Title : A close analysis of the major cause of the loss of fish fauna and diversity in lake Malawi
Abstract:
Lake Malawi is the third largest fresh water lake in Africa and the ninth largest fresh water lake in the world. It contains more fish species than any other lake in the world. The diversity of these species is of special significant as most of them are endemic to Malawi. Apart from providing fish to the nation which is an affordable source of animal protein for a larger percentage of Malawi, the fisheries resources in Lake Malawi provide livelihoods to over 1.6 million people in Malawi. The fisheries sector in Malawi contributes approximately 4% to national Gross Domestic Product. About 85% of fish caught in Malawi comes from Lake Malawi. Of late it has been noted that this fresh water fish fauna and diversity is under severe threat by anthropogenic activities which is basically becoming worse in the light of devastating effects of climate change and high population growth.
Study Objective(s)
It is against this background that a study was conducted to explore and analyse major causes of the loss of fish fauna and diversity which includes a declining catch of traditional fishery in Lake Malawi.
Methodology
A qualitative prospective mixed method cohort study which involved interpretative literature review, focus group discussions, key informant interviews and in-depth interviews was carried out consisting a randomly selected sample of 62 respondents from Sengabay, Msaka, Chembe, Bolera,Moto,Kadango and Chikulo fishing beaches in Salima and Mangochi respectively. Apart from Senga Bay, all other study areas are within the South Eastern and Western Arms of Lake Malawi, which are basically the most productive part of the lake. The study respondents included members of Beach Village Committees, large scale commercial fishers as well as fisheries extension officers. Data analysis in the study which was carried out between March 2014 and November 2017 was being analysed on a continuous basis using tally sheets.
Key Findings
The study documented the following as some of the major causes of the loss of fish fauna and diversity in Lake Malawi.
- Destructive and illegal fishing: Over the years there has been an increase in the use of destructive and illegal fishing equipments. As if this is not enough, these equipments are being used in restricted fish breeding areas (spawning grounds) to the extent of sweeping the underwater vegetation that are great fish spawning grounds.
- Extensive Pollution: Excessive feeding in cages under Cage culture which is now in full practice in Lake Malawi is contributing to the accumulation of eutrofications/Nitrogen Phosphorus (N2) which eventually affects the fish fauna. Apart from this, because of the agricultural activities that are taking place in the upland which are catchment areas of some of the rivers that feeds Lake Malawi, in some cases the water is polluted with chemical fertilisers ,pesticides and other pollutants which eventually has an effect on the fish fauna and diversity in Lake Malawi.
- Over exploitation of fisheries resources/Overfishing: There is an increase in fishing efforts using modern and motorised equipments which include solar lamps hence a general increase in the numbers of fishing units on Lake Malawi is affecting the fisheries resources.
- Introduction of Exotic Species: Some exotic, non native/alien species that are basically meant for aquaculture and mariculture has been introduced in some parts of the lake either by design or default hence they have a potential of disturbing the life cycle of the fish fauna and its diversity in Lake Malawi.
- Effects of Climate Change: Just like other sectors climate change is negatively affecting the fish fauna and diversity in Lake Malawi by amongst others causing a drop in water levels in the lake as well as siltation bringing in negative changes in the ecosystem.
Conclusion
It is a fact that despite its economic and social importance, the Lake Malawi fish fauna is exposed to many manmade threats. Malawi’s economy is agro and natural resource based hence majority of Malawians relies on income derived from agriculture and natural resources which include fisheries as such the government and its development partners should reinvigorate their efforts in the protection, management and conservation of the fish fauna of Lake Malawi which is highly diversified.
Key words: fauna, diversity, pollution, fisheries, spawnin
What will audience learn from your presentation?
Will know major causes of the loss of fish fauna and diversity which includes a declining catch of traditional fishery in Malawi/Africa and the world at large. How to preserve fisheries resources,Use of recommended and sustainable fishing gear
Explain how the audience will be able to use what they learn?
Enforcement mechanism and develop mitigation measures
Is this research that other faculty could use to expand their research or teaching? YES
All the listed factors as major causes of the loss of fish fauna and diversity in Lake Malawi should be taken into consideration and be avoided at all costs in the fisheries programming
