Title: Distribution of Queen conch (Strombus gigas) on the Pedro Bank, Jamaica: Descriptive and Predictive distribution models
Abstract
Species distribution models (SDM) are useful tools for describing and predicting species ecological role within its community or ecosystem. They are increasingly becoming important in the context of marine resource management and conservation in light of the the relative difficulty and expense of obtaining quality marine biological and environmental data. SDM have been applied to the marine realm in areas such as marine spatial planning (MSP), prioritizing for the establishment of protected areas, predicting and planning for the impact of non-native species and climate change mitigation. There is an on-going effort by private and public stakeholders to further develop and implement ecosystem based management approaches to Jamaicaʼs marine resources, in particular on socio-economically important species and habitats. In this context descriptive and predictive distribution models were developed for different size and age groups of the commercially important gastropod mollusc, Queen conch (Strombus gigas), on the Pedro Bank Jamaica. Species occurrence data from four abundance surveys (2002, 2007, 2011 and 2015) were modelled against the environmental variables; depth, substrate and primary production using generalized additive models (GAM) and Maxent. Descriptive results revealed that for both juveniles and adults there is a higher tendency toward shallower depths and substrates with relatively high amounts of their marcoalgal food. However, it is substrate complexity rather than specific substrate types that may be most important. Predictive models showed that not all supposedly suitable areas were being occupied by the species, but importantly also suggest priority areas for management of the species and its habitat in the context of the Pedro Banksʼ increasingly multi-use nature.