The Farne Islands, Northumberland--Famous for its puffins, the Farne Islands retain their popularity among those who love seabirds. The islands are also home to terns and guillemots, and the nearby Lindisfarne Nature Reserve boasts geese and godwits. Naturetrek, Wanderlust and BirdSpot all recommend the spot, and suggest visiting sometime between April and July.
Exe Estuary, Devon--The River Exe Estuary contains two Royal Society for the Protection of Birds (RSPB) bird reserves, Exminster and Powderham Marshes and Bowling Green and Goosemoor Marsh. The Estuary is famous for its wading birds, such as avocets and wigeons--which is only too appropriate, given that the avocet is the symbol of the RSPB! BirdSpot places it 3rd on their list and HolidayCottages recommends the site as well, and both recommend visiting between November and February--although I imagine that such a beautiful site is worth seeing in the spring as well, especially given the better weather!
Minsmere Nature Reserve, Suffolk--Another highly-recommended birding site (cited by HolidayCottages, Wanderlust and BirdSpot, which recommend visiting from May-June) is RSPB's Minsmere reserve. Minsmere is home to bitterns, nightingales and even plenty of other animals, such as Polish Konik horses and highland cattle. The reserve is split into four zones and covers 1000 acres.
If you plan to go birdwatching this spring, make sure to wear a mask--despite being out in the open, these sites can be quite busy during peak bird season and it's important to be considerate to other visitors.
Feature Image Credit: Wikimedia.com