Mumini Dzoga, Cosmas Munga, Judith Okello, Ali Shee, Kevin Tole, Mariam Swaleh

Abstract

Mangroves are critical ecosystems that support the riparian coastal communities and marine aquatic life. They provide habitat and breeding areas for fisheries. In addition, they are known to be the primary sources of protein and food among the coastal community. These ecological services of mangroves are at risk of getting diminished through sustained deterioration as observed in Mtwapa Creek. We used Geographical Information System (GIS) method to generate spatial data for 2003, 2013, and 2023 to describe cover change of the mangrove forest. Also, we conducted mangrove forest structure survey to establish the current status of the forest. Mangrove coverage from 2003 to 2023 showed a degradation at a rate of 12.04%. Mangrove utilization was high for fito (5651.36 ± 1509.53) followed by pau (778.27 ± 572.32), boriti (254.81 ± 212.60), mazio (99.01 ± 70.66) and nguzo (58.27 ± 24.61). Across all zones, the quality of trees in Mtwapa mangrove forest is densely populated by form 2 and 3 and dominated by the species Rhizophora mucronanta (Kruskal Wallis test: p < 0.005). In terms of forest utilization, there was no significant difference in tree quality across all species and zones (Kruskal Wallis test: p ˃ 0.005 both cases). Cutting pressure was high at the mid-creek, followed by upper-creek and lower-creek, respectively. Regeneration Class II and III was high compared to Regeneration Class I. Thus Mtwapa mangrove forest is characterized by non-selective cutting in terms of tree quality and dominated by non-mature tree with low quality forest which produced fewer propagules for Regeneration Class I regeneration. Management intervention is required to protect this forest in order to sustain ecological functions.