Dr Fiona Gell, marine biodiversity officer with the Department of Environment, Food and Agriculture, looks back on an inspiring workshop
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The third horse mussel researcher’s meeting was held in Port Erin.
It was well attended with around 20 scientists, divers and students presenting work and discussing the complex requirements of monitoring, protecting and managing these bivalve molluscs.
The horse mussel (Modiolus modiolus) is particularly important, because its complex byssal thread structures hold the sediment and each other together to form potentially large biogenic reef structures which, in turn, support significant biodiversity.
Their loss, or damage to them, often due to mobile fishing gear activity, can have major influences on the seabed and the number and type of organisms found there.
Ironically it may also have detrimental effects on fisheries themselves, as the reefs provide food and shelter for many commercial species.
However, we are becoming more aware of their value, and efforts to protect them, often involving the fishing industry itself, are increasing.
The group heard of several successes and failures in their conservation, notably in Strangford Lough in Northern Ireland, west Wales and in Scotland.
The species is predominantly a temperate/cool water bivalve, and its potential as a climate change monitor was a major topic of conversation.
The main Isle of Man horse mussel site, off the Point of Ayre, and protected as part of the Ramsey Marine Nature Reserve, was also discussed as it has been monitored since its discovery in the late 1990s.
As part of the workshop, survey dives were planned at this site and also at a new mussel reef off the island.
Dives were conducted on the Thursday afternoon and Friday morning, providing the group from Herriot Watt University in Edinburgh, Natural Resources Wales (formerly CCW) and local divers with an opportunity to observe and monitor the reefs close up.
The weather was perfect for diving and all agreed that the sites were exceptional, particularly the new one.
Samples were taken as part of the monitoring programme and are currently being quantified for species diversity.
The Isle of Man appears to have some locally, and potentially internationally, significant horse mussel reef areas, and so further research and conservation work seems likely to be directed towards them in years to come.
