Onchocerciasis Control Programme in West Africa: a 20-year monitoring of fish assemblages

Paugy, Didier; Fermon, Yves; Abban, K.; Diop, Moussa Elimane; Kassoum, Traore

doi:10.4000/books.irdeditions.28638

Cited by 4 publications

(4 citation statements)

References 12 publications

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“…To evaluate the possible short- and long-term effects of insecticide application on non-target fauna, a biomonitoring program was set up between 1974 and 2003 covering 50,000 km of river and including 11 West African countries. The biomonitoring results demonstrated little effect on fish [ 54 ] and macroinvertebrate taxonomic and functional composition [ 55 , 56 ].…”

Section: Biological Assessment Of Riversmentioning

confidence: 99%

The Biological Assessment and Rehabilitation of the World’s Rivers: An Overview

Feio

Hughes

Callisto

et al. 2021

Water

122

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The biological assessment of rivers i.e., their assessment through use of aquatic assemblages, integrates the effects of multiple-stressors on these systems over time and is essential to evaluate ecosystem condition and establish recovery measures. It has been undertaken in many countries since the 1990s, but not globally. And where national or multi-national monitoring networks have gathered large amounts of data, the poor water body classifications have not necessarily resulted in the rehabilitation of rivers. Thus, here we aimed to identify major gaps in the biological assessment and rehabilitation of rivers worldwide by focusing on the best examples in Asia, Europe, Oceania, and North, Central, and South America. Our study showed that it is not possible so far to draw a world map of the ecological quality of rivers. Biological assessment of rivers and streams is only implemented officially nation-wide and regularly in the European Union, Japan, Republic of Korea, South Africa, and the USA. In Australia, Canada, China, New Zealand, and Singapore it has been implemented officially at the state/province level (in some cases using common protocols) or in major catchments or even only once at the national level to define reference conditions (Australia). In other cases, biological monitoring is driven by a specific problem, impact assessments, water licenses, or the need to rehabilitate a river or a river section (as in Brazil, South Korea, China, Canada, Japan, Australia). In some countries monitoring programs have only been explored by research teams mostly at the catchment or local level (e.g., Brazil, Mexico, Chile, China, India, Malaysia, Thailand, Vietnam) or implemented by citizen science groups (e.g., Southern Africa, Gambia, East Africa, Australia, Brazil, Canada). The existing large-extent assessments show a striking loss of biodiversity in the last 2–3 decades in Japanese and New Zealand rivers (e.g., 42% and 70% of fish species threatened or endangered, respectively). A poor condition (below Good condition) exists in 25% of South Korean rivers, half of the European water bodies, and 44% of USA rivers, while in Australia 30% of the reaches sampled were significantly impaired in 2006. Regarding river rehabilitation, the greatest implementation has occurred in North America, Australia, Northern Europe, Japan, Singapore, and the Republic of Korea. Most rehabilitation measures have been related to improving water quality and river connectivity for fish or the improvement of riparian vegetation. The limited extent of most rehabilitation measures (i.e., not considering the entire catchment) often constrains the improvement of biological condition. Yet, many rehabilitation projects also lack pre-and/or post-monitoring of ecological condition, which prevents assessing the success and shortcomings of the recovery measures. Economic constraints are the most cited limitation for implementing monitoring programs and rehabilitation actions, followed by technical limitations, limited knowledge of the fauna and flora and their life-history traits (especially in Africa, South America and Mexico), and poor awareness by decision-makers. On the other hand, citizen involvement is recognized as key to the success and sustainability of rehabilitation projects. Thus, establishing rehabilitation needs, defining clear goals, tracking progress towards achieving them, and involving local populations and stakeholders are key recommendations for rehabilitation projects (Table 1). Large-extent and long-term monitoring programs are also essential to provide a realistic overview of the condition of rivers worldwide. Soon, the use of DNA biological samples and eDNA to investigate aquatic diversity could contribute to reducing costs and thus increase monitoring efforts and a more complete assessment of biodiversity. Finally, we propose developing transcontinental teams to elaborate and improve technical guidelines for implementing biological monitoring programs and river rehabilitation and establishing common financial and technical frameworks for managing international catchments. We also recommend providing such expert teams through the United Nations Environment Program to aid the extension of biomonitoring, bioassessment, and river rehabilitation knowledge globally.

