Capture-based aquaculture of Clarias catfish: case study of the Santchou fishers in western Cameroon
Victor Pouomogne
Institute of Agricultural Research for Development
Foumban, Cameroon
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Pouomogne, V. 2008. Capture-based aquaculture of Clarias catfish: case study of the Santchou fishers in western Cameroon. In A. Lovatelli and P.F. Holthus (eds). Capture-based aquaculture. Global overview. FAO Fisheries Technical Paper. No. 508. Rome, FAO. pp. 93–108.
SUMMARY
Aquaculture is an expanding activity in Cameroon. The limited availability of high quality fingerlings and feeds has been identified as one of the factors constraining its further development. Following the failure of government owned stations to meet this demand, effort is being put into seed production in private hatcheries. However, wild caught seed remains important, especially Clarias species seed caught in the Nkam River basin in the western and littoral provinces of Cameroon.
This report presents a review of Clarias jaensis and Clarias gariepinus in Cameroonian capture-based aquaculture, with a focus on the market chain and socio-economic and environmental challenges related to the collection and use of juveniles of these species from the wild. The data and information presented here derive from research undertaken in participation with the fishers of the Nkam Valley in Western Cameroon under the Construction de l’Innovation Piscicole (CIP) project (Annex 1). Specific exchanges with key stakeholders involved in the fishery were conducted from January to March 2007.
Clarias spp. are silurid fish with interesting features for aquaculture. Clarias gariepinus appears as the most promising on account of its faster growth. However, it does not reproduce spontaneously in captivity, and hatchery operators need to induce spawning through injection of gonadotropic hormones. In addition, high mortality is observed in the early stages of the life cycle and relatively intense management is required to achieve high survival rates of fingerling in ponds, particularly with regards to reducing predation and cannibalism and ensuring the availability of adequate live feed needed during the larval phase. These constraints are currently being addressed through participatory research with Cameroonian fish farmers.
In the Nkam Valley, annual flooding provides millions of catfish juveniles that are collected by fishers and fish farmers for direct consumption or restocking of flooded ponds extensively used by farmers in traditional aquaculture. The collection of juveniles, along with the harvesting of flood ponds, takes place from November to March when the dry season results in the flooded rivers receding from farmed lowlands.
As aquaculture expands in the region, farmers from the highlands are now also seeking catfish juveniles, and a new economic activity has emerged to supply Clarias gariepinus fingerlings of homogenous sizes to buyers. This requires new inputs from the fishers including: sorting of species and sizes, handling the fish with greater care, stocking and nursing them in controlled rearing structures and better marketing. Of the many aspects affecting the survival of wild caught catfish in ponds, the two following were identified as critical: how long the fish remain in the mud during pond draining, and the water exchange rate during stocking and transportation.
In 2006, about 10 tonnes of catfish were harvested from flood ponds. Over 300 000 Clarias jaensis were collected and distributed for aquaculture, along with almost 50 000 Clarias gariepinus. In addition to fish consumed in the household (31 percent) or given to relatives (34 percent), estimated cash revenue of US$20 000 were received by the 100 fishing households under investigation.
Compared to farmers in areas around the urban centre of Yaounde, farmers of the Nkam Valley appear to be consuming 10 times more fish. Most fishers were married (75 percent), with an average of 7 persons in the household. The relatively high literacy rate (>70 percent beyond primary school) provides the potential for training in sustainable management of the resource.
To improve the value of the catfish fingerling harvest to both collectors and consumers, it is recommended that fishers are: 1) trained in proper fish handling, and 2) ensure purchase and use of appropriate farming and handling equipment through some form of revolving credit plan. The positive influence of traditional beliefs of the Mbo people on the sustainable management of the fishery, both wild juveniles and broodstock for aquaculture purposes, is also discussed in the report.
INTRODUCTION
Catfishes of the genus Clarias (Siluroidei, Claridae) are widespread in tropical Africa and Asia (Sudarto, 2007). Clarias gariepinus is by far the most cultivated. However, as they do not normally reproduce spontaneously in ponds, Clarias catfish culture is constrained by seed availability. Induced breeding has been developed, but production systems and hatchery management techniques that make catfish seed of good quality readily available to all farmers are yet to be established in most African countries (Pouomogne, Nana and Pouomegne, 1998; Brummett, 2007). In these conditions, seed from the wild remains an important opportunity, when available.
The use of catfish seed from the wild for typical pond aquaculture is not documented in Africa. However, a number of reports have described the traditional practice of enhancing the natural entry of wild fish into flood ponds, such as the “fingerponds” in Lake Victoria wetlands (Unesco-IEH, 2005), and “whedoes” used in Benin and Togo (King, 1993). These traditional aquaculture facilities can be owned by individuals or communities. Due to their location in wetlands, they are often not able to be drained and are typically harvested by intensive capture fishing as water recedes at the end of the dry season, and are sometimes referred to as “amplified fisheries” rather than aquaculture (Mikolasek, Massou and Allagdaba, 2000; Dorey et al., 2002).
This paper focuses on African catfishes, specifically the use of wild-caught Clarias jaensis and Clarias gariepinus for aquaculture in the western Cameroon highlands. Although aquaculture production based on this practice remains marginal in Cameroon, this case highlights the interplay between the protection of the environment, poverty alleviation from well-managed inland fisheries and the gains to the overall society when rights of minor native groups are respected.
The study is based on secondary sources of information and data derived from published papers and unpublished reports. The author is part of an action research team working with farmers in the study area since 2003 through numerous projects
Capture-based aquaculture of clarias catfish: case study of the santchou fishers in western Cameroon 95
Figure 1
Clarias spp. Right – Clarias gariepinus and Clarias jaensis;
Left – Clarias catfish harvested from flood ponds
sponsored by the Ministry of Research and Innovation in Cameroon (MINRESI) and the French international cooperation agency. For the specific needs of the present study, additional primary source data and information were also collected from the field through interaction with fishers (see details on CIP project in Annex 1).