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The lake Alau f sheries of the North East zone of Nigeria, Maiduguri conta ns relatively low fish species exp oited artisanal y by 365 f shers in al the samp ed stat ons. Station 4 has the highest mean number of fishers (275 ± 21.30) while station 2 has the least mean number (35 ± 9.30). A total of one thousand, eight hundred and thirty one (1831) fish specimens were sampled. The major fish species were from the families; Characidae, Cichlidae, Mochokidae, Schilbeidae, Mormyridae, Cyprinidae, Clariidae, Bagridae, Centropomidae, Polypteridae and Osteoglossidae. The most dominant family observed was the Cichlidae. The species composition recorded was 28 in all the studied stations. Heterotis niloticus was dominant with mean number of 40.4 ± 1.1.28 and percentage composi on of 11.2 %. Sex ratio of 1 male to 0.95 female was recorded for Heterot s niloticus. Multi gears fishing were observed. The percentage composition o fishing gears observed were in the order of clap net (33 %), cast net (20 %), gill net (20 %), long line (11 %), Mali trap (15 %) and seine net (1 %). There was a steady increase in number of fishers employing nets of various kinds. Lake Alau fisheries can be rated as over fished due to the pressure of fishers and the quality of the r catches.

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The species composition, abundance and distribution of molluscs population together with some physico-chemical variables from five different stations in the littoral region of lake Alau, Maiduguri Borno state, were studied from October 2001 to September 2002. Three patterns of seasonal abundance were found, maximal abundance during the rainy season (July-September), moderate abundance during the harmattan season (November-February) and minimal abundance in the dry hot season (March-June). Significant dif erences in species composition and abundance of the molluscs were found between stations studied. The total number of organisms recorded was 3368 comprising of 1924 Bivalves and 1544 Gastropoda. 8 families were recorded which includes Bithyniidae, Hydrobiidae, Lymnaeidae, Physidae, Valvatidae, Vivipariidae, Sphaeridae and Unionidae while 15 species were observed in this study. The predominant families in terms of total number collected from all stations Sphaeridae and Unionidae recording 1006 and 933 organisms with the percentage compositions of 29 86% and 27 7%. The least was from the families Lymnaci dae w h ota number of 116 and 3.44% as the percentage composi on. The abundance of the molluscs was positively and significantly correlated at 5% confidence with temperature (r = 0.675), dissolved oxygen (r = 0.832), phosphate (r = 0.528).

The Diversity of fish species, composition and abundance from Bodna River in Kwali Area Council, Abuja was studied between May 2018 to April 2019.The aim of the study was to determine the management and sustainable use of the fisheries resources of the Area council. About 1331 fish were collected from the artisanal fishermen during the study period and morphometric indices were determined using standard methods. The fish were identified and counted. Sex ratio 1:2:1 (Males to Females) was obtained indicating a male dominated population. Length –weight measurement indicated that the fish exhibited positive allometric growth pattern. The highest percentage abundant species in the site were Oreochromis niloticus with 34.8% Clarias garienpinus with 28.0% and Pellonula leonensis with 17.6% and the least occurring species were Nannocharax shariensis with 11.0% Mormyrus valenciensis with 7.7%. The seasonal variation of fish distribution was observed to be higher in the wet season with 66.2% than the dry season. Nutrient displayed greater impact on fish abundance in the wet season. The Simpson and Shannon Weiner’s diversity index values were (0.976) and (-1.456) in both richness and evenness respectively. The findings of the study could be helpful to the artisanal fishermen and the community for fisheries sustainability.