known.

Crabs were caught as bycatch in traps set for crayfish between Lake Itezhi-tezhi and the Mushingashi Conservancy; photographed by volunteer Eurig Jones, and released. The photographs were then sent to expert Neil Cumberlidge at North Michigan University in the USA for identification.

The crab was identified as the Single-spined River Crab Potamonautes spinosus previously known only from South Africa, Zimbabwe and Namibia. If you encounter crabs in the river basin, please send us photographs from above, below and front and we will try and have them identified.

 

US FlagThe following is a transcript of the press release from the US Embassy in Lusaka following a recent visit by the Ambassador, Eric Schultz, to Kafue National Park:

 

Reflections on My Trip to Kafue National Park – A Call to Action by United States Ambassador to Zambia Eric Schultz

April 22, 2015. Lusaka.

My visit this past week to Kafue National Park, the largest park in Zambia and the second largest park in all of Africa, was wonderful and alarming at the same time. I was very much looking forward to this visit because Zambian wildlife is one of my favorite features of your beautiful country. When I was Deputy Chief of Mission at our Embassy in Zimbabwe more than 10 years ago, it was the unique wildlife and ecosystem that sparked my family’s dream to return to southern Africa. But my trip to Kafue National Park, while pleasing to me as a nature-lover, was a wake-up call to the tragedy of wildlife poaching in Zambia. And it will take all of us working together to put an end to this devastating scourge.

Alarming Poaching Crisis
I had primed myself to view some of Zambia’s majestic elephants while I was at Kafue National Park but was disappointed not to see a single one. Later, in talking to Zambia Wildlife Authority (ZAWA) officials, to wildlife protection NGOs, and to community members in Kafue, I learned that the Kafue National Park and Game Management Area elephant population is estimated to have been cut almost in half over the past five years due to poaching. It is no secret that the poaching crisis has affected all of southern Africa and that poachers operate within Zambia’s borders. Informal surveys estimate there are no more than 2,000 elephants left within the park boundaries. The criminals who kill this most regal of Zambia’s creatures, taking only its tusks, should be sought out and prosecuted to the fullest extent of Zambia’s law. Zambia’s elephants, rhinos, and other treasured wildlife are for all Zambians to enjoy and appreciate. More, elephants and other wildlife can be a centerpiece of a thriving and profitable tourism industry, employing tens of thousands of Zambians, but only if that wildlife is well-protected.

Even as we drove along the Lusaka-Kaoma road, which lies inside the boundaries of the park, I couldn’t help but think of how Kafue National Park’s wildlife is at risk. Cars, buses, and trucks were speeding along the road. Later, when I talked to community members, I learned that it is not uncommon for leopards and other prized animals to be hit and killed by this speeding traffic.

Encroachment is also a major problem. At one point, ZAWA officials showed us settlements and farmland encroaching on the park boundaries and pointed to the deforestation this encroachment results in, reducing the habitat for the wildlife.

How can we reconcile the needs of human progress and development with the need to protect Zambia’s wilderness and keep its animals alive? The answer lies in tourism that creates jobs and revenue for the communities living near Zambia’s national parks and game management areas. This is also the answer to reducing poaching. These communities must see the wildlife for the precious and renewable resource it is.

An important part of my visit to Kafue National Park was meeting with ZAWA officials and seeing first-hand the challenges they face. Charged with managing a huge area, often with very few resources and limited manpower, these officers work long days in the bush, living under difficult conditions, yet remain highly committed. I congratulate ZAWA and its officers for their commitment and dedication to protecting Zambia’s wildlife under such harsh circumstances and in the face of rising poaching pressures.

But ZAWA can’t do it alone; it needs support from all of us. There are many organizations working hard to support ZAWA in the Kafue area, such as Game Rangers International, and I applaud them and others who have risen to this challenge. Now let’s get other community members, NGOs, the Zambian government, the international community, and others working together to support ZAWA’s efforts to protect wildlife in Kafue National Park and throughout the country.

Communities Must Benefit from Protecting Wildlife
Part of the challenge for elephants and other wildlife in and around Kafue National Park is that the local community does not appear to benefit at present from the protection of wildlife or from the tourism in the park. I was dismayed at the condition of facilities in a Game Management Area community close to the main entrance gate of the park. Together with community leaders, I visited a primary school with two small buildings and only four teachers serving more than 400 children! There were not nearly enough desks and chairs for all of the students, and the buildings were in desperate need of repair. Community members said the only financial benefit they have seen from the park in recent years was support received from hunting license revenues coming from the Game Management Area, not from tourism generated within the park itself. Hunting can play a positive role in conservation but tourism, by promoting the preservation of Kafue’s wildlife, can and should play a much bigger role in improving the welfare of the communities near the Park.

