Department of Biological and Medical Sciences

The Adaptive Genomic Response and Impact of Illegal Shark Fishing on Prey Species

  • (Applying a landscape genomic approach to determine the adaptive genomic response and impact of illegal shark fishing on prey species in the Lutjanidae family) 

    In common with all species, marine species have declined dramatically, by 36% in the last 40 years (LPI Index 2016).  Sharks are no exception, as they are subject to over-exploitation in terms of illegal and over-fishing. The output from this research will provide a better understanding of the downstream effects of illegal shark fishing in the UK British Indian Oceans Territory (BIOT), in the Chagos Islands.  This region represents the world’s largest no-take Marine Protected Area and as such represents a unique opportunity to study species in one of the world’s healthiest reef ecosystems.  Specifically, we are interested in investigating the effects of declining shark populations on population structure and gene expression of competitor and prey species.  Working with samples collected from the sharks’ prey – fish from the Lutjanidae family, we are using the genomic techniques of RAD-seq and RNA-seq to investigate the population genetics and gene expression in these prey populations.  The morphology of prey species in areas of high and low shark predation is markedly different, with species in areas with low predation exhibiting much larger body dimensions and slower behavioural responses.  We are interested in understanding the genetic basis for these differences, and will use the genomic analyses to help determine whether illegal shark fishing is influencing adaptive processes in prey species.

    Photo 6 - Blue shark cropped

    Blue Shark– one of the Chagos species threatened by overfishing globally (Image MarkConlin/NMFS – Public Domain)