Investigated Taxa
Studies on fish assemblage in the Niger Delta Basin have been carried out by several researchers in the Niger Delta areas and its connecting creeks. (Scott, 1966; Chinda and Osuamkpe (1994) reported 57 species from 25 Families (Bonny River); Alison et.al. (1997) 22 Families (Upper Bonny River); Sikoki et al. (1998) 15 families (Nun River); Alfred-Ockiya (1998) 11 species (Kolo Creek River); Sikoki et al. (1999) 11 families (Brass River) and Ezekiel et al., (2002) reported 25 species in the New Calabar River. Some of the reported harvested families include Albulidae, Anabantidae, Aridae, Bagridae, Carangidae, Channidae, Cichlidae, Characidae, Cichlidae, Citharinidae, Clariidae, Clupeidae, Cynoglossidae, Cyprinidae, Cyprinodontidae, Dactyloprediae, Daysyatidae, Gobiidae, Gymnarchidae, Haemulidae, Hepsetidae, Lutjanidae, Malapteruridae, Mochokidae, Mormyridae, Mugilidae, Nandidae, Notopteridae, Osteoglossidae, Pantodonitdae, Phractolaemidae, Polypteridae, Rajidae and Sciaenidae
The checklist of fish and shellfish species recorded during the field visit in the study area showed that the Family Aridae, Carangidae, Clupeidae, Crassosteidae, Gobidae, Haemulidae, Lutjanidae, Mugilidae, Muricidae, Penaeidae, Polynemidae, Sciaenidae and Squalidae appeared extensively in the catchment water as indicated in Table 4.3.9.2 The Family Clupeidae included species such as Illisha africana, Ethmalosa finbrinata, Sardinella eba and S. modenerrhi. Virtually all the recorded species were well distributed in the area. Some of the caught fish species are shown in Plate 4.3.9.1.5a-e
Table 4.3.9.2.: Checklist of sighted and reported Fish species from the Area
S/N Family Scientific Name Common Name
Economically Important 1 Acanthuridae Adioryx hestatus
2 Albulidae Albula vulpes Lady fish X
3 Ariidae Arius heudeloti Marine catfish X
4 Bagridae Chrysichthys nigrodigitatus Grey catfish X
5 Callionymydae Canary drum
6 Carangidae Caranx carangus Horse eye mackerel 7 Carangidae Caran hippos
8 Carangidae Carangoides chrysophrys Threadfin jackfish 9 Carangidae Galeodies decadactylus Threadfin
10 Carangidae Vomer septinis
S/N Family Scientific Name Common Name
Economically Important 11 Carangidae Selarcru menopthalmus Jackfish
12 Carangidae Vomer setapinnis Moon fish
13 Cichlidae Oreochromis rukwa
14 Cichlidae Pagellus ehrenberyi
15 Cichlidae Sarotherodon galilaeus 16 Cichlidae Sarotherodon malanotheron 17 Cichlidae Tilapia heudeloti
18 Cichlidae Tilapia guineensis
19 Cichlidae Tilapia zillii X
20 Citharinidae Citharinus citharus
21 Claroteidae Chrysichthys nigrodigitatus
22 Clupeidae Ethmalosa fimbricata Bonga X
23 Clupeidae Ethmalosa dorsalis X
24 Clupeidae Ilisha africana Shad X
25 Clupeidae Sardinella eba Flat sardine X
26 Clupeidae Sardinella modenerhi Flat sardine X
27 Congridae Corvica nigrita
28 Cynoglossidae Cynoglossus senegalensis Tongue sole 29 Dactylopteridae Cephalocuthus volitan Flying gurnard 30 Daysyatidae Dayatis margarita Sting ray 31 Ephippidae Chaetodipterus goreensis Spade fish 32 Ephippidae Drepane africanus Spade fish 33 Gerreidae Eucinostomus malanopterus
34 Gobiidae Periopthalmus papilio Mudskipper 35 Haemulidae Pomadasys jubeleni Grunter
36 Haemulidae Pomadasys peroteti
37 Haemulidae Pomadasys rogerii Pigsnout Grunt 38 Haemulidae Pomadasys commersonnii
