Interim profile, incomplete information
General Impact
Nypa fruticans displaces native mangrove vegetation throughout the Niger Delta and in Cameroon (Saenger and Bellan 1995) and forms dense monospecific stands that outcompete native species. Particularly in areas where native red and white mangroves (Rhizophora sp.) are felled for fuel wood and sale, the resulting exposed mudflats are readily colonised by the opportunistic N. fruticans. In such areas where nypa palm is dominant there is often low incidence of encrusting tree fauna and little or no evidence of burrowing crabs due to the dense stand structure of the palm (Sunderland and Morakinyo 2002; Isebor et al. 2003). Its dense structure also chokes mangrove vegetation in which fish breed, and thus may contribute to the decline of fish populations in the area (Sunderland and Morakinyo 2002).
Areas that are invaded by nypa palm are more at risk of erosion, leading to destabilisation of foreshores and increased water turbidity. The lack of stilt roots (pneumtophores) in N. fruticans may also affect sedimentation processes. Shrimp larvae, molluscs and other estuarine species may be affected by these effects (Isebor et al. 2003).
Unlike native mangroves, nypa palm does not produce leaf litter. As leaf litter important as primary production in estuarine food webs, invasion by N. fruticans may affect microbes and fauna that utilise it (Isebor et al. 2003).
Floating masses of nypa palm can destroy nets and cages set by fisherman, thus potentially having economic impacts. The displacement of native mangrove species also deprives fisherman of fuelwood for smoke-drying fish and constructing huts. The economically important Crassostrea gasar is also less common in areas where nypa has established. This gastropod is an important source of protein and an economically renewable resource for coastal dwellers (Isebor et al. 2003).
Location Specific Impacts:Niger Delta (Nigeria) 
Competition: Nypa fruticans displaces native mangrove vegetation throughout the Niger Delta and in Cameroon (Saenger and Bellan 1995) and forms dense monospecific stands that outcompete native species. Particularly in areas where native red and white mangroves (Rhizophora sp.) are felled for fuel wood and sale, the resulting exposed mudflats are readily colonised by the opportunistic N. fruticans.
Economic/Livelihoods: Floating masses of nypa palm can destroy nets and cages set by fisherman, thus potentially having economic impacts. The displacement of native mangrove species also deprives fisherman of fuelwood for smoke-drying fish and constructing huts. The economically important Crassostrea gasar is also less common in areas where nypa has established. This gastropod is an important source of protein and an economically renewable resource for coastal dwellers (Isebor et al. 2003).
Ecosystem change: Areas that are invaded by nypa palm are more at risk of erosion, leading to destabilisation of foreshores and increased water turbidity. The lack of stilt roots (pneumtophores) in N. fruticans may also affect sedimentation processes. Shrimp larvae, molluscs and other estuarine species may be affected by these effects. Unlike native mangroves, nypa palm does not produce leaf litter. As leaf litter important as primary production in estuarine food webs, invasion by N. fruticans may affect microbes and fauna that utilise it (Isebor et al. 2003).
Reduction in native biodiversity: In areas where nypa palm is dominant there is often low incidence of encrusting tree fauna and little or no evidence of burrowing crabs due to the dense stand structure of the palm (Sunderland and Morakinyo 2002; Isebor et al. 2003). Its dense structure also chokes mangrove vegetation in which fish breed, and thus may contribute to the decline of fish populations in the area (Sunderland and Morakinyo 2002).
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