Gambia Bird Watching – Marine & Coastal Birds
Multiple bird species and good birding can be found in the many different marine and coastal habitats on Jinack Island in The Gambia. As well as bird watching, the geographical diversity and un-spoilt beauty of the Island provides special opportunities for the study and research of other wildlife, flora and fauna.
Permanent Shallow Marine Waters
Between Barra Point and Buniada Point the coastal profile is a gently shelving sand embayment with a predominantly northerly current. The depth of water at high tide is in the region of 5 meters up to 2km offshore. There is considerable movement of sediments in the vicinity of Buniada Point where sand bars extend up to 2km to the west.
Much of this sand deposition is the result of erosion further south along the shoreline of Jinack Island. Anecdotal information suggests that the beach in front of Madiyana Camp has been eroded more than 15m in the past years.
There appears to be little sub-tidal vegetation though the occasional presence of eel grass Cymodocea nodosa along the shoreline which suggests there may be beds within the confines of the park (Ramsar Study, 1996).
The northern tip of Jinack Island forms a estuary for the outflow of a number of bolongs, some of which derive from the Delta du Saloum. The Masarinko bolong is the main water body within the Niumi National Park and rises as two streams of 1km inland.
The freshwater flow on these bolongs is negligible during the dry season and they are brackish to saline through out the year. The habitats associated with these water bodies includes mangrove forest, inter tidal mudflats and salt marsh. In their upper reaches freshwater pools persist into the dry season but ultimately dry completely.
Rice is cultivated on the upper flood plains of the rivers under the canopy of relict gallery forest.
A single coastal lagoon occurs at Buniadu Point on the north Shore of Jinack Island occupying an area of ca 2ha. The lagoon is maintained by the accumulation of sediments arising from the outflow of the Mansarinko Bolon and the northerly currents from the mouth of the Rive Gambia. The sediments form a spit which runs north – west from Buniada point for a distance of ca 1km. the lagoon is periodically inundated by the sea on spring tide through a channel on the north east side, though in recent months tidal surges have pushed over the westerly bank and there is a possibility this will ultimately form a breach. The seaward fringe of the lagoon is vegetated with a pioneer community of Ipomea pes-caprae, Sesuvium portulacastrum, Cenchrus biflorus and Cyprus spp. Occasional Avicennia shrubs occur on the southern edge which grades into Dichrostachys thicket with emergent A. digitata.
Niumi National Park has two main creek systems running through it. The Niji bolon connects to the ocean immediately north of Barra point and to the Mansarinko Bolon at the Senegalese border thereby forming the island of Jinack. This bolong is subject to the regular diurnal tidal cycle and as it has a small catchment area there is relatively little seasonal variation in salinity.
The Mansarinko bolong divides north of Mbamkam to form the Ker Jatta and Duniajoes bolongs. These bolons have a combined catchment in the region of 100km square and 33 resultantly have a marked seasonal variation in salinity. During the dry season hyper – saline conditions exist in the upper reaches due to limited tidal flushing and high evaporation rates.
As the rains commence dilution occurs and the salinity levels reduces progressively. The associated vegetation with these bolongs is predominantly mangrove where there is a gentle gradient on the banks.
Elsewhere, the vegetation ranges from woodland to grassland. There appears to be no associated aquatic vegetation within the bolongs with the exception of the mangrove complex.
The upper reaches of Ker Jatta and Duniajoe bolongs have seasonal freshwater flow. There are a number of other small bolongs both on the island of Jinack and on the mainlands which are rains fed but due to small catchment areas are more prone to rapid salinisation through a combination of evaporation and intrusion.
The Ker Jatta and Duniajoe bolongs have an associated floating / emergent freshwater vegetation dominated by Nymphaea lotus and N. micrantha, (atypha) and Cyperus spp, with Marsilea sp, Ageratum sp, Urena lobata and various graminae. The areas have relic gallery forest fringing the bolongs which in some areas has been cleared underneath for rice cultivation and seasonal vegetable gardening.
The freshwater stretches of these bolongs currently lies outside of the proposed park boundary though their inclusion is due to be negotiated with the neighboring communities in the near future for the proposed Niumi Biosphere Reserve initiative.
Gambia Bird Watching Holidays, Trips & Tours
Follow the link for a brief outline of the birding and bird watching opportunities available during the year – African Bird Watchers Calendar