Conservation physiology of marine and freshwater crabs

One of the biggest challenges facing our planet today is the maintenance of food security for a growing population. We urgently need to identify new sources of protein for production that are both ecologically and socially-economically sustainable, and that are also resilient to climate change and disease. Integrating knowledge of the physiological diversity and ecophysiology of novel aquatic species is allowing us to assess their response to projected global change processes and their suitability for use in sustainable aquaculture settings.

Dr Lucy Turner is leading work in India to explore the potential of crabs as novel aquaculture species. Her work is integrative, using a combination of whole animal physiology, biochemistry and molecular biology approaches.

Together with PhD student Elina Apine, she is exploring the potential of the mud crab (Scylla serrata) to be used as a sustainable small scale aquaculture species in India, particularly on the west coast where there has been lower take up of this fishery. Their work includes multi-trophic level mesocosm experiments to follow both the physical (e.g. freshening and warming) and biological (e.g. associated increases in toxin producing phytoplankton and harmful bacteria) effects of projected climate change on the ecophysiology of mud crabs, as well as next generation sequencing techniques to explore the effects of disease on the gut microbiome.

The data generated is particularly important to assess the resilience of these crabs under global change scenarios, especially when placed in the context of the investment made by farmers. To explore social-economic perspectives of these issues further they are also collaborating with Dr Lynda Rodwell

Lucy Turner is also working with Dr Christopher Thorpe, Professor John Spicer and Professor Mairi Knight on the freshwater crab Barytelphusa cunicularis which is widely distributed throughout India’s vast riverine network, to assess its potential as a sustainable commodity species. Working along a 1,700 km latitudinal gradient, and from 50-600m elevation in south-west India they are using molecular ecology techniques to describe the population size and structure of this species to confirm its conservation status. These data are complemented by whole animal physiology approaches which are being used to quantify the species’ physiological diversity and to assess its physiological suitability and viable latitudinal and altitudinal range for aquaculture.

The mud crab Scylla serrata prepared for export from India
The mud crab Scylla serrata prepared for export from India
Collecting water quality parameters at a freshwater crab sample site in south west India
Collecting water quality parameters at a freshwater crab sample site in south west India

Selected publications

Turner, L.M., Havenhand, J.N., Alsterberg, C., Turner, A.D., Girisha, S.K., Rai, A., Venugopal, M.N., Karunasagar, I. & Godhe, A. (2019) Toxic algae silence physiological responses to multiple climate drivers in a tropical marine food chain. Frontiers in Physiology, 10, 373. doi.org/10.3389/fphys.2019.00373

Apine, E., Turner, L.M., Rodwell, L.D. & Bhatta, R. (2019) The application of the sustainable livelihood approach to small scale-fisheries: The case of mud crab Scylla serrata in South west India. Ocean and Coastal Management, 170, 17-28. doi.org/10.1016/j.ocecoaman.2018.12.024

Turner, A.D., Dhanji-Rapkova, M., Rowland-Pilgrim, S., Turner, L.M., Rai, A., Venugopal, M.N., Karunasagar, I. & Godhe, A. (2017) Assessing the presence of marine toxins in bivalve molluscs from Mangalore, southwest India. Toxicon, 140, 147-156. 10.1016/j.toxicon.2017.11.001

Turner, L.M., Alsterberg, C., Turner, A.D., Girisha, S.K., Rai, A., Havenhand, J.N., Venugopal, M.N., Karunasagar, I. & Godhe, A. (2016) Pathogenic marine microbes influence the effects of climate change on a commercially important tropical bivalve. Scientific Reports, 6, 32413. doi.org/10.1038/srep32413