A House Martin’s journey.
Recently, I’ve been watching a House Martin pair build a nest under the eaves of a building near the Severn
estuary. A member of the Hirundinidae family, House Martin are small birds, with glossy, blue-back upper parts,
tiny black beaks and white under parts. They are about 5 inches/12 cms with less pronounced V-shaped tails than
Swallow and weigh just over half an ounce/19g. These little birds make an amazing journey from sub-Saharan
Africa in April/early May each year to grace our shores for our brief summer. Their scientific name, Delichon
urbicum comes from the Greek : khelidon = the swallow and Latin : urbis = a city.
Feeding on insects caught in flight in their gaping beaks, House Martin nest in colonies, returning year after year to
the same location. Originally nesting on cliffs, they now take to nesting on manmade structures such as houses,
bridges and barns. Nest building begins within a few days of their reappearance in this country from Africa.
Worryingly, the population of these tiny birds has declined by 18% in the past 10 years. During 2013, the British
Trust for Ornithology (BTO) received several reports of long-established colonies being abandoned, possibly due to
the cool, wet summer. The House Martin is now amber listed as a species of conservation concern.
I’ve watched the local pair building their nest with fascination - it can take up to two weeks and 1,000 beakfuls of
mud to build each nest! Within days of completion, the mud home dried out, and the pair then collected feathers
and fine grasses to line the interior. House Martin nests are closed, save for an entrance hole once they are
complete……..and are beautiful works of avian art.
The House Martin hen then laid her eggs and she and the male began incubating them until the young hatched
c14-16 days later. The bald, pink-skinned chicks needed brooding as the weather veered unpredictably between
windy, wet, cold and damp. But all seemed to be going well as the parent birds frantically whizzed back and forth
bringing food to the nest, a high-protein diet of flies, beetles and aphids. Then we had a series of very hot, dry
days and disaster struck……the nest dried out and collapsed. It was a heart breaking sight.
The resilience of nature never ceases to amaze me and as I write this, the plucky pair have rebuilt the nest and it
seems that another clutch of eggs has been laid……
(Photo credits – Steve Hale)
The British Trust for Ornithology (BTO) are hoping to solve one of ornithology’s great mysteries: where do House
Martins go for the winter? Once this tiny bird crosses the Sahara, it disappears. In a bid to answer this mystery, the
BTO have fitted shirt-button sized geolocators to House Martin in the UK that will reveal their winter location. For
more information and to support BTO work, go to http://www.bto.org/support-us/appeals/house-martin-appeal
Please help monitoring House Martin…………let ALWG know if you see any. Thanks!