Luis Tito de Morais

• PhD
• Research Director at Institute of Research for Development

relations taille-poids chez 20 espèces de poissons de l'estuaire de la Fatala en Guinée-conakry, afrique de l'Ouest. Les relations taille-poids ont été estimées pour 20 espèces de poissons collectées au cours de campagnes de pêche scientifique à la senne tournante et aux filets maillants, menées de janvier 1993 à mars 1994 dans l'estuaire de la Fat...

Infaunal communities descriptors (abundances, biomasses, traits) and environmental variables sampled in stations located in the Sine Saloum reverse estuary and the Fadiouth Lagoon in the Petite Côte region (Senegal, West Africa). Samples were collected both in the intertidal and the subtidal zones.

In West African tropical estuaries, such as the Saloum Delta (Senegal), mangroves provide specific socio-economic functions including various natural food resources for local human populations. Mangrove-habitat loss is therefore of great concern, in terms of conservation and management, and highlights the need to study West African mangrove under h...

Scientific fishing programmes were carried out between 1979 and 2013 in several West African estuarine, coastal and lagoon ecosystems. Batrachoides liberiensis represented only 5.2% of the occurrences, of which the majority were recorded in the Sine Saloum estuary. This originality makes it possible to use this population to characterise certain fe...

This study provides length‐weight relationships (LWR) that had not yet been reported for four fish species belonging to four different families: Chrysichthys johnelsi Daget, 1959, Cynoglossus senegalensis (Kaup, 1858), Citharichthys stampflii (Steindachner, 1894) and Pseudotolithus typus, Bleeker, 1863. Data were collected in the Fatala estuary, re...

relations taille-poids chez 20 espèces de poissons de l'estuaire du Sine Saloum au Sénégal, en afrique de l'Ouest. Les relations tailles-poids (rTP) ont été estimées pour 20 espè-ces de poisson collectées au cours des missions de pêches scientifi-ques effectuées d'avril 1990 à octobre 2012 dans l'estuaire du Sine Saloum, Sénégal, avec comme engin d...

Length‐weight relationships (W = aLb) were estimated for 5 fish species, the pearl stingray Fontitrygon margaritella (Compagno & Roberts, 1984), the West African spadefish Chaetodipterus lippei (Steindachner, 1895), the East Atlantic African spadefish Ephippus goreensis (Cuvier, 1831), the law croaker Pseudotolithus senegallus (Cuvier, 1830) and th...

relations taille-poids chez 19 espèces de poissons de deux réservoirs artificiels tropicaux (Manantali et Selingue) au Mali, en afrique de l'Ouest. Les relations longueur-poids (rLP) ont été estimées pour 19 espèces de poissons échantillonnées dans deux lacs artificiels (Manantali et Sélingué) au Mali : Brycinus leuciscus, B. macrolepi-dotus, B. nu...

Throughout the world, biodiversity and nature's contributions to people are under threat, with clear changes evident. Biodiversity and ecosystem services have particular value in Africa– yet they are negatively impacted by a range of drivers, including land use and climate change. In this communication, we show evidence of changing biodiversity and...

This paper describes a dataset of fish, crustacean and mollusc occurrences extracted from the “Experimental Fishing” section of the IRD's PPEAO information system. PPEAO stands for “Fish communities and artisanal fisheries of West African estuarine, lagoon and freshwater ecosystems”. This database contains information collected using two different...

Cet article vise à faire le point sur là où nous en sommes au niveau mondial en matière de production et de gestion des données sur la biodiversité. Le choix des données et des indicateurs à collecter en matière de biodiversité, y compris sur le plan de la socio-économie et de la description des relations hommes-nature, pose de multiples enjeux, à...

Bioaccumulation of toxic metal elements including mercury (Hg) can be highly variable in marine fish species. Metal concentration is influenced by various species-specific physiological and ecological traits, including individual diet composition and foraging habitat. The impact of trophic ecology and habitat preference on Hg accumulation was analy...