39 Lutjanidae Lutjanus goreensis Red Snapper X
40 Lutjanidae Lutjanus campenchanus X
41 Lutjanidae Lutjanus dentatus X
42 Lutjanidae Lutjanus agennes X
43 Monodactylidae Monodactylus sebae
44 Mugilidae Mugil babanensis Banana mullet X
45 Mugilidae Mugil cephalus X
46 Mugilidae Mugil falcippinnis X
47 Polynemidae Galeoides decadactylus Shine nose X
48 Polynemidae Polydactylus quadrifilis Royal threadfish 49 Polynemidae Pentanemus quinquarius
50 Pomadasyidae Pomadasys jubelini Common grunter X
51 Pomadasyidae Diagramma macrolepsis Big lip grunt X
52 Rajidae Raja miraletus Ray
53 Scaridae Sciana umbra
54 Sciaenidae Pseudotolithus elongatus Longnose Croaker X
55 Sciaenidae Pseudotolithus senegalensis X
56 Sciaenidae Pseudotolithus typus Nigerian croaker X
57 Sciaenidae Pseudotolithus epipercus Golden fish croakers X
58 Sciaenidae Umbirina canariensis Shortnose croaker X
59 Scombidae Scomberomorus japanicus Mackerel X
60 Serranidae Serranus aranus X
61 Sphyraenidae Sphyreana sphyreana Barracuda X
S/N Family Scientific Name Common Name
Economically Important
62 Sphyraenidae Sphyraena guachancho Barracuda X
63 Squalidae Squalus fernandinus Shark (dogfish) X
64 Stromateidae Stromateus fiatola
65 Trichiuridae Trichiurus lepturus Silverfish/Cutlass fish X 66 Trypterygilidae Umbrina cunariensis
SHELL FISH
1 Crapsidae Sesarma huzardi Hairy Mangrove crab
2 Crassostreidae Crassos trenagascar Mangrove oyster 3 Gecarcinidae Cardisoma armatum Rainbow crab
4 Muricidae Thais callifera Whelk
5 Ocypodidae Ocypodia Africana Ghost crab
6 Ocypodidae Uca tangeri Fiddler crab
7 Palaemonidae Macrobrachium vollenhovenii
8 Palaemonidae Nematopalaemon hastatus White shrimp 9 Palaemonidae Nematopalaemon maculates
10 Penaeidae Parapenaeopsis sp Shrimp
11 Penaeidae Penaeus kerathurus Shrimp
12 Penaeidae Penaeus notialis Shrimp
13 Potamidae Tympanotonus fuscatus Periwinkle 14 Potamidae Tympanotonus auratus Periwinkle 15 Portunidae Callinectes amnicola
16 Portunidae Callinectus anoniaala Swimming crab 17 Portunidae Callinectus marginatus
18 Thiaridae Pachymelania aurita
19 Balanus sp
19 Clibanarius africana Hermit crab
The size ranges of the various species varied in the different fishing grounds. Croaker Pseudotolithus elongatus varied between 15–60 cm in samples within the adjacent mouth of the ocean fishing ground, 10–54 cm in Bonny Estuary, 10– 42 cm in the creeks and creeklets.
In general, the size ranges in the ocean fishing grounds were higher than those along the creeks and creeklets. The most abundant sizes of commercially important species encountered comprised mostly of juveniles. The most abundant sizes for Sardinella maderensis, Ethmalosa fimbriata, Ilisha africana, Cynoglossus senegalensis, and Pseudotolithus elongatus were 10, 15, 18, 35 and 40 cm respectively. For Pomadasys jubelini, Polydactylus quadrifilis, Pseudotolithus typus and Pseudotolithus senegalensis were 10, 15, 20 and 25cm respectively.
There were more catches made from fishing grounds in the ocean compared with fishing grounds in the estuary; rivers and creeks based on the catch per unit effort from these fishing grounds. The highest catch per unit effort from the ocean was estimated at about 275 kg/trip/day while the catch per unit effort in the creeks and creeks fishing ground it was about 92 kg/trip/day.
