U6CAU Proceedings Volume 1, Number 1, 67 - 71, September, 2019 Maiden Edition on Harnessing African Potentials for Sustainable Development, , Nigeria ISSN 1596-1273 ABUNDANCE AND DISTRIBUTION IN THE GREAT KWA RIVER, NIGERIA

1Asuquo, Philomena Edet and 2Ifon, Honor Tajoes* 1Institute of Oceanography, University of Calabar, Calabar, Nigeria 2Department of and Environmental Biology, University of Calabar, Calabar, Nigeria *Corresponding Author: [email protected]

ABSTRACT are well distributed within the Neo-tropical and Afro-tropical bio-geographic zones. In Afro-tropics, they are found to be widespread in freshwaters including rivers, streams, lakes and dams. In this study, the general objective was to examine their relative abundance and distribution in the Great Kwa River, Nigeria. A one-year monthly sampling for cichlids was undertaken from November 2017 to October 2018 with local traps, hook and line as well as multi-mesh gillnets that ranged between 30 mm to 80 mm. Relative abundance and t-distribution test were used respectively to examine the abundance and distribution of cichlid species in the two sites of the river. Results showed that a total of 587 individual cichlids were caught from Esuk Anantigha (60.99%) and Esuk Atu (39.01%). Species collected include Oreochromis niloticus (45.14%), Tilapia zillii (36.46%) and guntheri (18.40%) in order of abundance. Independent t-test revealed significant seasonal and spatial disparities in relative abundance and distribution at P<0.01. Higher cichlid abundance was observed during dry season with distribution skewed towards Anantigha station. Thus, there is need to control anthropogenic activities in the area to ensure sustainable biodiversity and conservation of aquatic resources. Key words: Relative abundance, species distribution, cichlids, freshwater, Great Kwa River

INTRODUCTION including plants, insects, detritus, fish Cichlids are well distributed within bio- eggs/larvae and other smaller fishes, algae, geographic zones of the tropics including the phytoplankton and zooplankton. While some Neo- and Afro-tropics. In Afro-tropical species are strictly specialists, others eat more countries like Nigeria they are found to be than one food category, others are widespread in freshwaters including rivers, opportunistic feeders. Fish abundance in their streams, lakes and dams. According to Cabej habitats is as a results of food availability and (2019), up to 3000 fish species ore more have abundance as well as the types of substrate of been described worldwide from the family that habitat (Greshishchev et al., 2015). Cichlidae making them the largest group According to Olopade and Dienye (2018) among the vertebrates. Of these, at least 1100 habitat use by some fish species especially cichlid species have been reported in cichlids including feeding, resting and (Stefanie et al., 2019) with only 12 species in reproduction is strongly correlated with spatial Nigeria (Olopade and Dienye, 2018). and temporal changes in habitat conditions Although most species especially ornamental such as physicochemical parameters. Habitat cichlids are found in East Africa notably Lake stability also depends on ecosystem structure Malawi, Lake Victoria and Lake Tanganyika, which is determined by the types of interaction West Africa is competitively a repository of whether predation, mutualism or competition cichlid species (Kinyage and Lamtane, 2018). among co-species (Mougi and Kondoh 2012). Cichlids are noted for their very active In terms of human activities, the major threats swimming and feeding behaviours. They are to river systems throughout the world as also aggressive in nature and can be territorial, observed by Joadder et al. (2015) and Galib et especially during mating. Cichlids eat a variety al. (2018) are pollution, destruction of of food materials in their natural habitats supporting riparian, alteration of flood plain