Community members in and around national parks must play an active, positive role if wildlife is to be saved from extinction and form the basis for a tourism industry from which all Zambians will benefit. ZAWA, NGOs, the Zambian government, and international community must engage with local communities to determine how Zambia’s parks and tourism can benefit local communities so that they are part of the wildlife protection solution. Despite Victoria Falls and some of the largest and potentially best national parks in Africa, Zambia attracts only a few hundred thousand tourists a year. It has the potential to attract millions who would contribute to the Zambian economy and to the benefit of all Zambians but most especially to the local communities that are home to this precious natural heritage.

The Time is Now
I encourage the government to look for new ways to support the communities around its national parks, and I encourage all stakeholders to work together with the Zambian government and communities to support their efforts.

We have a chance to turn the tragic poaching crisis trend around and for Zambia to establish a framework under which both local communities and the entire economy will profit from Zambia’s wilderness treasures for generations to come. But the time to act is now. Once elephants are nearly extinct or gone from Zambia, it will be too late. We must all work together with ZAWA to combat this crisis.

Reliable poaching statistics need to be regularly available so that we can properly address the challenge, and so that people around the world can be educated about the regional poaching crisis. By raising awareness, we can encourage additional funding to ZAWA, wildlife protection NGOs, and others so that we have a fighting chance to stop these crimes from continuing. In closing, I continue to be fascinated by Zambia’s natural beauty. Though we saw no elephants, on one game drive in the park we did spot a leopard. It was the highlight of the trip. This is what tourists pay to see: animals in their natural habitats. To experience Africa’s nature is what motivates people to fly to Zambia from across the world. This is Zambia’s greatest natural resource, which – if protected – can help provide a bright economic future for all Zambians.

 

Copyright: Louis Du Preez

Copyright: Louis Du Preez

Trustee Ben Tyser has now published findings from his research at Namwala in May and June 2010 investigating the importance of Red-claw crayfish Cherax quadricarinatus in the diets of eight species of predatory or omnivorous fish[1]. Crayfish were found in the stomachs of four predatory species: Sharptooth catfish Clarias gariepinus, Butter barbel Schilbe intermedius, Yellow-belly bream Serranochromis robustus and Thin-face largemouth Serranochromis angusticeps. The catfish C. gariepinus was the most important predator, with crayfish found in half the stomachs containing food. No crayfish remains were found in Three-spot tilapia Oreochromis andersonii, Large-spot squeaker Synodontis macrostigma, Purpleface latrgemouth Serranochromis macrocephalus or Western bottlenose Mormyrus lacerda stomachs, which are omnivorous.

The research did not examine the impact of this new food source on the relative abundance of predatory fishes. However invasive crayfish are powerful ecosystem engineers and studies following invasions elsewhere have chronicled dramatic changes. Clear water systems rich with a diversity of aquatic plants and animal life have become turbid species-poor systems dominated by phytoplankton, crayfish and a few vertebrate predators.

The spread of crayfish within the Kafue and Zambezi systems threatens the ecological integrity of 11 Wetlands of International Importance in six countries, including the World Heritage Sites of Lake Malawi and Okavango Delta, as well as the five most important freshwater fisheries of the region. The Trust intends to monitor the spread and impact of this invasion but needs your help and money to do so. Please report your sightings and/or send us a donation.

For a copy of Ben’s paper, or to report crayfish sightings, email crayfish@kafuerivertrust.org


[1] Tyser, A.B. and Douthwaite, R.J. 2014. Predation on invasive redclaw crayfish Cherax quadricarinatus by native fishes in the Kafue River, Zambia. African Journal of Aquatic Science, 39, 4, 473-477

 

Gwisho Hot Spring

Gwisho Hot Spring

First written in 1972 but then lost in obscurity, this informative guide has now been partially revised by the author Chris Legg, and made available on-line. Chris, the foremost expert on the hot springs of Zambia was working for the Geological Survey Department at the time.

The springs at Gwisho and Bwanda are a ‘must-see’ for any visitor to Lochinvar. Located on elevated ground on the edge of woodland in the south of the park, visitors have far-reaching views over the dambo grasslands to the north and the wildlife coming to drink at the springs. The guide explains why the springs are there, maps their location and describes the chemical composition and temperature of the spring waters.

A copy of the guide can be downloaded here.