Plate4.3.9.1.a: Species of Cynoglossus senegalensis, Trichiuru sleptorus and Pseudotolithus elongates and Arius hendeloti
Plate4.3.9.1.b: Fish species of, Ethmalosa finbrinata, Pseudotolithus elongates Galeoides decadactylus and Ilisha africana
Plate4.3.9.1.c: Local method for processing crayfish and prawn
Plate4.3.9.1.d: Processed and smoked crayfish and fish displayed in the local market
Plate 4.3.9.1.e: Balanus sp attached to mangrove plant and harvested periwinkle in a sack Tissue Studies
The results of the histopathological assessment of the tissue of Tilapia guineensis (fish) is presented in Plate 4.3.9.2.
Gill
Muscle and cartilage
Plate 4.3.9.2. Photomicrographs of Tilapia fish
Fisheries economics
i. Fishermen population: - The fishermen population could not be estimated during the survey, however, from the interview conducted, the fishermen are made up of mainly of Ogonis, Ijaws, Efiks, Ibibios, Yorubas/Ilajes and Ibos. Most of them are full-time fishermen.
ii. Fish Marketing and Processing: The fishes caught by the fishermen are sold fresh or processed (Figure by smoking and to fishmongers or transported to Ette and Ibeno Market within the State or to Oil Mill Market (Port-Harcourt) in Rivers State.
iii. The shellfish component plays a key role in the diet and economy of the people of the area.
iv. About two-third of the fish species recorded in the area could be classified as commercial.
Among the big commercial ones are the croakers (Pseudotolithus senegalensis and P.
elongates), bongas (Ethmalosa timbricate and E. finbricata), , mullet (Mugil babanensis), the sea catfish (Arius sp) and the Cutlass fish (Trichiurus lepturus), crayfish and periwinkle.
v. In general catch both by number and by weight is much lower in the rainy season than in the dry season according to the fishermen interviewed.
Potential fish yield and catch statistics
Agriculture occupies a prominent position in the national economy, contributing about 39%
of GDP and employing more than 65% of the population. It is the main source of food and raw materials supply to the country’s teeming population and industries. Ninety percent of Nigeria’s agriculture comes from peasant farmers who reside in the rural areas (Inoni and Oyaide, 2007).
Nigeria's fish production data has reflected that 5,788,474 tonnes of fish had been produced between 2010 and 2015 (NBS 2017). Year 2014 recorded the highest tonnes of fish produced with 1,123,011 tonnes; the second highest tonnes of fish produced were recorded in 2015 while the least were recorded in 2010 (Table 4.3.8.1.6). Coastal and brackish water fisheries contribute between 42.07% and 75.96 %, while the balance was from industrial fisheries and aquaculture.
Nigeria, like many other countries in sub-Saharan Africa, is endowed with substantial marine and inland fisheries resources, upon which the fisheries sector is based. However, production trend in the sector has been very unstable particularly, in the coastal/brackish water artisanal sector which provides the bulk of the domestic production. It is a common knowledge that fish catch in the Niger Delta has been on the decline. This was first noticed in the early 1970s when it was attributed to the civil wars (NEDECO, 1980). But this declining trend has continued up to date. The local people have often implicated environmental pollution resulting from oil and gas exploitation in the area. It should be noted that over fishing, population increase and use of small size nets and chemicals has played a leading role in fish decline.
