Quantification of climate change implications for water-based management: A case study of oyster suitability sites occurrence model along the Kenya coast

Abstract

To ensure long-term sustainability of the littoral marine ecosystem for water-based management and aquaculture potential, it is necessary to quantify and project the effect of sea warming on the resident biota. This study evaluated the potential of an oyster Suitability Sites Occurrence Model (SSOM) to predict the status of littoral areas in the future due to sea warming. Data sources comprised Moderate Resolution Imaging Spectroradiometer (MODIS) and Landsat 7 ETM+. The suitable sites were ranked on a scale of 1 (least suitable) to 5 (most suitable). In the suitability model, score 5 had the highest proportion (35.8%) of oyster suitability which shrank to 16.2% with a 4°C increase in sea temperature. Future increases in sea temperature are likely to cause shrinkage in the spatial extent of most suitable and suitable oyster sites. Thus changes in marine oyster suitability in littoral zones are predicted to worsen gradually as sea temperatures increase in the future. Differences in the recorded sea temperature of ≤6°C within and between sites may influence spatial variations in oyster habitat due to future sea warming. Such concepts could form an alternative scientific basis for quantification of potential global climate change effects on biodiversity for marine systems policy adaptation analysis, aquaculture potential, and management.