Abstract

Jamaica has over 30 springs. There is a lack of information on tropical springs. Springs that discharge water above the mean annual air temperature (MAAT), which is 24.91°C in Jamaica, are referred to as thermal springs. There are two types of thermal springs- warm and hot springs. Warm springs’ temperatures range from 1-2°C higher than the MAAT up to 37°C. Hot springs have a temperature higher than 37°C. In this study both warm and hot springs have been investigated. Fish species have only been identified in the warm springs. Based upon monthly samples collected over a period of 14 months the following fish families and species were observed: Eleotridae - Gobiomorus dormitor (n=2), Poecilidae - Limia melanogaster (n=38), Gambusia wrayi (n=75) and Xiphophorus maculatus (n=5), Cichlidae - Parachromis managuensis (n=105), Mugilidae - Agonostomus monticola (n=20) and Gobiidae - Awaous banana (n=12) Of the species captured at the warm spring, X. maculatus and P. managuensis are Jamaican introduced species, making up 43% of the entire fish population. P. managuensis was the most abundant fish species and they constituted 95% of the introduced species population. Gut-content analyses provided data on the feeding habits of the species. P. managuensis, G. wrayi and G. dormitor mainly fed on invertebrates. X. maculatus and L. melanogaster mainly fed on diatoms while A. monticola and A. banana mainly fed on filamentous algae. Pianka’s Index was used to identify the percentage overlap for the invertebrates recorded during the gut analyses. This was highest between P. managuensis and A. monticola (76%). Therefore, they might be in competition for food. This is currently being investigated.

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