Rossmore Oyster Farm, Cork, Ireland.
Opportunity to join our small team – apply below.
Exciting Job Opportunity – Positions available.
We have an exciting opportunity for a research student who would like to help breed native oysters this summer. The main job would be to sample the 22 breeding ponds, and watch the larvae grow, and then catch the young oysters on shells! Full training will be given onsite, and much of the day will involve sampling ponds and measuring larvae with a microscope, and then watching them grow, from roughly 0.2mm to 5mm. Other jobs may include fishing parent oysters, and also nurturing our small oysters in our nursery system on shore, laying of young seed oysters on trestles, caring for young oysters and turning bags. The job is roughly from June to August 2022. Please do send your CV to Rupert by email, by clicking here.
We are also looking for part time people, who would like work more shore based for grading and packing work. This could be flexible hours, with mornings being more suitable. If you would like to be involved, please do contact us for more information.
The Rossmore oyster farm is based near Cork, in southern Ireland, located in an unique eco-system that has been a natural home for oysters since the Neolithic times, as seen in the huge middens of oyster shells found around the shores.
Our farm covers 10 hectares on land, including our large packing shed and has seven depuration tanks. We have 22 man-made ponds for breeding, and 13Km of trestles in the sea, for nurturing young oysters.
We are authorised by the Sea Fisheries Protection Agency, and have full traceability and testing data for every month we harvest the oysters.
Rock Oysters
Our rock oysters are grown in the traditional way. Young oyster spat (or seed) arrive at Rossmore at around 2mm in size; at this point, half a million oysters fit easily into a few polystyrene boxes! These little oysters are carefully placed into our nursery system, where they are immersed into nutrient-rich sea water. The oysters grow happily and quickly to around 8mm in size, when they are graded, to make sure only the largest are harvested for going out into the open sea. These 8mm oysters are placed into a mesh bag, where they will grow for the first year of their life.
These mesh bags are placed on to our trestles, located out in the sea, and we turn the bags every month to stop them growing onto each other and the bags. After a year, the oysters are big enough – and their shells are strong enough – to withstand the onset of crabs. The young oysters are then spread out on to the seabed, where they grow for a further two years. Whilst on the seabed, the shell develops into a deep cupped shaped, and the oysters grow a very full meat.
After about three years, once the oysters are fully grown, our boat, the Haematopus, is put to work, dredging the oysters on a regular basis, bringing back our oysters ready for purification and sorting before market. Oysters that are grown on the bottom of the sea are of the very finest quality, and this is what makes our Rossmore oysters so special. We hope you agree.
Native Oysters
We have been breeding Rossmore Native oysters since 1970, and every year we select the healthiest, plumpest oysters to breed from for the future generations, ensuring our much-loved oysters continue year after year. The science of breeding oysters is exciting. In a good year, each mother oyster can produce a million larvae; in a bad year, maybe none. We are continually refining and adding to our knowledge of oyster breeding, but after 50 years, are fairly confident we know what we’re doing. We have 22 ponds, which each contain one million litres of water, pumped in directly from the sea in the summer as the water starts to warm. The parent oysters are then placed into the ponds to breed and the warmer environment encourages them to spawn.
The tiny larvae are nurtured in the pond for 10 days, growing to 1/2mm in size before they look for somewhere to settle. We place old, cleaned, mussel shells in the ponds and the baby oysters (or spat) gradually settle onto these shells. (This also gives Rossmore oysters a unique identification tool: if the bottom of your oyster has a small piece of mussel shell attached, it may well be ours). The spat then grow in the ponds until they are about the size of a fingernail, when they are considered strong enough to be scattered into the open sea, onto our well-prepared beds. They stay here for the next three years, until they are ready to be harvested.
Purification
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