Granddad’s Camera
Bittern, as it appears in the game

No.040 · Birds · Very rare

Bittern

Botaurus stellaris

A secretive, streaky brown heron whose deep foghorn boom carries for kilometres over the reeds. Hearing one is easy in spring; seeing one is a real event.

When to look

May to August, mostly at dawn, day and dusk.

Time of day

Best time
Dawn and dusk. Males boom from late winter to early summer, best from late March to June; in hard winters birds move to open water edges.
Where in the game
the Norfolk Broads (reedbed, broad and fen)
Size
Length 70–80 cm (Wildlife Trusts)
Wingspan
About 1.3 m (Wildlife Trusts)
Weight
About 1.2 kg (BTO)
Lifespan
Oldest ringed bird 11 years 11 months (BTO); most live far shorter lives
Population
283 booming males in Britain in the 2024 survey, a record (RSPB); just 11 in 1997
Status
Amber (Birds of Conservation Concern 5, 2021)

Diet

Eels, small fish and amphibians, hunted by freezing or stalking slowly through reed edges

Habitat

Large wet reedbeds with shallow water and plenty of fish

Breeding

Males boom to attract several females. Clutch 4–6 eggs, incubated by the female for 25–26 days; young fledge at about 50–55 days.

Field signs

  • A deep, far-carrying 'boom' at dawn and dusk, like blowing across a bottle
  • Vertical stripes and a stabbing bill; when alarmed it points its bill up and sways like reeds
  • Large greenish feet leaving marks in mud at reed edges

Did you know?

  • Bitterns fell to just 11 booming males in Britain in 1997; reedbed creation and restoration has raised that to 283 in 2024 (RSPB).
  • Only male bitterns boom, and the sound carries up to three miles, making it the UK's loudest bird (RSPB).
  • The 2024 count was a 20% rise on the previous survey, the biggest jump since monitoring began in 1990 (RSPB).

Moments worth waiting for

  • Bittern booming March to June, dawn and dusk
    From deep in the reeds comes a low, throbbing boom, three or four times in a row.
  • Bittern feeding flight June to July, dawn, day and dusk
    A bittern rises above the reeds on broad, owl-like wings with a fish for hungry young.

Photo tip

Go to a hide overlooking reedbed edges at dawn in spring and wait for a flight over the reeds or a head poking out. Use a 500 mm lens and high ISO for low light; do not wait on a footpath in the open.

Be a good naturalist

Bitterns are Schedule 1 birds, so stay on paths, stay in hides, never use playback of the boom, and leave when a nest site is near. Never walk into reed to get a better angle.

The law

Schedule 1 of the Wildlife and Countryside Act 1981: it is an offence to intentionally or recklessly disturb one at or near the nest, or the young.

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