The males make a distinctive ‘booming’ call to attract a mate — once heard, never forgotten!  Somerset Wildlife Trust’s Westhay Moor NNR is a great place to catch up with this enigmatic bird.

The bittern, a type of heron, is a secretive species of tall, marshy habitats, especially reedbeds. Its cryptic, straw-coloured plumage can make it seem almost invisible to onlookers, which is why you should consider yourself very lucky if you manage to spot one!

Bitterns became extinct in the UK at the turn of the 20th century through habitat loss, and after making a recovery in the 1950s, they were nearly lost again locally in the 1990s, due to deep drainage for peat extraction. A second extinction was averted through concerted conservation work to create new reedbed habitats from these worked-out peat areas, especially in the Avalon Marshes. This area now boasts one of the biggest populations of bitterns in the UK, with regular sightings at Ham Wall (RSPB), Shapwick Heath (Natural England) and Westhay Moor (Somerset Wildlife Trust).

Although they can be notoriously difficult to see, in spring, dozens of enthusiastic volunteers head out to these reserves very early in the morning to listen and count our booming bitterns. By analysing the booms and grunts these birds make, it is actually possible to identify individuals! Over the last decade, numbers have been on the increase, and we regularly count between 40 and 50 males across all Somerset Levels’ sites.

If these males are lucky enough to find a mate, that is the end of their part in the breeding process, as the females take over and look after the nests and young. In a few weeks, our hardy volunteers will return and sit for many hours in high seats looking over the reedbeds.  This allows us to estimate how many nests there are by studying the regular feeding flights of the females. While this is not an exact science, it gives a good indication of the population without disturbing these elusive, unique creatures, which have made a very welcome return to the Avalon Marshes.