Tree sparrows are a farmland bird species, typical of lowland arable and mixed farming areas. Sadly, they have undergone one of the largest declines of any farmland bird species - a 95% decrease in population between 1970 and 1998 (BTO). Smaller than the more familiar house sparrow, they can be identified by their wholly chestnut coloured forehead, crown and nape and distinctive black cheek spot. The sexes are alike.
Their scientific name, Passer montanus, is derived from the Latin Passer meaning a sparrow and montanus meaning a mountaineer - a somewhat puzzling name considering the species habitat preferences here in the UK. However, the tree sparrow has a vast world distribution and in some areas they can be found on much higher ground, sometimes well over 2000 feet above sea level.
Tree sparrows here in the UK need a good supply of seed food in the winter and as adults in the breeding season, whereas a plentiful supply of insects is required to feed chicks. They nest in holes and will readily take to nest boxes, positioned close together, as they are semi-colonial breeders.
Here at Langford, the tree sparrow has always been a species we are keen to see do well on site and one that has an interesting history. They bred on site for the first time in 2010, with just one pair fledging four chicks. This gave us high hopes for the future, but the following year provided no breeding records, despite good numbers being present at our feeding station throughout the winter. 2012 then saw them return as a breeding species, with 2 pairs fledging 24 young. Again, hopes were raised, but as in 2011, the following year saw no breeding records on site.
Provisions in place for the birds here include around 40 nestboxes in the Phase 1 scrub and winter feeding, viewable from the viewing screen on the public footpath. We feed a mix of seed with a high proportion of red millet - a favourite seed of tree sparrows.
Since the 2012 breeding season, we have only had a handful of tree sparrow records and none at all since April 2013. We are always keeping an eye and an ear open for these charming little birds and would be very interested to hear from anyone who has seen or heard them anywhere on site. So, please do get in touch via the contents section on this blog, send us a Forum post, or phone the office on 01363 893611 with any sightings!
Tree sparrows. Andy Hay (rspb-images.com)