Campagne Rythnic 07/05/1980 - 15/05/1980: résultats des chalutages pour l'étude des variations nycthémérales d'abondance des espèces démersales de Côte d'Ivoire

As explained in the title, this campaign aimed to assess the diurnal vertical variations in abundance of demersal species off the Côte d'Ivoire

Importance de certaines caractéristiques biologiques dans la structuration génétique des espèces de poissons: le cas de Ethmalosa fimbriata et Sarotherodon melanotheron

Six populations of Ethmalosa fimbriata and six of Sarotherodon melanotheron have been analysed using enzymatic electrophoresis. The study of gene flow intensity in these two species indicate that: - In Ethmalosa fimbriata, a migratory species with high fecundity and pelagic eggs, there is a high gene flow between populations (3 Nm 83). - In Sarotherodon melanotheron, a sedentary and mouthbrooder species with low fecundity, there is a low gene flow between populations (1 Nm 4).

Notes sur quelques poissons d'espèces nouvelles ou peu connues des eaux douces Cambodgiennes

The ichtyological research, conducted in Cambodia from 1938 to 1939 by the Oceanographic Institute, has greatly enriched the Indochinese freshwater wildlife inventory. 40 new species for Indochina were harvested. They have been divided into 12 families and 30 genera, 12 new species for Indochina. The 7 completly unknown species described in this note are: Clupea (Alosa) Thibaudeaui, Xenocheilichthys Loppei, Cosmochilus Pellegrini, Kryptopterus Cheveyi, Pangasius altifrons, Cybium cambodgiensis, Synaptura krempfi.

La pêche artisanale en lagune Aby (Côte d'Ivoire): analyse des captures en 1988 et 1989

The exploitation of fish stocks in Aby lagoon was marked by an increase of total fishing effort, yields and therefore by the increase of total production. Fishing effort evolution was due to: the increasing of the number of beach seines which has increased from 26 in 1987 to 32 in 1988, the reappearance of syndicat seines and finally the importance of fishing teams activity.

Suivi cartographique de l'expansion des macrophytes envahissant le système lagunaire Ebrié (Côte d'Ivoire)

Remote mapping were realised from December 1986 to September 1989 to describe the seasonal evolution of macrophytes colonizing the surface waters of the eastern sector of the Ebrié lagoon. The vegetal cover of this sector and associated lagoons is essentially composed of Eichhornia crassipes (water hyacinth). Its expansion is favored by the decrease in the salinity of the lagoon waters which is due to rain falls. Its migration through the lagoon environment is ensured by the overflow of the Comoé river. The opening of the Bassam inlet induced its temporary disappearence from the newly created estuarian zone.

Les macrophytes aquatiques des berges lagunaires

This synthetic article describes the composition and organization of vegetations colonizing the Ebrié lagoon banks and provides original data on the recent evolution of this association consecutively to the accidental introduction of 2 new species of floating macrophytes (Salvinia molesta and Eichhornia crassipes).

La pêche industrielle des poissons démersaux en Côte d'Ivoire. Généralités, localisation, homogéneité relative des zones de pêche ivoiriennes

This paper describes the fishery of Côte d'Ivoire and its evolution to the present day. The location of fishing off Côte d'Ivoire is specified for each area and each type of trawler. A comparison of productivity between the different areas shows disparities that allow to make clearer the repartition of effort of all types of trawlers in each area. The Côte d'Ivoire continental shelf is populated with demersal stocks of homogeneous densities.

Note sur l'évolution des populations de Copépodes pélagiques de l'upwelling mauritanien (mars-avril 1972)

The evolution of a plankton copepod population in the Mauritania upwelling was studied by following a drogue for 9 days, from the point of upwelling till the water-mass dives under offshore waters. The Shannon index of specific diversity and the tropic structure allow separation into several stages in the studied succession. The upwelling brings near the shore a rather poor, highly diverse fauna, with a low filter-feeder rate. The phytoplanktonic development induces an increase in the copepod number. The filter-feeders become dominant and the diversity decreases. When the increase of copepod number stops, the diversity decreases and the omnivore and carnivore rate increases.

État des stocks pélagiques côtiers en Côte d'Ivoire

Evolution of catch and catch by unit effort of the sardine fishing boats (purse seiners) has been examined from 1966 to 1975. The effort data has been calculated with a new computer programme: Crosardi (Soisson et Barbe, 1974). The analysis has been done on the whole stock and in more detail on the east and west stocks of Côte d'Ivoire. The Sardinella eba stock has been analysed separately. Those analyses were done using the general production model (Prodfit; Fox, 1974). The stock of the eastern area of the Côte d'Ivoire seems to be exploited at its maximum level. Nevertheless, the western area stock could be able to support a progressive increase of fishing effort.

La végétation terrestre des collines de Cauda (Nhatrang)

The comparative study of the vegetation of the hills of Cauda, in their unprotected and protected parts shows that on the unprotected part the vegetation is of the maquis type with the absence of the arborescent stratum and the shrub stratum is often spiny. On the contrary the protected part presents a development of the arborescent stratum; but the floristic composition of the two parts is not very different many species are identical. The evolution towards the climax seems slow on these rhyolite hills with the semi-protection.

Note additionnelle sur les espèces de Chlorodopsis (Brachyures)

The present paper completes the authors’ studies (1958) on the species of Chlorodopsis of Viet-Nam. It gives observations on the new specimens collected previously and of a new species. It exposes the results of the observations on specimens communicated to the authors by the Museum of Paris, the Indian Museum of Calcutta and the Bishop Museum of Honolulu. These specimens include the syntypes of Chl. melanochira and Chl. Woodmasoni and some samples of another species not yet recorded on the Viet-Nam seashores. The taxonomic position of various species is revised and species maintained by Balss (1938) in the genus Pilodius are included in the genus Chlorodopsis. The authors give a new key to separate all the species of the genus Chlorodopsis.

Observations sur les premiers pléopodes males d'espèces d'Actea (Brachyures) du Viêt-Nam

Few observations on the first male Pleopode of the genus Actea are available. Examining the possibility of using their characteristics for a taxonomic work, the authors expose the obtained data on the subject and describe the Pleopods of 18 species of Actea collected on the Viet-Nam seashores. A tentative to define the different types of Pleopods gives a new argument to consider and recognize the genus Banareia as a distinct genus of Actea.

Les espèces de Carpilodes (Brachyura-Xanthidae) du Viêt-Nam

The authors have identified 18 species of the genus Carpilodes, collected on the Viet-Nam sea shores; three species and one variety are new. A key for the identification of the thirty species and two varieties of the genus is associated with the description of the new forms. The pleopods 1 of the male for the great part of the species identified in Viet-Nam sea shores are figured.