It is a marshy nature reserve run by the Royal Society for the Protection of Birds (RSPB) and is known for its population of pied avocets and terns.

[2] Havergate Island comprises six salt water lagoons covering 60 hectares, surrounded by earthen banks.

[3] There are also areas of grazing marsh and mud flats, and the site provides important habitat for rare gulls, wading birds and other species.

Butterfly species commonly found on the island include skippers, small coppers, walls, meadow browns and gatekeepers.

Active habitat management of the lagoons is employed to benefit the islands breeding and wintering bird populations.

Long-term plans however accept that the island is likely to be lost and will be allowed to change into salt marsh as part of the strategy of managed retreat.

In the 1930s it was used for summer grazing and in 1933 a gravel company set up shingle extraction on the island but this was found to be unprofitable and they soon left.

Without human intervention during this time salt water flooded parts of the island making it unsuitable for agricultural use.

[19][20] In 1947 pied avocets were found on the island, as well as at nearby Minsmere, for the first time in the UK since they had become extinct in the country over 100 years before.