This study examined the ecological effects of local scale mangrove exploitation through surveys, empirical field experiments, modeling and questionnaires. The ecosystem “health” was assessed by parameterising a mass-balance model (ECOPATH with ECOSIM). The results suggest that forest exploitation affects mangrove forest structure and two-third of the canopy gaps were caused by human activities. Regeneration was affected, and more seedlings were recorded in canopy gaps compared to closed canopy areas. A total of 1358 crabs were collected to assess it population structure, 770 females (56.7%) and 588 males (43.3%), belonging to 13 species. The family Sesarmidae contains 5 species (38.5%), while Grapsidae 2 species (30.8%), Ocypodidae 1 species (15.4%) and to each of the families Portunidae and Gecarcinidae (7.7% each). Uca tangeri (Ocypodidae) and Goniopsis pelii (Grapsidae) were the two dominant species, constituting 44.1 and 21.9%, respectively, of the total sampled crabs. Propagules predation was a major source of mortality for mangrove. An average of 65.9% of the propagules was predated and most were found to be non-viable. The Ecopath analysis suggests that the Cameroon mangrove ecosystem is relatively healthy and moderately mature. This analysis allowed a reasonable model representation of the Cameroon mangrove system, as the model viability was determined by using the sensitive analysis function.
Part of the book: Mangrove Ecosystem Ecology and Function