Joanne Preston, course leader of Marine Biology at the University recently appeared on BBC TV show, Coast, a show that explores the natural and social history of the coastline around the UK. Joanne spoke about the decline in Native oysters around the Solent and the research being carried out to improve their survival.
Until recently the Solent had one of the largest remaining O. edulis fisheries in Europe. Since 2007 there has been a dramatic population crash, thought to be due to multiple pressures including over-exploitation, decreased water quality, disease and competition from invasive species. It is evident that native oysters within the Solent are struggling to recover. Without conservation efforts to protect adult broodstocks and habitats, it is feared this species could become absent from the area in the near future. Over the last year, staff and researchers at the Institute of Marine Sciences have been using the Langstone Harbour research raft to trial a novel aquaculture method for protecting the threatened native oyster Ostrea edulis.
Our research is part of an ambitious collaboration with Blue Marine Foundation to restore the Solent oyster population, and the associated biodiversity and ecosystem benefits this species brings to our coastal environment. During 2015/16, Luke Helmer, a MSc Applied Aquatic Biology student carried out a pilot study aims to trial off-bottom, suspended oyster cages as a suitable aquaculture method to house mature O. edulis that are protected from predators, fishing and habitat destruction.
The trial was a success, and revealed that this floating aquaculture method can provide a protected environment for the protection, growth and reproduction of the native oyster Ostrea edulis in the Solent region. The ultimate aim of this study is to maximise the potential of this aquaculture method as a source of larvae to contribute to the repopulation of the native seabed populations across the Solent. However, we also found that water quality and algal blooms may have a significant detrimental impact on survivorship.
We are now rolling out the next ambitious phase to deploy this aquaculture method across the whole of the Solent. With the help of Marine Biology undergraduates, we are currently putting 9000 native oysters into specially designed microreef structures in time for Christmas which will be monitored during 2017. Watch this space! #bringbackthenative #UoPMarinebiol
Light Microscopy photographs of the pallial fluid of Ostrea edulis containing numerous veliger 'D' Larvae. The adult oyster was taken from LRBAR pontoon cages in the Camber dock, Portsmouth Harbour and fixed on the 27th July 2016. Photo © Luke Helmer