How geographic distance and depth drive ecological variability and isolation of demersal fish communities in an archipelago system (Cape Verde, Eastern Atlantic Ocean)

Cape Verde is a tropical oceanic ecosystem, highly fragmented and dispersed, with islands physically isolated by distance and depth. To understand how isolation affects the ecological variability in this archipelago, we conducted a research project on the community structure of the 18 commercially most important demersal fishes. An index of ecological distance based on species relative dominance (Di) is developed from Catch Per Unit Effort, derived from an extensive database of artisanal fisheries. Two ecological measures of distance between islands are calculated: at the species level, DDi, and at the community level, DD (sum of DDi). A physical isolation factor (Idb) combining distance (d) and bathymetry (b) is proposed. Covariance analysis shows that isolation factor is positively correlated with both DDi and DD, suggesting that Idb can be considered as an ecological isolation factor. The effect of Idb varies with season and species. This effect is stronger in summer (May to November), than in winter (December to April), which appears to be more unstable. Species react differently to Idb, independently of season. A principal component analysis on the monthly (DDi) for the 12 islands and the 18 species, complemented by an agglomerative hierarchical clustering, shows a geographic pattern of island organization, according to Idb. Results indicate that the ecological structure of demersal fish communities of Cape Verde archipelago, both in time and space, can be explained by a geographic isolation factor. The analytical approach used here is promising and could be tested in other archipelago systems.

Improving How Listening Skills are Taught in the Efl Classroom: Guidelines to Producing Better Speakers of the English Language

This research paper is concerned with the need to improve how listening skills are taught in the Capeverdian EFL classroom. Teaching English through listening is not an easy task, especially when there are many factors that impede the learning process such as: lack of adequate materials and conditions; lack of qualified teachers with good pronunciation, and lack of innovative approaches to teaching listening skills. If our goal as teachers is to produce good English speakers we must invest in training good listeners. In this work I will focus on the following aspects: an evaluation of how effectively listening skills are taught in the Capeverdian EFL classroom; a look at how we can turn teaching problems into positive solutions; how to improve teaching listening skills and materials and recommendations for best practices in teaching listening skills in the EFL classroom. In conclusion I will include listening activities which reflect these best practices and offer recommendations for further research.