The following birds have been recorded in Firle since April 2005.
- Barn Owl
- Blackbird
- Blackcap
- Black Redstart
- Black-headed Gull
- Blue Tit
- Brambling
- Brent Goose (c150 flew SW, Oct 2005, c40 flew SW Oct 2011)
- Bullfinch
- Canada Goose
- Carrion Crow
- Chaffinch
- Chiffchaff
- Coal Tit
- Collared Dove
- Common Buzzard
- Common Crossbill
- Common Gull
- Common Sandpiper
- Common Snipe
- Coot
- Cormorant
- Corn Bunting
- Cuckoo
- Dunnock
- Egyptian Goose
- Feral Pigeon
- Fieldfare
- Firecrest (March 2007, March 2010, August 2010, Oct-Dec 2011)
- Fulmar (July 2009)
- Gadwall (Jan 2012)
- Garden Warbler
- Glaucous Gull (March 2007)
- Goldcrest
- Golden Plover (Nov 11)
- Goldfinch
- Grasshopper Warbler (Sept 2006)
- Great Black-Backed Gull
- Great Spotted Woodpecker
- Great Tit
- Green Sandpiper
- Green Woodpecker
- Greenfinch
- Grey Heron
- Grey Wagtail
- Greylag Goose
- Hen Harrier
- Herring Gull
- Hobby
- Honey Buzzard (June 2009, PCS)
- House Martin
- House Sparrow
- Jackdaw
- Jack Snipe (1 in Jan 2010)
- Jay
- Kestrel
- Kingfisher
- Lapwing
- Lesser black-backed Gull
- Lesser Redpoll
- Lesser Whitethroat
- Linnet
- Little Egret
- Little Owl
- Long-tailed Tit
- Magpie
- Mallard
- Marsh Harrier (Aug 2010)
- Marsh Tit (Aug 05, Sept & Oct 09)
- Meadow Pipit
- Mediterranean Gull (Mar 12)
- Merlin
- Mistle Thrush
- Moorhen
- Nightingale (May 2005)
- Nuthatch
- Osprey (1 April 2010)
- Peregrine
- Pheasant
- Pied Flycatcher (Aug 05)
- Pied Wagtail
- Raven
- Redshank
- Red Kite
- Red-legged Partridge
- Redstart
- Redwing
- Reed Bunting
- Reed Warbler
- Ring Ouzel (Oct 11)
- Robin
- Rook
- Sand Martin
- Sedge Warbler
- Siskin
- Skylark
- Song Thrush
- Sparrowhawk
- Spotted Flycatcher
- Starling
- Stock Dove
- Stonechat
- Swallow
- Swift
- Tawny Owl
- Teal
- Tree Pipit
- Treecreeper
- Tufted Duck
- Turtle Dove
- Waxwing (Dec 2008)
- Wheatear
- Whinchat
- Whimbrel
- Whitethroat
- White Stork (2, August 2008, seen in all three parishes)
- Wigeon (Dec 2010)
- Willow Warbler
- Woodcock
- Woodpigeon
- Wren
- Yellow Wagtail
- Yellowhammer
Total: 124 species
