The Bittern, once believed to have become extinct in the UK due to habitat loss, has been making a slow comeback. This one was spotted on the Penrose Estate.
Photo: Richard Birchett

BITTERN

Scientific name: Botaurus stellaris

Other common names: Eurasian Bittern; some local names include Mire Drum, Butter Bump and Boom Bird

Conservation status: IUCN Red List, Least Concern; UK Birds of Conservation Concern, Amber; protected under Schedule 1 of the Wildlife and Countryside Act 1981

What to look for:

• Family: Herons, storks and ibises
• Colouring and appearance: Brown and buff with streaky markings. A long heron-like bill and brown-green legs.
• Size: 69 to 81 cm length, 100 to 130 cm wingspan.
• Where: Reedbeds and water edges
• Call: Listen to the famous booming call of the male

You need sharp eyesight, patience and a fair measure of luck to spot a Bittern. Even if, in spring, you hear the male’s famous booming call, pinpointing the bird itself is a tall order, given its excellent camouflage. With its brown and streaky plumage and silent stalking, it vanishes into the shadows of its reedbed home, as it uses its strong, heron-like bill to probe for prey. If disturbed, a Bittern will freeze, its beak pointing upwards, and completely blend with its surroundings: this distinctive behaviour is known as bitterning.

Once feared to be extinct in the UK due to habitat loss as wetlands and reedbeds were drained, the Bittern has been making a slow comeback since the start of the twentieth century. After originally returning to the east coast, it can now also be found in Wales and the west country following reedbed habitat restoration. There are now almost 200 males UK-wide in the breeding season, and almost 800 overwintering birds (source: BTO, 2017 figures).

Males will mate with up to five females (polygamy). The booming call made to attract and find females is produced by the expelling of air from its oesophagus. Each mated female raises one brood in a year, usually of four to six eggs, laid in a nest among the reeds, which she incubates for almost a month. After hatching, the young fledge in a little under two months.

Bitterns feed on fish, small mammals, amphibians and insects.

Did you know…?

… There are slight differences in the booming call between individual males. These are probably indistinguishable to less expert ears, but bird scientists can use these differences to identify one bird from another.

Published: March 2021
Author: Amanda Scott
Photo: Richard Birchett (website and YouTube channel)

Find out about other bird species you can see on the Lizard