Table 4.3.9.3: Nigeria's Fish Production: 2010 -2015 (metric tonnes)
S/N SECTOR SUB-SECTOR YEAR
2011 2012 2013 2014 2015 1 Artisanal Coastal & Brackish
Water
346381 370918 418537 435384 382964 Inland: Rivers &
Lakes
292105 297836 326393 324444 311903 SUB-TOTAL 638486 668754 744930 759828 694487 2 Aquaculture
(Fish Farm)
SUB-TOTAL 221128 253898 278706 313231 316727
3 Industrial (Commercial Trawlers)
Fish (Inshore) 19736 27977 37652 29237 10727 Shrimp (Inshore) 13749 17654 22219 20715 4737
EEZ - - - - -
SUB-TOTAL 33485 45631 59871 49952 15464
GRAND TOTAL 893099 968283 1083507 1123011 1027058
Source: NBS (2017) Fish Handling
Fish handling involves transportation, processing, preservation and marketing. The study area constitutes both part-time and full-time activity. The fishermen and members of their family are engaged in fish handling. Fishes for processing and preservation may be gutted or merely washed in water for drying (Figures 4.3.8.1.5c). Large size fishes are gutted, washed and are
either preserved whole or cut into two or more pieces. Small fishes and most juveniles are washed and preserved without gutting. Smoke-drying over fire is the most common form of fish preservation. Fishes to be dried are spread out on raised platforms or altars and energy for drying is obtain from wood (Figures 4.3.8.1.5d).
There is ready market for fresh and processed fish in Bonny Island main jetty and Market.
Fish mongers are at hand to buy fresh fish or arrange for smoke-drying and subsequently sell to consumers in and around the fishing settlement and to markets outside the area. Fresh, smoke-dried and live fish kept in baskets, tins and plastic containers are transported to markets in either Bonny Main Market or Port-Harcout City. Smoke-dried fish are packaged in bags, baskets or carried in basins for marketing.
4.4 Terrestrial Biodiversity Studies 4.4.1 Biodiversity Studies Introduction
Oil-rich regions are facing great and increasing impacts, including those resulting from, habitat destruction and changes in biodiversity. The increasing impact of human activities on coastal ecosystems requires great effort for the assessment of their ecological quality.
Performance Standard 6 recognizes that protecting and conserving biodiversity, maintaining ecosystem services, and sustainably managing living natural resources are fundamental to sustainable development. To investigate impact of habitat modifications on biodiversity and to support the present study, a review of literatures on flora and fauna resources of the region were carried out. The reviewed literatures on flora resources of the region include: Keay (1989), Adegbehin & Nwaigbo (1992), Okafor et al (1994), FORMECU (1999), Carroll &
Turpin (2002), Osuji & Ezebuiro (2006), Ndukwu & Edwin-wosu (2007), Olusola and Oluwatoyin (2009), Ebigwai et al (2014), Ebigwai & Akomaye (2014) while the available literatures on fauna resources include Moses (1985), FORMECU (1999), Ezealor (2002) SPDC (2004), Abere and Ekeke (2011), Udoidiong & Ekwu (2011). The findings from the reviewed literature for flora and fauna are as presented in Table 4.4.1.1 and Table 4.4.1.2 respectively.
Table 4.4.1.1: Floristic Resources Reviewed for the Coastal Niger Delta S/N Freshwater Swamp
Forest
Mangrove Forest Lowland Rain Forest
Modified habitat 1 Alstonia congensis Rhizophora racemose Khaya ivorensis Chromolaena
odorata 2 Symphonia globulifera Avicinnia nitida Lovoa kleineana Puereria
phaseoloides 3 Cleistopholis patens Ecastophyllum
brownie
Lophira procera Phyllantus spp 4 Anthonotha
macrophylla
Hibiscus tiliaceus Lovoa trichiloides Aspilia africana 5 Carapa procera Rhizophora harrisonii Pterygota
macrocarpa