In the current study, ten elements contents (Fe, Zn, Mn, Cu, Cr, Co, Ni, Cd, Pb and Hg) have been measured in muscle and liver of four pelagic fish species (Engraulis encrasicolus, Sardina pilchardus, Scomber japonicus and Trachurus trachurus) from the north-west African coast (South Atlantic Moroccan coast), collected during summer and autumn seas...

This study examines the effects of increasing salinity on fish assemblage structure in the Casamance Estuary, Senegal, using a series of indices. The study data were derived from commercial fishery surveys conducted between April and July 2005. Analysis of within-trophic-group diversity in the Casamance Estuary shows a significant drop in the diver...

Impacted marine environments lead to metal accumulation in edible marine fish, ultimately impairing human health. Nevertheless, metal accumulation is highly variable among marine fish species. In addition to ecological features, differences in bioaccumulation can be attributed to species-related physiological processes, which were investigated in t...

Chapter published in The IPBES regional assessment report on biodiversity and ecosystem services for Africa, pp. 1-76

The status of marine biodiversity in the Eastern Central Atlantic (ECA), especially of coastal and pelagic fishes, is of concern owing to a number of threats including overharvesting, habitat loss, pollution, and climate change combined with inadequate policy responses, legislation, and enforcement. This study provides the first comprehensive docum...

The status of marine biodiversity in the Eastern Central Atlantic (ECA), especially of coastal and pelagic fishes, is of concern owing to a number of threats including overharvesting, habitat loss, pollution, and climate change combined with inadequate policy responses, legislation, and enforcement. This study provides the first comprehensive docum...

The presence of tropical species has been reported in Atlantic-European waters with increasing frequency in recent years. Unfortunately, the history of their migrations is not well understood. In this study, we examined the routes and timing of fish migrations in several ecosystems of the East Atlantic Ocean, combining several publicly available an...

Kinetics of accumulation and elimination in liver and muscle of two marine fish species, Dicentrarchus labrax, and Solea senegalensis, dietary exposed to 3.5 ppm dw of Cd are investigated. During 60 days, fish were fed with a prepared diet containing Cd, after which a 30 day depuration period was carried out. No significant impact of Cd on growth...

In order to investigate the TE composition of aerosols and quantify atmospheric deposition fluxes to the Canary Current Eastern Boundary Upwelling System (CC-EBUS), aerosol and bulk deposition samples were collected from three coastal locations in Morocco (Agadir, Laayoune and Dakhla) as part of the EPURE project (http://www-iuem.univ-brest.fr/epur...

In this study, we report the distributions of total dissolvable cadmium and particulate cadmium from 27 stations in southern Moroccan coastal waters (22°N–30°N), which is part of the North-West African upwelling system. These distributions were predominantly controlled by upwelling of the North Atlantic Central Waters (NACWs) and uptake by primary...

Aside from natural sources, marine ecosystems can be subjected to metal contamination due to urban effluents and industrial activities. Part of this metal exposition involves marine sediments, making the interface between water and sediment a gateway for contamination of marine organisms. In this study, the influence of trophic pathways on metallic...

The Canary Current Large Ecosystem is characterized by a major, nutrient-rich up-welling of deep, cold oceanic waters, which stimulates high biological productivity that results in an abundance of both pelagic and demersal fishery resources. In this area, the Moroccan coast is also under direct anthropogenic activities influences such as phosphates...

This work investigates the effects of changes in both fishing pressure and the environment on the trophic dynamics, abundance and diversity of species in the artisanal commercial fisheries off the northern coast of Senegal. Using artisanal commercial fishing data (provided by the Centre for Oceanographic Research of Dakar-Thiaroye [CRODT] in Senega...

Two indicators of fish exploitation, catch per unit effort (CPUE) and yield per unit area, were used with surveys of small‐scale fishery landings to compare two African reservoirs that differ in their level of fish exploitation, being high for Selingue Reservoir and low for Manantali Reservoir, both located in West Africa. The heavy exploitation in...

Diagnosis of the status of yellow mullet: Mugil cephalus and bluefish: Pomatomus saltatrix stocks on the north coast of Senegal is made from three biological indicators: percentage of mature fish, fish percentage of the optimal size and percentage of mega-spawners, using the size frequency of species on a data set from 2004 to 2009. The results ind...