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Section: Biological Assessment Of Riversmentioning

confidence: 99%

The Biological Assessment and Rehabilitation of the World’s Rivers: An Overview

Feio

Hughes

Callisto

et al. 2021

Water

122

View full text Add to dashboard Cite

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“…1988), fish communities were surveyed in several localities. Paugy et al . (1999) showed no detectable influence on fish communities by the insecticides used to control the populations of the aquatic stages of the onchocerciasis vector (a blackfly, Simuliidae, Diptera).…”

Section: mentioning

confidence: 99%

Spatial synchrony in population dynamics of West African fishes: a demonstration of an intraspecific and interspecific Moran effect

Tedesco

Hugueny

Paugy

et al. 2004

Journal of Animal Ecology

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Summary1. Synchronous fluctuations of the abundance of several populations at a regional scale can be a sign of a climatic effect on their dynamics (Moran effect). However, the interpretation of spatial synchrony is often complicated by the interaction between climatic disturbances and migrations between the studied populations. 2. We addressed this question by studying 24-year time-series of abundance estimates for four populations of four fish species in three different catchment basins in Côte d'Ivoire (West Africa). As localities from two different basins cannot exchange individuals, dispersal cannot be considered a synchronizing factor in this system. 3. A sign test performed on the four site × site correlation matrices rejected the null hypothesis of no spatial synchrony. No relation was detected in relating the level of synchrony in species dynamics ( r = 0·58 on average) to the geographical distances between the four sites (176-367 km). A more detailed analysis taking account of sampling error was carried out between two sites, and confirmed the above results. When corrected for sampling noise, high values of spatial synchrony were obtained ( r = 0·88 on average). 4. Interspecific spatial synchronies ( r = 0·57 on average) were almost as high as intraspecific values, suggesting that the four species are reacting in the same way to the same Moran effect. 5. A good correlation ( r = 0·54) between a regional river discharge index and the total catch of the four species 1 year later was observed, suggesting that hydrological variability is one of the main synchronizing factors. Moreover, as expected on theoretical grounds, spatial synchrony in river discharge ( r = 0·84 and 0·88 on a log scale) is similar to spatial synchrony in population dynamics ( r = 0·88 on average and corrected for sampling error).Key-words : disconnected populations, hydrology, Moran effect, sampling error, within and between species synchrony.

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“…Schilbe intermedius (Schilbeidae) is a catfish widespread in almost all Africa, which can reach a very substantial size of 50 cm or more (Lévêque, 1994;De Vos, 1984;Paugy et al, 1999). It has good economic value and is particularly prized for the quality and fineness of its flesh (Fermon, 2010;Bills et al, 2010).…”

Section: Introductionmentioning

confidence: 99%

Effect of Dietary Protein on Growth

Tossavi

Djissou

Ouattara

et al. 2020

ija

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The captive breeding of the Silver catfish Schilbe intermedius was envisaged to promote the aquaculture and to reduce the overfishing of this endangered species. S. intermedius fingerlings were fed various dietary protein levels to investigate their growth performance, feed utilization and carcass proximate composition. Fish meal and casein were the sources of protein used in the study. Six isocaloric experimental diets containing 25%~60% crud protein (CP) diet have been fed to three-replicate six groups of forty ( 40) fishes (mean weight: (1.640±0.015) g) for 8 weeks. Both percent weight gain and feed efficiency ratio significantly increased with increasing dietary protein levels up to 45%, while there were no significant differences for protein levels from 45 to 60%. Growth performances and nutrient utilization parameters of fingerlings fed different diets varied significantly (p < 0.05) and the highest growth performance and nutrient utilization were obtained with fish fed on a 45% CP diet. The second order polynomial regression between dietary protein and specific growth rate (SGR) indicated that protein requirements of S. intermedius fingerlings ranged from 42.5 to 53% of diet. The highest protein content of the fish carcasses was found in fish fed 45% dietary protein and there was not significantly different (p > 0.05) with that of fish fed 60% dietary protein. Lipid content increased with increasing dietary protein levels. The dry matter and protein content of the initial sample were significantly higher (p > 0.05) than the values after feeding the fish with experimental diet.

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Onchocerciasis Control Programme in West Africa: a 20-year monitoring of fish assemblages

Cited by 4 publications

References 12 publications

The Biological Assessment and Rehabilitation of the World’s Rivers: An Overview

The Biological Assessment and Rehabilitation of the World’s Rivers: An Overview

Spatial synchrony in population dynamics of West African fishes: a demonstration of an intraspecific and interspecific Moran effect

Effect of Dietary Protein on Growth

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