Marine environmental conditions in the SW Indian Ocean and sympathetic trends of coastal fish catch

Abstract

This study considers marine environmental factors driving fluctuations in coastal
fish catch in the SW Indian Ocean using FAO data. A consistent oscillation of catch is found for Mauritius, Madagascar, Reunion and the Comoros, and is shown to be related to a widespread change in marine environmental conditions that prevails during the preceding year that include the following:
- An upper ridge of high pressure is present to the south of Madagascar where SSTs are above normal;
- Southerly winds are stronger to the east of Madagascar; westerly winds are strengthened in the monsoon zone around 5- 10 S;
- Dry weather prevails in a NW-SE band across Madagascar and the adjacent island nations;
and,
- Sea surface temperatures (SST) off Angola increase well in advance.
Further work is needed to compare marine environmental signals that could emerge from locally sourced fish catch data and those reported here with the FAO time series.

Keywords: Indian Ocean, climate change, fisheries

West Indian Ocean Journal of Marine Science Vol. 4 (2) 2005: pp. 199-206