Nephrolepsis biserrata 6 Pterocarpus mildraedii Papsalum vaginatum Sterculia Alstonia boonei
tragacantha 7 Pistia stratioites Avicinnia germinans Triplochiton scleroxylon
Costus afer
8 Ficus spp Ipomoea pescarprae Alstonia boonei Newbouldia laevis 9 Berlinia auriculataa Nymphaea lotus Cocos nucifera Sidaacuta
10 Vosssia cuspidate Acrostichum aureus Elaeis guineensis Mangifera indica 11 Raphia hookeri Laguncularia
racemose
Irvingia gabonensis Panicum maximum 12 Cocos nucifera Rhizophora mangle Terminalia
cattappa
Cynodon dactylus 13 Spondianthus preussii Symphonia
globulifera
Tectona grandis Cyperus digitatus, 14 Lemna sp Nypa fruticans Gmelina arborea Selaginella spp 15 Pandamus
candelabrum
Rhizophora mangle Sterculia tragacantha 16 Cyrtosperma
senegalensis
Ouratea spp Cola gigantean
17 Grewia coriacea Paulinia pinnata Mansonia altissima 18 Xylopia rubescens Chrysobalanus
orbicularis
Milicia excels 19 Lophira procera Vosssia cuspidate Klainedoxa
gabonensis 20 Sarcocephalus
nervosus
Ceiba pentandra
21 Nymphaea lotus Cynometra
megalophylla
22 Mitragyna ciliate Ricinodendron
heudelotii 23 Elaeis guineensis
24 Albizia adianthifolia 25 Hallea ledermannii 26 Oncocalamus spp
1 Sources: Keay 1989, Formecu (1999), Okafor et al (1994), NFAP (1995; Ezealor (2002) MCarthy et al (2010). Abere & Ekeke (2011) and Ebigwai et al 2014
Table 4.4.1.2: List of Fauna Resources found in Niger Delta Coastal Areas S/N Mangrove Forest Fresh water Swamp
forest
Lowland rainforest Modified habitat MAMMALS
1 Protexerus stranger
Manis tetradachyta (black bellied pangolin)
Syncerus caffer (African buffalo)
Xerus erythropus
2 Trichecus senegalensis
Manis longicondata (long tailed pangolin)
Pan troglodytes Protexerus strangeri
S/N Mangrove Forest Fresh water Swamp forest
Lowland rainforest Modified habitat 3 HYemoschus
aquaticus
Cercopithecus spp Cricetomys gambianus
Anthemrus africanus
4 Galago spp Anomalurus peli Genetta spp (genets) Erinaceus albiventris 5 Cercopithecus spp Protexerus stranger Eidolon helvum
(fruit bat)
Lemniscomys striatus
6 Loxodonta cyclotis Cercopithecus
nictitans (white nosed monkey)
Crocidure
Occidontalis nigeriae
7 Cephalophus niger
(black duiker)
8 Hybomys trivirgatus
(three-striped mouse)
9 Neotragus
pygmarreus (Royal antelope)
10 Syricapra grimmia
(Bushrel)
11 Loxodonta cyclotis
BIRDS Halycon
malimbicicus
Halycon senegalensis Stigmatopelia Senegalensis
Stigmatopelia Senegalensis Nettapus auritus Nettapus auristus Francohanus
Bicedcaratus
Francohanus Bicedcaratus Butroides striatus Anser spp Gallus gallus Tehitrea spp
Bubicus ibis Bubicus ibis Dendpicus fuscescens
Bycanisters fistulator
Milvus migrans Halietus vocifer Muscicapa strata Necrosyrtes monochus Circus
aeruginosus
Circus aeruginosus (marsh harrier)
Corvus albus
Pycononotus barbatus Malinibus rubricollis Hyphanturgus Prachypterus Bulbicus ibis
S/N Mangrove Forest Fresh water Swamp forest
Lowland rainforest Modified habitat Corytheala cristata
Reptiles
Agama agama Agama agama Dendroapsis viridis Dendroapsis viridis
Naja nivae Disphodus typus Naja nigricollis Hemidactylus
gasciatus Hemidactylus
gasciatus
Mabura blandingii Amphibians
Dicroglossus Occipentalis
Hyperlolius spp Bufo regularis Rama spp.
Xenopus tropicalis
Chiromantus spp Hyperlolius spp
Gigantorrim goliath
Xenopus tropicalis Rama spp.
Gigantorrim goliath
Sources: Moses (1985), SPDC (2004), Udoidiong & Ekwu (2011)
Characterization Method
To characterize the biodiversity resources, present at the study area, a combination of field surveys, laboratory examination and desktop assessments was used. Detailed biodiversity survey was conducted between 2nd and 22nd May, 2018 (Plate 4.4.1.1).
Plate 4.4.1.1: Biodiversity Sampling Activities