A photograph taken from the bank of the Dornoch Firth with far-reaching veiws across the calm water. The sky is blue with white clouds and across the water you can see the coastline where the Glenmorangie Distillery Company is based.

DEEP Project oyster reintroduction

We’re a proud founding partner of the Dornoch Environmental Enhancement Project, reintroducing European flat oysters to the Dornoch Firth.

DEEP is an innovative and award-winning environmental project supporting the reintroduction of European flat oysters to the Dornoch Firth after a century’s absence.

Native oysters flourished in the Firth up to 10,000 years ago before being wiped-out in the 19th century due to overfishing. Their return to the Firth for the first time in over 100 years will enrich the ecosystem of an important marine habitat.

European flat oysters provide a wealth of ecosystem services. Not only do they enhance biodiversity and create nursery habitats, they also improve water quality by filtering up to 200 litres of water a day and contribute to the stabilisation of carbon in the marine environment.

Volunteers and staff members from the DEEP project (Dornoch Environmental Enhancement Project) scatter native oysters from a boat.

Head of Policy and Advocacy Calum Duncan and the DEEP team deploying oysters into the Dornoch Firth  |  Image credit: The Glenmorangie Company

About the project

DEEP was formed in 2014 by The Glenmorangie Company with the Marine Conservation Society and Heriot-Watt University.

The shared vision is to restore long-lost oyster reefs to the Dornoch Firth, a Special Area of Conservation, enhancing biodiversity and acting in tandem with a new anaerobic digestion plant. The plant purifies the by-products created through The Glenmorangie Company's distillation process – an environmental first for a Distillery.

A successful re-introduction of native oysters to the Dornoch Firth as part of a ‘survivability’ trial in 2017 coincided with Glenmorangie officially opening the €6million plant at its renowned Tain Distillery.

The plant is expected to purify up to 98% of the waste water that the Distillery releases into the Firth with the remaining 2% of the organic waste accounted for by the filter feeding of the oysters.

We're proud to deliver community and staff engagement, communications support and advocacy for DEEP, and look forward to supporting the project toward a goal of some four million native oysters covering around 40 hectares. Progress has been made with 100,000 of this target already being met.

Project update - November 2026

For the first time in more than 100 years, native oysters have successfully reproduced in the Dornoch Firth.  

Scientists from Heriot-Watt University discovered young oysters, known as spat, during routine monitoring of the restoration site. Their identification was independently verified by experts at National Museums Scotland and Amgueddfa Cymru – Museum Wales, with some subsequently growing to the size of a 50p piece.

This is a major milestone for the DEEP project and an important sign that the restored oyster population is beginning to reproduce naturally.

A close up of a girl wearing a hi-vis jacket dropping a handful of native oysters from a boat.

Aisyah Wan, DEEP intern and Professor Bill Sanderson adding oysters to the Dornoch Firth  |  Image credit: Gurjameer Ramday

Since the project began, more than 140,000 juvenile oysters have been bred and released into the Firth, with a further 5,000 recently added. The project partners will continue monitoring the developing population, working towards the long-term goal of restoring four million native oysters across 40 hectares of the Firth by 2031.

Sandy Luk, our CEO said, “We are so excited that oysters in the Dornoch Firth have successfully reproduced. This historic milestone shows what is possible and will help inform our oyster regeneration projects across the UK.

“The breeding success wouldn’t have been possible without the help of hundreds of volunteers who supported the DEEP scientists. Their dedication has been vital to restoring these long-lost oyster beds, which not only provide habitat for other species but also help capture carbon and improve water quality.”

Sandy Luk, CEO

Project update - November 2024

We were delighted to help The Glenmorangie Company and Heriot-Watt University reach a huge milestone of 100,000 native oysters to the Dornoch Firth, as part of the DEEP project. The Glenmorangie Company, Heriot-Watt University and the Marine Conservation Society have worked together for 10 years to reach this achievement.

To ensure DEEP can expand its future capacity, Glenmorangie has also commissioned a new workboat, ‘Dornoch Dancer’, built by local company Leco Marine based in nearby Alness. It will allow greater numbers of oysters to be transported to reef sites and provide a bigger working platform for DEEP’s divers.

Professor Bill Sanderson, Lead scientist, Heriot-Watt University showing oyster growth by holding up European oysters from a boat. He is wearing a dry suit.

Professor Bill Sanderson, Heriot-Watt University  |  Image credit: JP Photography

Over the past 10 years, we’ve proudly shared the project’s story with locals and visitors. We’ve also recruited volunteers to help clean oysters, playing a key role in the project's visionary goal of creating habitat for more species, locking up carbon and improving water quality.

Calum Duncan, Head of Policy and Advocacy

Oysters in numbers

30

years

Native oysters can live up to

200

Litres filtered each day by each oyster

85

%

Global decline in native oysters

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