The Sussex Wildlife Trust (SWT) is a conservation charity which aims to protect natural life in Sussex. It was founded in 1961 and is one of 46 wildlife trusts across the UK and the Isle of Man and Alderney. As of 2019, it has 33,000 members and manages 2,000 hectares of land for nature. It is a registered charity and in the year to 31 March 2019 it had an income of £5.7 million and expenditure of £4 million, resulting in net income of £1.7 million.
Ardingly Reservoir is west of Ardingly in West Sussex. The southern end is a 74.5-hectare (184-acre) Local Nature Reserve owned and managed by South East Water.
Weir Wood Reservoir is a 153.5-hectare (379-acre) biological Site of Special Scientific Interest west of Forest Row in East Sussex. It is in High Weald Area of Outstanding Natural Beauty and an area of 32.6 hectares is a Local Nature Reserve which is owned by Southern Water and managed by East Sussex County Council and Southern Water.
Wild Park is a 239.8-hectare (593-acre) Local Nature Reserve adjacent to Lewes Road in Brighton, East Sussex. It is owned and managed by Brighton and Hove City Council. It includes Hollingbury Castle, an Iron Age hillfort which is a Scheduled Monument, and Hollingbury Park golf course.
Ham Street Woods is a 175.2-hectare (433-acre) biological Site of Special Scientific Interest south of Ashford in Kent. It is a Nature Conservation Review site, Grade I, and an area of 97.1 hectares is a National Nature Reserve.
Tilgate Forest is a 6.9-hectare (17-acre) Local Nature Reserve in Crawley in West Sussex. It is owned and managed by Crawley Borough Council and is part of Tilgate Park.
Ebernoe Common is a 233.9-hectare (578-acre) biological Site of Special Scientific Interest in Ebernoe, north of Petworth in West Sussex. It is a Nature Conservation Review site, Grade I, a national nature reserve and a Special Area of Conservation. It is managed by the Sussex Wildlife Trust
Crowborough Country Park is a 7.3-hectare (18-acre) Local Nature Reserve on the western outskirts of Crowborough in East Sussex. It is owned and managed by Crowborough Town Council.
The Scrase Valley is an 8-hectare (20-acre) Local Nature Reserve on the eastern outskirts of Haywards Heath in West Sussex. It is owned and managed by Mid Sussex District Council.
Tottington Wood is a 5.1-hectare (13-acre) Local Nature Reserve in Small Dole in West Sussex. It is owned by Hopegar Properties and managed by The Tottington Woodlanders.
Slinfold Stream and Quarry is a 2.3-hectare (5.7-acre) geological Site of Special Scientific Interest west of Horsham in West Sussex. It is a Geological Conservation Review site.
Burton Park SSSI is a 57.7-hectare (143-acre) biological Site of Special Scientific Interest west of Pulborough in West Sussex. A larger area of 63 hectares, including Chingford Pond to the west, is designated a Local Nature Reserve called Burton and Chingford Ponds, which is managed by the Sussex Wildlife Trust and West Sussex County Council. The site is adjacent to Burton Park, a Grade I listed building.
Climping Beach is a 32.1-hectare (79-acre) biological Site of Special Scientific Interest west of Littlehampton in West Sussex. The eastern half is designated a Local Nature Reserve called West Beach.
Grattons Park is a 7.7-hectare (19-acre) Local Nature Reserve in Crawley in West Sussex, England. It is owned by Crawley Borough Council and managed by the council and Gatwick Greenspace Partnership.
Target Hill Park is a 9-hectare (22-acre) Local Nature Reserve in Crawley in West Sussex. It is owned by Crawley Borough Council and managed by the council and Gatwick Greenspace Partnership.
The Mens is a 205.2-hectare (507-acre) biological Site of Special Scientific Interest west of Billingshurst in West Sussex. It is a Nature Conservation Review site, Grade I and a Special Area of Conservation. An area of 166 hectares south of the A272 road is managed as a nature reserve by the Sussex Wildlife Trust.
Wakehurst and Chiddingly Woods is a 155.9-hectare (385-acre) biological and geological Site of Special Scientific Interest south-east of Crawley in West Sussex, England. It is a Nature Conservation Review site, Grade I, and part of it is a Geological Conservation Review site.
Lynchmere Commons is a 122-hectare (300-acre) Local Nature Reserve in Lynchmere in West Sussex. It is owned and managed by the Lynchmere Society.
Warnham LNR is a 38.4-hectare (95-acre) Local Nature Reserve in Horsham in West Sussex. It is owned and managed by Horsham District Council.
