Wren of Britain and Ireland

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The Wren, Troglodytes troglodytes, is a small, lively bird who lives and breeds in shrubs, hedges and trees. They are the most common and numerous breeding bird in Britain and Ireland as they have adapted to living in nearly every habitat. Most people in Britain and Ireland are very fond of Wrens because of their tiny size and shy nature.

The Wren population has remained stable in recent years because of the mild winter weather. Sadly, the so-called “Beast from the East” in 2018 caused a significant drop in their numbers.

Other names for the Wren include the “British Wren”, “Jenny Wren”, “winter wren” (North America), Northern Wren and Eurasian Wren.

Wrens are busy little birds who spend their lives on their territories throughout the year. They have adapted to living in a wide variety of natural and man-made environments. Most prefer to remain hidden among the lower twigs and branches of shrubs, hedges and trees.

Woods and forests provide Wrens with thick vegetation where they can forage for food and make their nests. They are also found in hedgerows, farmland, scrubland, moors, heathland, sea cliffs, mountains, off-shore islands, parks and gardens. 

City centres and areas with extensive low vegetation such as grassy lawns are normally avoided.

Large numbers of Wrens die during the cold weather in winter, particularly when there are prolonged times of snow and ice. Their tiny size and a scarcity of insects during the cold winter weather can lead the loss of up to 80% of the population. Wrens soon recover as they produce large broods of chicks.

“Research published by the British Trust for Ornithology shows northern populations of the tiny songbird are more resilient in winter as they endure 70 per more frost days than are faced by their southern counterparts” (Express).

Gardens are particularly valuable foraging areas for wrens during the winter. “They can be aided in harsh weather with mealworms, finely broken breadcrumbs, oatmeal and grated cheese, but supplements should be scattered near low cover, as wrens don’t readily attend bird tables” (Countryfile).

The British Trust for Ornithology advised gardeners keep a compost heap and turn it over regularly so the insects inside may be easily found by wrens and other birds.

The Wren is classified as of Least Concern by IUCN.

The global population is not considered Vulnerable by conservationist groups because of the wide range of these birds (Eurasia).

Europe accounts for 5% to 24% of the global range. The Wren population in Europe was reported as increasing between 1980 and 2013 (Birdlife International).

The BTO said in 2009 that “The Wren’s current UK population estimate is the highest for any species”. The population can crash during prolonged winter weather as, for example, in the 1960s.

“Following a rapid recovery up to the mid 1970s, abundance fell again in response to a further series of cold winters, only to return to its previous high level”.

There were “minor decreases” in southern England between 1994 and 2009 although “strong increases” occurred in North Wales, northern England and mainland Scotland.

The charity also said there has been “widespread moderate increase across Europe since 1980” ( BTO - Trends).

The Wren is a green-listed species of bird in Britain.

The Breeding Bird Survey stated the population of Wrens:

• - declined by 5% between 1995 and 2011 ( RSPB)
• - declined by 4% between 2012/13 (BBS - page 17)
• - increased by 34% between 2013/14 (BBS - page 13)
• - declined by 1% between 2014/15 ( BBS - page 13)
• - increased by 9% between 2015/16 ( BBS - page 15)
• - increased by 1% between 2015/17 ( BBS - page 15)
• - declined by 21% between 2017/18 ( BBS - page 15)

The BTO said in 2018 that the “spell of fierce winter weather nicknamed the ‘Beast from the East’ in late February and early March 2018 hit some of the UK’s smallest resident bird species hard. Goldcrest declined by 38%…and Wren by 21% between 2017 and 2018” (BBS - page 14).

The WBBS report stated in 2018 that the top five most widespread species along waterways were “Wren which were recorded on 95% of stretches, Chaffinch and Woodpigeon on 94%, and Blackbird and Mallard on 93% of stretches” (BBS - same link above - page 32).

According to the State of the Birds in the UK 2017, “Resident species such as great tits, wrens and nuthatches appear to be benefitting from milder winters…trends for great tits and wrens show that increases have been greatest in Northern Ireland, followed by Scotland, with no significant difference between England and Wales”.

“These patterns are likely to be caused by overall population increases and improving climatic conditions in the north and west ( State of the Birds in the UK - page 14).

The RSPB said Wrens also enjoyed a slight range expansion in Scotland because of the mild winter weather in recent years (RSPB Handbook of Scottish Birds).

The Wren is also a green-listed species of bird in the Republic of Ireland.

A survey by Birdwatch in Ireland reported the population as stable and had increased between 1998 and 2010 (Countryside Bird Survey - page 6).

Wrens are susceptible to hypothermia during prolonged cold weather in winter, as in 2012 to 2013 (Guardian).