Publications by authors named "S E Venables"

Opportunistic in-water and aerial surveys in South Africa and the analysis of contributed citizen science data have extended the known range of reef manta rays Mobula alfredi along the eastern coast of Africa by 140 km (to Mdumbi Beach) and verified the first transboundary movements for the species. Additionally, six new long-range dispersal records have provided evidence of connectivity with the M. alfredi population off the Inhambane coastline of Mozambique.

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In shallow water, downwelling light is refracted from surface waves onto the substrate creating bands of light that fluctuate in both time and space, known as caustics. This dynamic illumination can be a visual hindrance for animals in shallow underwater environments. Animals in such habitats may have evolved to use polarization vision for discriminating objects while ignoring the variations in illumination caused by caustics.

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The largest known reef manta ray (Mobula alfredi) population in Africa has been monitored for more than 20 years at several locations on the coast of the Inhambane Province in southern Mozambique. Nonetheless, before this study, little had been reported on the population dynamics of M. alfredi from Závora, a remote bay in the region.

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Little is known about the extent of genetic connectivity along continuous coastlines in manta rays, or whether site visitation is influenced by relatedness. Such information is pertinent to defining population boundaries and understanding localized dispersal patterns and behaviour. Here, we use 3057 genome-wide single-nucleotide polymorphisms (SNPs) to evaluate population genetic structure and assess the levels of relatedness at aggregation sites of reef manta rays (Mobula alfredi) in southern Mozambique (n = 114).

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Issues Addressed: To determine cardiovascular health benefits in Indigenous men following short-duration small-sided games.

Methods: Fourteen sedentary Indigenous males (35.6 SD 7.

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