As marine protected areas (MPAs) are increasingly being utilised as a tool for fishery management, their impact on the food web needs to be fully understood. However, little is known about the effect of MPAs on fish assemblages, especially in the presence of different life history and ecological traits. Modelling the observed changes in fish popula...

There is a critical need to document the long-term variability of the West African Monsoon (WAM) in the Sahel region. We present here a multidecadal proxy record of the past hydrology from AD 460 to 1090 in the Saloum Delta, Senegal. The Saloum Delta is a hypersaline estuary where the salinity and the water isotopic composition are highly sensitive...

The utility of taxonomic and functional approaches in assessing the structure of fish communities is tested in the hypersaline estuary of the Casamance river using data from surveys of commercial fisheries conducted between April and July of 2005. Both taxonomic and functional diversity decrease from downstream to upstream regions of the estuary. I...

Two techniques, the conventional purse seine method and a novel method using vertical hydroacoustic surveys at fixed positions, were applied simultaneously in the Gambia River estuary to sample a fish population. Environmental parameters were measured simultaneously. Four surveys were performed during different hydrological seasons to reflect the m...

Two techniques, the conventional purse seine method and a novel method using vertical hydroacoustic surveys at fixed positions, were applied simultaneously in the Gambia River estuary to sample a fish population. Environmental parameters were measured simultaneously. Four surveys were performed during different hydrological seasons to reflect the m...

Based on three case studies of MPAs: the Port-Cros and Bouches-de-Bonifacio MPAs in the Mediterranean sea (France) and the Bamboung Bolong MPA in Senegal (Eastern Atlantic), we showed that trophodynamic models are useful tools to assess the effects of MPAs at the ecosystem scale. For each MPA, we first developed an Ecopath model, representing the f...

Marine protected areas (MPAs) are now viewed as an efficient tool to fight against the global deterioration of habitats and fish populations. However their efficiency and effects on the whole trophic network are little known. Based on the Bolong de Bamboung (Sénégal) case study, the objective of this study is to assess the impact of a MPA on the en...

Des modèles écosystémiques pour évaluer les effets des AMPs : démarches et enseignements du projet Amphore

Ecomorphological correlates were sought among 10 fish species of different life history traits in a tropical estuary. Results from gut contents analysis showed that fish species were classified into four trophic groups including detritivores, zooplanktivores, benthivores, piscivores and macrocarnivores. Resource partitioning among fishes was under...

Ecomorphological correlates were sought among 10 fish species of different life history traits in a tropical estuary. Results from gut contents analysis showed that fish species were classified into four trophic groups including detritivores, zooplanktivores, benthivores, piscivores and macrocarnivores. Resource partitioning among fishes was under...

http://www.colloque-scientifique-amp.fr/IMG/pdf/14-Poster_Colleter_gascuel.pdf

Presentation at the conference: ”Contribution des aires marines protégées à la gestion éco systémique des milieux et de leurs usages : quelle stratégie scientifique ?”, National Museum of Natural History (MNHN), Paris, France

West African tropical estuaries play an important role in the growth and survival of many commercially exploited fish species and enable the sustainability of considerable artisanal fishery yields. However, their trophic functioning remains poorly understood. In the Sine Saloum estuary (Senegal), a marine protected area (MPAs) was designated in 200...

Le barrage anti-sel de Maka a été érigé en 1998 sur le fleuve Casamance (Sénégal) afin de rétablir les conditions dulçaquicoles au profit de l’activité rizicole des populations locales. Il sépare deux environnements de salinité contrasté : une partie aval salée sous influence de l’estuaire inverse et une partie amont d’eau douce. L’étude comparativ...

Trophic indicators were used to compare two Malian freshwater reservoirs whose main differences are based on their different fishing pressures. Data were collected from a scientific survey of small-scale fishery landings conducted in 2002/2003. The trophic levels of fish species caught by artisanal fisheries are estimated from observations of scien...

