The house sparrow recently came in at top place in the UK big garden bird watch and there are thought to be more than 5million pairs in the country, so it might come as a surprise that these noisy, gregarious little birds are less than half as common as they were in the late 1970s. House sparrows are slightly larger than robins with a wingspan of 21 to 25 centimetres and grow to weigh around 31 grams. Both the males and females have mottled brown wings but the males have distinctive head markings that helps to separate them. This includes white cheek patches, a grey cap, chestnut markings down the back of the head and a black bib. This bib varies in size depending on the birds social status. Young birds look very similar to females but have a more washed out appearance and have slightly yellow looking beaks.
As their name suggests, house sparrows have long been associated with people with records of them living alongside us as early as 11000 years ago in the middle east. Since then they have spread with people across most of Europe, northern Africa and Asia and over the last 200 years they have also colonized much of the American continents and Australia. This relationship with people has been supported by two main factors. Firstly they have managed to find lots of suitable nesting sites around our houses and other structures, often nesting beneath loose roof tiles and in the eaves of buildings and secondly because of their ability to digest the starchy foods that we produce in agriculture such as potatoes, corn and wheat. These foods make up a portion of their diet but they will also eat a wide range of other foods including seeds, berries and fruits and also insects throughout the spring and summer.
When it comes to nesting, house sparrows prefer to do it communally and will often nest very close to other pairs. When this isn’t under tiles and in eaves, they will also use man made nest boxes, holes in trees and amongst dense bushes and ivy. Each female will lay between 3 and 5 mottled cream and brown eggs. Both parents share the incubating duties and the eggs take between 11 and 14 days to hatch. They will start incubating before all the eggs are laid and this means that as the chicks develop, some will be smaller than others. If there isn’t enough food whilst the chicks are being reared this will give the larger and stronger ones more chance to outcompete their siblings and successfully fledge. Once hatched, the chicks take from 14 to 16 days to fledge the nest. The parents then feed them for a further two weeks before they are fully independent.
In the UK house sparrows do not migrate but they sometimes disperse away from their breeding areas throughout the winter to find food on farmland and woodlands. As mentioned before, house sparrows have suffered a severe decline since the 1970s which has been attributed to changes in farming practices and modern houses providing less suitable nesting sites. This decline seems to be levelling out in some places with some populations in Scotland and northern Ireland increasing over the past few years. The house sparrows average lifespan is just 3 years but in Texas in 2004 a bird was found that had been ringed more than 15 years before!

Massive thanks to Tom Cross and Gen Fiske White for allowing me to use their house sparrow egg photographs. Toms original picture can be found here: https://tinyurl.com/h3nk7e8p and Gens Instagram is here:
  / genny2shoes  

Some of the footage in the video was obtained using creative commons licences, the originals and their licence information can be found at:
   • Txolarreak, hormatxoriak, artatxoriak...  
   • Sparrow Feeding Fledgling  

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