Fish preservation in marine fisheries
The small-scale fishery in the area has adopted a technique to preserve their fishes from deteriorating for two to three days by using improvised cold room constructed from plywood and stainless steel filled with iceblocks (Plate 4.6). This has prolonged the shelf life of their catches for two to three days.
Plate 4.6: Fishes preserved in an improvised cold room by fishers around the project area
The fishes in the area were said to have increased over the years compared to like 20 years ago in terms of number. This may be as a result of the length of nets used now and the distance the fishermen covered. Despite this, some species of fish have been identified as scare or not available. These are Lutjanus goorensis, guitar ray, ray fish, giant Tarpon atlanticus, sea tortoise, Pristis sp (sawfish) and Torpedo torpedo. The scarcity of these species may be as a result of the pressure on the fishes and increased number of fishermen.
Fish Migration
Migratory fish require different environments for the main phases of their life cycle which are reproduction, production of juveniles, growth and sexual maturation. The life cycle of diadromous species takes place partly in fresh water and partly in sea water: the reproduction of anadromous species takes place in freshwater, whereas catadromous species migrate to the sea for breeding purposes and back to freshwater for trophic purposes. The migration of potamodromous species, whose entire life cycle is completed within the inland waters of a river system. Fish migration is a phenomenon associated with reproduction, or food availability. Some of the exploited fish species, e.g., bonga, croakers, sardinella, snappers, threadfins, pink shrimp and barracuda, make seasonal migrations from the sea into the creeks and back to sea (OML 77
& 74 Baseline Study, 2018), mainly for reproduction. Such migrations are likely to influence movement of fishing units along the coast. The migration of these species can influence migration of fisher folks in the they may be more concentrated in a at a particular time of the
year than the other area which will affect the catches. Besides, the onshore/offshore and lateral migrations mean that several stocks are harvested by both artisanal and industrial fleets.
However, by the nature of the project, fish migration is not affected by the project because the diversity recorded has not been seriously affected. Although, fisher folks in the area noted that fishes in the area have drastically reduced due to interest and pollution that has rampage the area in recent times. In addition to these people also assumed that they are not secured fishing in the area due to security tension in the area this has limited fishing activities to the open waters where they can still be sure of safe operation.
Fish Breeding
Fish breeding in the entire area is very likely as varying sizes of fishes are caught by fishers in this area and the shore line is not in any way tampered or affected by the project. Adult fish that are ready for breeding are known to swim to shore areas or shallow parts of the river where they can lay their eggs and care for their young. These areas are also expected to be rich with enough micro food organisms for their young and fewer predators as well as disturbance. Such areas are mainly creeks and rivulets.
4.8: Marine Biodiversity
Aquatic biodiversity contributes a wide range of ecosystem services. However, they are the most vulnerable to pollution because of anthropogenic activities and infrastructure development that are further challenged by climate change impacts. The proposed project is one of the mega off shore oil developmental projects in the area in recent times, which is planned for geophysical data acquisition in 2019. This report provides a baseline assessment of mammalian, avian and reptilian taxa survey for the project. Fishery report is covered elsewhere in the report. However, results of the scoping workshop conducted on November 2019 in Akassa revealed predicted impacts on marine lives, making baseline study of aquatic biodiversity imperative.
Results presented for each species include species sighted/indirectly censored, species abundance, coordinates where sighted, depth where sighted, behavioural activity when sighted, time/tidal regime when sighted, species indigenous uses, and the analysed water physicochemical parameters at the sighted depth. The result for the sighted turtle species also included delineation and conditions of nesting sites and nesting sites oil physicochemical parameters. Parameters reviewed for each species are IUCN status, national protected status and reserve location, breeding seasons, feeding patterns, type of predator threats, migrant/non-migrant classification and raptors (avian fauna only). The report on each species also presented interviews with the locals and Akassa Development Foundation (ADF) on the local names of directly/indirectly censored species, regularity of species/egg catch/sighting and species poaching/consumption. Also, soil samples for physico chemical analyses were collected on established and potential turtle nesting sites.
Three mammalian, two reptilian and 23 avifauna species were sighted during this study. On the other hand, two mammalian and three reptilian Taxon were censored via indirect evidences.
4.8.1: Reptilia Species Study
The species sighted were Chelonia mydas (Green turtle) and Dermochelys coriacea (Leatherback sea turtle) both in the order Testudines. On the other hand, Crocodylus niloticus (Nile crocodile) Caretta caretta (Loggerhead sea turtle) were censored via various indirect evidences and are in the reptilian orders Croccodylia (Crocodylus niloticus) and Testudines (Lepidochelys olivacea and Caretta caretta).
4.8.1.1 Chelonia mydas (Green Turtle) Species Frequency of Chelonia mydas
This species was sighted in four locations (4.337895/5.982486; 4.341395/ 5.944029;
4.297461/6.021926 and 4.288614/6.055960). These sites are located about 45.3m, 47m, 80m and 30m nautical miles from Sangana, Fishtown, Okumbiri and Okumbiribeleu communities respectively. Figure 4.15 is a geo-reference map of the location sites of this species.
Figure 4.15: Locations of sighted Chelonia mydas