The Life Cycle, Use and Exploitation of Ostrea edulis (Native Oyster)

This blog sets out to summarise the life-cycle, exploitation and use of Ostrea edulis using resources researched for a literature review of the same title.

Ostrea edulis (also known as the Native Oyster) is a protandrous alternating hermaphrodite. This means that they start life as a male and produce sperm, after which they change sex to female and produce eggs. The change happens according to a temperature trigger and they change sex at least twice during their spawning season which occurs between April and September. This is why Native oysters are not harvested between these months. The eggs are fertilized when the externally released sperm are filtered through the oysters across the eggs which are stored in the mantle cavity. Once fertilized the eggs spend 8-10 days in incubation before being released as swimming larva. The larva produced spend around 8-10 days swimming around in what is known as a pelagic phase, before settling on a surface, attaching themselves with a form of concrete and maturing into the Oyster we visually recognize.

Fig. 1 Native oyster. MarLIN website


Ostrea edulis is currently in decline and outlined in the UK. Biodiversity action plan. Many reasons for its decline have been noted. The Whitstable oyster company website notes that “commercial pollution, disease and bad winters” are responsible for the decline. The UK Biodiversity Action plan website explains that a historical increase in demand due to improvement in rail transportation has lead to over exploitation of the Oyster. Further evidence of the popularization of the Oyster can be found in Lewis Carroll’s book "Through the looking Glass" which, written in 1871, contains an entire poem dedicated to the consumption of oysters.

The use of Ostrea edulis has primarily been as a food source. The BBC food website gives notes that Oysters can be eaten raw but also provides links to recipes which include the oyster. The Falmouth Bay Oyster company, who produce both the Native Oyster and Pacific Oyster, provides information as to how to open and store your oysters.

Other uses of Ostrea edulis have been noted historically and in the modern day. One example of this is the use of native oyster shells as a building material. Callendar House in Falkirk, which was built in the 14th Century, has lime mortar made from oyster shells dug out from neolithic shell middens.

A more recent example of Oyster shells being used as a building material is the Pavilion in St. Albans, designed by muf architecture art. The building was created to house a roman mosaic found beneath the park in St. Albans and uses oyster shell aggregate, originally a Roman martial, on the outside of the building. The Oyster shells (around 60, 000 of them) were sourced from County Waterford in Ireland, where both the Native Oyster and the Pacific Oyster are grown; therefore we can not distinguish which species was used.

Fig. 2 St. Albans Pavillion. (muf website)


Useful websites for the Native Oyster.

MarLIN website gives a comprehensive overview of the Native Oyster.

Fisheries and Aquaculture website gives general information on Native oyster as well as the commercial production of the oyster.


UK Biodiversity Action Plan website gives information as to the status of oyster and current action plans for the protection of the oyster.