Site of Special Scientific Interest

A Site of Special Scientific Interest (SSSI) in Great Britain, or an Area of Special Scientific Interest (ASSI) in the Isle of Man and Northern Ireland, is a conservation designation denoting a protected area in the United Kingdom and Isle of Man.

Sites of particular significance for various taxonomic groups may be selected (for example birds, dragonflies, butterflies, reptiles, amphibians, etc.

Exposure sites are where quarries, disused railway cuttings, cliffs or outcrops give access to extensive geological features, such as particular rock layers.

Deposit sites are features which are limited in extent or physically delicate—for example, they include small lenses of sediment, mine tailings, caves and other landforms.

Following devolution, legal arrangements for SSSIs (Scotland, England, Wales) and ASSIs (Northern Ireland) differ between the countries of the UK.

An SSSI may be made on any area of land which is considered to be of special interest by virtue of its fauna, flora, geological or physiographical / geomorphological features.

When designating an SSSI/ASSI, the relevant nature conservation body must formally notify the interested parties and allow a period for them to make representations before confirming the notification.

Under the current legal arrangements they are called 'operations requiring consent' or ORCs (Scotland), or 'operations likely to damage the SSSI interest' or OLDs (England & Wales).

The intention of this was to remove the need for owners and occupiers to obtain SSSI consent as well as licences/ permits from other authorities (who must consult NatureScot prior to determining such applications).

If a proposed activity would not affect the interest or is beneficial to it, then the conservation body will issue a "consent" allowing it to be carried out without further consultation.

Conditions may cover any relevant aspect of the proposed operation and may, for example, limit its timing, location or intensity.

The process is slightly different where the owner or occupier is a public body, but the effect is broadly similar.

Where an owner or occupier is unwilling or unable to carry out management, ultimately the conservation body can require it to be done.

Site management statements for SSSI in Scotland are available to download from the NatureScot website using the "Sitelink" facility.

This meant that damaging activities such as fly-tipping, intensive bait-digging or trail biking on an SSSI were only prevented if done (or permitted) by the owner or occupier – not if done by trespassers or under public rights.

Funding for the monitoring of SSSIs in England has been cut from £1.58 million in 2010 to £700,000 in 2018, causing concern that many have not been inspected over the last six years, as required by guidelines.

Since the referendum to leave the EU in 2016, more than 450 staff have been transferred to the Department for Environment, Food and Rural Affairs (Defra).

Arlington Reservoir , a 99.4-hectare (246-acre) biological SSSI in Arlington, East Sussex
Long Mynd , view up Ashes Hollow towards Pole Bank