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ABUNDANCE AND DISTRIBUTION OF CICHLIDS Part A: Science, Engineering and Technology Asuquo and Ifon 2019 ecosystems, invasive alien species, from the popular hills at Oban in Aningeje overexploitation of biotic resources and community, Southern State, climate change. The Great Kwa River, an Nigeria and discharge into the Gulf of Guinea important river that supports the livelihood of through the Cross River Estuary roughly at the Calabar people through fisheries and non- latitude 4°45ʹN and longitude 8°20ʹE (Akpan, fisheries activities has been overtime subjected 2000). The eastern coast of the Calabar to constant anthropogenic pressure ranging municipal L.G.A. is drained by the lower from dumping of untreated wastes to reaches of the river (Fig.1). Human activities unregulated sand mining as well as within the river include fishing, sand mining, overexploitation of the riparian vegetation. farming, lumbering. Calabar does not have This could be responsible for declining fish standard waste treatment facility, as such populations. On this note, the present study is untreated waste are dumped directly into the designed to examine the abundance and river which could affect biodiversity. distribution of cichlids between major landing Collection of Samples sites of artisanal freshwater fishery of the Fish samples were collected from two stations Great Kwa River, , Nigeria. – Atu (Station 1) and Anantigha (Station 2). A Study Area 12-month fish sampling which took place from The Great Kwa River is a major tributary of November 2017 to October 2018 using local the Cross River Estuary. Other sister traps, hook and line as well as multi-mesh tributaries are the Calabar, Cross and Akpa gillnets that ranged between 30 mm to 80 mm. Yafe Rivers. According to Akpan (2000), the Great Kwa River flows in southward direction

Fig. 1: Map of Great Kwa River indicating the two sampling stations (Atu and Anantigha). Source: Eyo et al. (2013)

Fresh fish samples collected from the field Laboratory, University of Calabar, Nigeria. In were preserved in ice chest and transported to the laboratory, species were identified the Zoology and Environmental Biology according to Froese and Pauly (2017). The

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ABUNDANCE AND DISTRIBUTION OF CICHLIDS Part A: Science, Engineering and Technology Asuquo and Ifon 2019 identified fish specimens were further grouped niloticus and T. Zillii were recorded throughout and counted. Data were recorded in the months of study, whereas C. guntheri was spreadsheets and saved for statistical analysis. observed only in seven months from November 2017 to May 2018 which could have been the Statistical Analysis reason for the lowest abundance as it accounted Data were analysed using “ecostat” indices for only18.40% of the total catch. O. niloticus such as relative abundance and independent t- had its peak in February, T. zillii in December distribution test which examined respectively while C. guntheri peaked in January (Fig. 2). the abundance and distribution of cichlids in The observed abundance of cichlids in the dry the two sites of the river. seasons could be due to less turbid water status of the Great Kwa River in period of less or no RESULTS AND DISCUSSION rain. This could be attributed to the fact that Results showed that a total of 587 individual cichlids are more associated with clear than cichlids belonging to three species of different turbid waters as reported in the work of genera were caught during the study (Table 1). Kinyage and Lamtane (2018). Habitats with More abundance was recorded in Esuk high water transparency increases visibility and Anantigha (60.99%) than Esuk Atu (39.01%). foraging abilities of the cichlids, hence high Species collected include Oreochromis preference contrary to turbid habitats. The niloticus (45.14%), Tilapia zillii (36.46%) and present findings also support the previous Chromidotilapia guntheri (18.40%) in order of record of Allin et al. (1999) who reported abundance. Monthly distribution of cichlids relationship of fish diversity and density with obtained during the study showed that O. water clarity.

Table 1: Percentage distribution of cichlids in the Great Kwa River, Nigeria (November 2017 to October 2018) Station/ Esuk Anantigha Esuk Atu Pooled data Tcal Species N % N % N % Oreochromis niloticus 159 27.09 106 18.06 265 45.14 3.32*

Tilapia zillii 133 22.66 81 13.80 214 36.46 5.41*

Chromidotilapia guntheri 66 11.24 42 7.16 108 18.40 2.87*

Total 358 60.99 229 39.01 587 100

*Significantly different at P<0.01, t-distribution in table of values=2.2

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ABUNDANCE AND DISTRIBUTION OF CICHLIDS Part A: Science, Engineering and Technology Asuquo and Ifon 2019

