A Long-Term Assessment of Habitat Fragmentation in Coastal Wetlands, Niger Delta, Nigeria
The landscape of the Niger Delta is under threat because of rapid population increase and a thriving oil industry. This threat has necessitated many studies in the area to investigate the rapid changes occurring in different part of the Niger Delta. However, there has been limited focus on the changes taking place in the coastal areas of the Niger Delta. This study examined the pattern of landscape fragmentation in the coastal wetlands of the Niger Delta using remote sensing data of 1987, 2002 and 2017. The data were classified into five dominant landuse classes viz settlement, forest, mangrove, cultivation and water. The assessment of habitat fragmentation was carried out using FRAGSTAT v.4.2 to determine the level of habitat fragmentation in the area. The results showed that freshwater forest increased by more than 28% while mangrove forest and cultivation lost 5% and approximately 20% respectively. Landscape metrics showed an increasing mean patch size (3.37 ha in 1987, 6.48 ha in 2017), reducing number of patches (1340663 in 1987, 683926 in 2017), and patch density (7.68 in 1987, 3.92 in 2017), suggesting landscape homogenization in the area between 1987 and 2017. Therefore, although current conservation efforts may be succeeding, the fragile nature of the Niger Delta wetlands calls for sustainable utilization of the available resources in the wetlands. The pattern of change observed in this study provides a basis for the development of ecological conservation strategies for planning, monitoring and management of these resources.