To investigate the changes in the fish assemblage of the Sine Saloum estuary (Senegal) over a 10-year period, it was surveyed during a complete hydrological cycle (three principal hydro-climatic seasons) first in 1992 and then in 2002-2003. The sampling protocol for the two surveys was identical, using the same sampling technique, the same collecti...

Fish communities living within the artificial reservoirs of Manantali and Selingue in Mali are compared after the monitoring of small-scale fishery landings over 13months (May 2002–June 2003). The fishing pressure constitutes the main difference of these two similar reservoirs. The effects of fishing on the structure of the fish communities are ana...

La majorité des études scientifiques ayant pour objet la définition de l’état de santé d’un écosystème, impose de faire référence à des peuplements et des populations de poissons vivant dans un environnement non stressé. Face à l’anthropisation croissante des écosystèmes aquatiques estuariens et continentaux, la définition d’un tel peuplement de ré...

Les peuplements de poissons de l’estuaire du Sine Saloum (Sénégal) ont été échantillonnés durant un cycle hydrologique complet (3 saisons caractéristiques) d’une part en 1992, d’autre part en 2002-2003. Le protocole d’échantillonnage est resté strictement le même pour ces deux périodes : même technique d’échantillonnage, même mise en œuvre, mêmes p...

The gastric evacuation (at 11 oC and 19 oC) and the relation between prey size and fish size of juveniles of Buglossidium luteum and Arnoglossus thori (Pisces, Heterosomata) are studied. The fish were collected at 20 m depth in the Banyuls Bay (France, Western Mediterranean). B. luteum showed a very rapid evacuation rate at 19 oC (2h to 4h for a Ig...

Lack of reliable data on the fisheries of northern Côte d'Ivore reservoirs is a major limitation for management of the fish stocks. As individual reservoirs cannot be studied due to the high costs and lack of trained investigators, empirical and production models have to be used to evaluate exploitation rates and fisheries potential. Daily yield (D...

A comparative study, combining three different assessment methods (fish gillnet sampling, artisanal fisheries surveys and hydroacoustics) was conducted in Mali where two man-made reservoirs (Sélingué and Manantali) are particularly suited for investigating the impact of fishing effort on the fish assemblage. These two ecosystems have relatively sim...

Les petits barrages constituent une composante désormais incontournable des paysages d'Afrique de l'Ouest. Petits et nombreux, mais dispersés, ils structurent les espaces, en générant un ensemble de ressources diverses. Ils induisent de fait la juxtaposition d'acteurs et d'usages souvent complémentaires, parfois concurrents, éventuellement antagoni...

Les petits barrages constituent une composante désormais incontournable des paysages d'Afrique de l'Ouest. Petits et nombreux, mais dispersés, ils structurent les espaces, en générant un ensemble de ressources diverses. Ils induisent de fait la juxtaposition d'acteurs et d'usages souvent complémentaires, parfois concurrents, éventuellement antagoni...

Les travaux portent sur une étude de suivi par enquêtes des pêches artisanales réalisée par l'Idessa en 1994 sur 4 petits barrages du nord de la Côte d'Ivoire, puis sur son extension à 9 retenues entre 1996 et 1998. Des pêches expérimentales (filets maillants et senne) ont alors été parallèlement réalisées sur 5 d'entre elles. Ces diverses sources...

Les petits barrages représentent une part importante des ressources en eau pérennes du nord de la Côte d'Ivoire. Ils correspondent à ce titre à un outil important pour l'aménagement du territoire ivoirien. Sur le plan halieutique, ces retenues constituent une source non négligeable de production de poissons (entre 7,0 et 22,4 t km-2 an-1, DA COSTA...

A comparative study of the Ebrie lagoon (Ivory Coast) and Lake Nokoue (Benin) was made based on ecotrophic model outputs that describe each system's structure and functioning. Two models were constructed using the Ecopath software to differentiate main biomass flows in the systems. Results indicate that biomasses and productions in both ecosystems...

Estimate the impact of the fishery pressure on a fish population is an important current goal for the research programs. The present work takes place in such a frame, applied to lacustrine environment. The experiments were performed in two contrasted Malian lakes, from the ex-ploitation point of view. Facing the difficulty to get historical series,...