| || || Nise, Olofa V. Tuaopepe.|
| || || Human impacts on coastal and nearshore ecosystems and biodiversity : case studies : Vailele, Gagaifolevao, Ma'asina and Ta'elefga villages of Upolu Island, Samoa |
Author:Nise, Olofa V. Tuaopepe.
Institution: University of the South Pacific.
Call No.: pac In Process
Copyright:20-40% of this thesis may be copied without the authors written permission
Abstract: The coastal and nearshore marine biodiversity provide fundamental resources for local communities of the Pacific Islands. The coast is the main area of settlement, agriculture and infra-structural development whilst the nearshore marine area is the main fishing ground of the Samoan, and other Pacific communities. Subsistence and artisanal fishing are significant in providing for the local people’s needs in substituting about half of their protein intake. Many activities along the coast and nearshore areas put pressure on resources such as coastal plants, sand and beaches as well as the inshore lagoon. Furthermore, the impacts of natural hazards like catastrophic cyclones exacerbate the destruction of these nearshore ecosystems and biodiversity. This research assesses and discusses human impacts on the coasts and nearshore biodiversity of Samoa focusing on the four villages of Vailele near Apia and the rural villages of Ma’asina and Ta’elefaga at Fagaloa on the northeast coast and Gagaifolevao at Lefaga on the southwest coast of the Island of Upolu. Main human impacts at these areas include infra-structural development, particularly the Afulilo Dam that feeds the hydro-electricity power station at Ta’elefaga, which has caused the decline, scarcity and local depletion of some nearshore marine species. As a result, sedimentation into the lagoon has increased thus causing the death of more than half of the coral cover; eradication of the sea hare (gau) and pen shell (fole); the rarity of the finfish purse eye scad (atule), the sea cucumber - pricklyfish (sea mao'i), venus clam (tugane) and the decline of the boring sea urchin (tuitui) and other species as explained in the results. In addition, high demand contributes to the over- harvesting of marine organisms resulting in the short supply of important species for consumption and sale, for example finfish, molluscs, echinoderms and crustaceans. Overfishing has led to the decline of particular species such as the unicornfish (ili'ilia) at Gagaifolevao and Vailele, the steephead parrotfish (galo) and the humphead maori wrasse (malatea/tagafa) at the four study sites. Destructive fishing methods were used such as the fish poison tree (futu) and the Derris malaccensis (ava niukini). The coral smashing (sasa'e) method of fishing caused the decline of the gregory finfish (tu'u'u) at Vailele and the breaking of corals is still used to fish for sea anemone (lumane, matalelei) at Gagaifolevao for selling in the village or at the market in town. Findings also from this research showed that cyclones were the main natural disasters that devastated the coastal and nearshore biodiversity of the study villages, particularly cyclones Ofa in 1990 and Val in 1991, which deposited Island rubble banks on the reefs of Vailele and Ma'asina. One of the main problems encountered during the research was identifying vernacular names of some marine and plant species. This limitation and lack of traditional knowledge was mainly with the young age groups interviewed. The severe impacts affecting the coastal and nearshore areas and the loss of traditional knowledge as found out by this research need to be addressed. The involvement of local communities in conserving their resources will bolster their participation and concern and thus develop their sense of responsibility in sustainable management of their nearshore ecosystems and biodiversity.