35.00

30.00

Orechromis niloticus

25.00 Tilapia Zillii Chromidotilapia guntheri 20.00

15.00

Relative Relative abundance(%) 10.00

5.00

0.00

Months

Fig. 2: Monthly relative abundance of cichlids in the studied river (November 2017 to October 2018) CONCLUSION landscape disturbance on The study on the abundance and distribution communities in Lake Tanganyika, of cichlids in the Great Kwa River has East Africa. Conservation Biology, revealed significant seasonal and spatial 13: 1017 – 1033. disparities (P<0.01, T-test) in cichlids Cabej, N. R. (2019). Epigenetic Principles of Evolution. 2nd edition, Science prevalence in riverine systems. Higher Direct. 783-806. DOI: relative abundance was recorded in the dry https://doi.org/10.1016/C2017-0- season while higher density was observed in 00736-X. Anantigha than Atu station. The study Eyo, V. O., Andem, A. B., Ekpo, P. B. therefore recommends controlled (2013). Ecology and Diversity of anthropogenic activities in the area to ensure Zooplankton in the Great Kwa River, sustainable biodiversity and conservation of Cross River State, Nigeria. aquatic resources. International Journal of Science and Research (IJSR), 2 (10): 67-71. REFERENCES Froese, R. & Pauly, D. (2017). Species of Allin, S. R., Cohen, A. S., Bills, R., Cichla: in FishBase. October 2017 Gashagaza, M. M., Michel, E., version. Tiercelin, J. J., Martens, K., Covelier, Galib, S. M., Mohsin, A. B. M., Parvez, T., P., Mboko, S. K., West, K., Lucas, M. C., Chaki, N., Arnob, S. Soreghan, M., Kimbadi, D. and S., Hossain, I. & Islam, M. N. (2018). Ntakimazi, G. (1999). Effects of Municipal wastewater can result in a

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ABUNDANCE AND DISTRIBUTION OF CICHLIDS Part A: Science, Engineering and Technology Asuquo and Ifon 2019 dramatic decline in freshwater fishes: a lesson from a developing country. Knowledge and Management of Aquatic Ecosystem, 419, 37. Greshishchev, V., Onikura, N. & Iyooka, H. (2015). Environmental factors influencing fish species distribution in irrigation channels around Ariake Sea, Kyushu, Japan. Irrigation & Drainage Systems Engineering (IDSE), 4:139. doi:10.4172/2168-9768.1000139. Joadder, M. A. R., Galib, S. M., Haque, S. M. M. & Chaki, N. (2015). Fishes of the river Padma, Bangladesh: Current trend and conservation status. Journal of Fisheries, 3(2):259-266. Kinyage, J. P. H. & Lamtane, H. A. (2018). Diversity and Abundance of Ornamental Cichlids at Katonga in Lake Tanganyika. Tanzania Journal of Agricultural Sciences, 17 (1): 17-22. Mougi, A. & Kondoh, M. (2012). Diversity of Interaction Types and Ecological Community, Science, 337(349): 1-5. DOI: 10.1126/science.1220529. Olopade, O. A. & Dienye, H. E. (2018). Distribution and abundance of cichlids in the New , Nigeria. Journal of Fisheries, 6 (2), 617–622. Stefanie, B. R. P., Melanie, A., Alexander, F. C., Ulrich, K. S., Bettina, R. (2019). New fossil cichlid from the middle Miocene of East Africa revealed as oldest known member of the Oreochromini. Scientific Reports, 9 (1). DOI: 10.1038/s41598-019-46392-5.

Cite as: Philomena Edet Asuquo and Honor Tajoes Ifon (2019). Cichlid abundance and distribution in the Great Kwa river, Nigeria. In: Asuquo, Francis E. (Editor) on Harnessing African Potentials for Sustainable Development, Calabar, Nigeria, September 2019; UNICAL Press & GIS Publishers. U6CAU Proceedings (Maiden Edition ) Volume 1, Number 1, 67 – 71.

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