By kind permission of Chriskut_flickr

By kind permission of Chriskut_flickr

Zambia Crane and Wetland Conservation Programme (ZCWCP): Project Summary

by Griffin K. Shanungu, Richard Beilfuss and Kerryn Morrison

The primary goal of the Zambia Crane and Wetlands Conservation Programme (ZCWCP) is to secure the crane populations and their wetland habitats through conservation action and the implementation of a long-term monitoring and research program. The framework of this project has evolved since its initiation in 2000 – 2003, under the then ICF/EWT African Wattled Crane Programme (AWAC). The main focus of that programme was to conduct intensive, nation-wide surveys of Wattled Cranes (Bugeranus carunculatus), Grey Crowned Cranes (Balearica regulorum), and other large waterbirds in all of the major wetland systems of Zambia. The work highlighted the global importance of Zambia for the conservation of both Wattled and the Grey Crowned Cranes.  Global population estimates for Wattled Crane are currently at 8,000 individuals.  At present, the Wattled Crane population in Zambia is estimated at 5,000 individuals, over 60% of the global population.

Three wetland ecosystems are considered strongholds: the Barotse floodplains (including Liuwa Plains National Park), with a population estimate of 1,900; the Kafue Flats, with a population estimate of 1,800, and the Bangweulu Swamps, with a population estimate of 1,000.  In addition, smaller numbers exist in many other wetlands including the Busanga Plains, Lukanga Swamps, and Chambeshi Swamps. In as much as the project highlighted the importance of these wetlands for crane conservation, little still is known about Wattled and Grey Crowned Crane ecology, movements, nesting and roosting sites, as well as the conservation threats they face. The newly re-established ZCWCP aims at addressing these gaps in knowledge and enhancing conservation efforts for the cranes throughout their range.

The project is anchored on five key components:

1)       Population surveys to better understand the status and distribution of cranes in Zambia.

2)       Basic and applied research to improve our understanding of crane ecology and to better manage and conserve their populations. Amongst other things, our research will include the inter-relationship between feeding grounds, water and grazing herbivores; and on breeding success under different conditions.

3)       Direct involvement in management such as invasive species control.

4)       Ecological monitoring linked to Eflows in support of the regional Zambezi River Basin Environmental Flows Programmme —indicator species.  For example, relationships between water conditions (timing, magnitude, duration, extent of water conditions) and Wattled Crane distribution and productivity. The ZCWCP will provide data on indicator species—Wattled Cranes, Kafue lechwe, and also Crowned Cranes.

5)       Assess ongoing and emerging threats in all important crane habitats in Zambia, including those related to human activities such as fishing at Liuwa, capture for illegal trade, powerline collisions, and especially mining (geothermal, gypsum).

The project will also focus on building capacity for local professional staff and students in crane research to ensure the sustainability of monitoring of cranes in Zambia.

Through partnerships with Zambia Wildlife Authority, WWF-Zambia, African Parks and other relevant conservation organizations in Zambia, ZCWCP will strategically position itself to influence management decisions that will directly benefit the long-term sustainability of cranes in Zambia. One of the emerging threats to cranes on the Kafue Flats is the spread of invasive alien plant species – most important and destructive being the Mimosa pigra. The woody species that is native to South America has resulted in negative impacts for waterbirds as well as herbivore populations.  The ZCWCP will play an important role in finding ways in which to reduce the spread of this species through supporting research that is aimed at finding cost effective methods of managing this invasion, as well as actively engaging local communities to physically remove the plants and retain the vast wetlands as productive land able to support biodiversity.

By focusing our efforts at sites important to cranes across Zambia, and by working collaboratively with key partners and relevant communities, we aim to secure the future for Zambia’s populations of cranes.

OLYMPUS DIGITAL CAMERA

Kingstone Moonga of the Department of Fisheries and Confred Musuka of the Department of Zoology and Aquatic Sciences at the Copperbelt University have recently published their findings following interviews with fishermen in Namwala District[1].

Most of the fishermen interviewed considered crayfish[2] a nuisance as they did not regard them as food.  Crayfish fed on fish caught in their gill nets damaging the catch and reducing its value.  Disentangling them sometimes damaged the nets and resulted in injury.

The numbers of crayfish caught showed strong seasonal variation with the highest numbers caught per finfish occurring in the hot season, and fewest in the cold season.  Numbers also depended on where the nets were set, with more caught in bottom set nets and fewest in top set nets, and more caught in nets set close to the shore than further out.

Interestingly, fishermen associated the arrival of crayfish with a decline in finfish catches and a reduction in crab abundance.

To download the full paper, click here



[1] Moonga, K. and Musuka, C.G. 2014.  The effect of accidentally introduced red swamp crayfish (Procambarus clarkia) in Kafue fishery.  International Journal of Agriculture, Forestry and Fisheries. 2 (1) 8-15.

[2] The crayfish is identified as Procamburus clarkia, a species that escaped from a fish farm near Kitwe in 1980-81, but not been recorded in the river since.  A second species, Cherax quadricarinatus, escaped from a fish farm near Kafue town about ten years ago. This species is now abundant on the Kafue Flats and has spread upstream to the Itezhi-tezhi dam wall and perhaps beyond.  More information on the distribution and identity of crayfishes in the river is sought by the Trust.