House Martins are easy to identify from above showing the distinctive the white rump © Colin Bates 
Their underside is white, with no breastband or dark throat. © lan Lewis
The Hampshire House Martin Project aims to raise awareness about House Martin declines, build our knowledge of nest sites and the size of the population in Hampshire – and provide artificial nest cups to boost breeding success.
In 2025 over 500 nest sites were reported by about 370 people across Hampshire, far more than we expected. We are now implementing a pilot scheme to fit free artificial nest cups in the north and east of the county. In 2026 we hope to discover new breeding sites and conduct a survey to find out how many pairs of House Martins nest in Hampshire.
The layers in this part-completed nest suggest that suitable mud was available only intermittently. © David Thelwell
An endangered species
Each April and May, House Martins return from Africa to spend the summer in the UK. They catch flying insects on the wing and build their cup-shaped mud nests under the roofs of houses and other buildings. Often, they form colonies with several nests in close proximity.
Hampshire Ornithological Society encourages the recording of all bird species in Hampshire. Some are doing well but the House Martin seems to be getting scarcer. Reflecting a wider decline, the House Martin has recently been added to the Red List of Britain’s most endangered birds.
With your help, we want to measure the scale of the problem and do something about it.
Collecting soft, sticky mud for a nest. © Edward Butler
What's the problem?
Where ponds and other insect-rich habitats have deteriorated or when the weather is poor, a lack of insects may make it difficult for them to find sufficient food.
Sometimes it is difficult for them to find soft mud from which to build their nests.
Their nests stick less easily to modern plastic soffits and may fall off, killing eggs and young and wasting weeks of time and nest-building effort.
This young House Martin (with white tips to its wing feathers) has fledged from an artificial nest cup. © Colin Bates
How are we helping?
In 2025 a team of HOS volunteers and many homeowners provided more detailed information on over 200 of the reported nest sites. These details will be analysed during the coming months.
We are now offering artificial nest cups, prioritising properties which would extend existing colonies, initially in a pilot area. This will save House Martins valuable time, make the nests more robust and should boost breeding success.
In 2026, we will again be pleased to receive reports of active nest sites from members of the public and hopefully fill some gaps in coverage. We also plan to survey a sample of about 300 1km squares for breeding House Martins. This will enable us to estimate the total Hampshire population and make comparisons with the national survey carried out in 2015.
You will find further information about House Martins and how you can help them on the website of House Martin Conservation UK & Ireland.
Questions about the Hampshire House Martin Project should be sent to