The Tree Sparrow is one of our rarest birds associated with lowland and mixed farmland, having undergone declines of 90% between 1970-2012*. It was a source of great excitement therefore when 24 birds were photographed feeding at a supplementary feeding table on RSPB’s Hope Farm in November 2014. The photo was taken by remote camera as part of a UEA MSc project by Holly Neville-Smith testing the effectiveness of different remote camera units for photographing farmland birds. The location of the feeding table within 5m of a sown wild bird mix was chosen to maximize the number of birds that would potentially visit the table, and shows the importance of winter seed food in attracting and supporting granivorous birds. At their peak it is estimated that up to 25 Tree Sparrows were present on the farm overall, since then the birds have dispersed, with small numbers present into February 2015.
Image 1: 24 Tree Sparrows seen feeding on a ground feeding table near to a sown wild bird mix on Hope Farm, November 2014
The image above highlights one of the ‘Big 3’ requirements of the Tree Sparrow, abundant seed food throughout the winter. These winter seed sources have declined in lowland and mixed farmland areas, mainly due to declines in over-wintered stubbles, use of broad-spectrum herbicides and more efficient harvesting techniques. Management at Hope Farm has sought to attract winter seed-eating birds by providing sown areas of wild bird mix. This supplies a reliable seed source for most of the winter and thus provides crucial support for species such as Tree Sparrow and Yellowhammer during the leanest months. The sown bird mixes typically contain millet, quinoa, barley, triticale and fodder radish, an energy-rich mix essential for birds survival in prolonged cold weather.
The second of the Tree Sparrow’s ‘big 3’ requirements is availability of suitable, protected nest sites. Tree Sparrows will nest in farm buildings, holes in trees, nest boxes and even dense bushes. Farm Researcher Derek Gruar, with the help of volunteers like Mo Reeves, has been placing nest boxes at selected locations around the farm, “hopefully these next boxes might help Tree Sparrows re-colonise the area for the first time in 30-40 years” said Derek.
Image 2: Derek, helped by Mo, puts up tree sparrow box 8 (TS8) at the far southern end of the farm, near where Tree Sparrows were seen feeding in November.
In all, ten Tree sparrow boxes have been positioned around the farm, providing a valuable supplement to natural nest sites in the area, such as old trees with nest holes and large, thick hedges.
Image 3: Box TS8 (top right) is located adjacent to an area of woodland that was known to support a population of breeding Tree Sparrows in the 1960’s. Could 2015 be the year of their return?
Image 4: Box TS9, just visible halfway up on the left trunk, located next to a larger starling nest box.
Image 5: Looking North across a sown wild bird mix towards the wood and up along the field boundary with wide grass margins.
In addition to winter food and safe nesting habitat, Tree Sparrows need a good supply of insects to feed their young if they are to breed successfully. Insect food for chicks in spring and summer is therefore the third of the ‘Big 3’ requirements for Tree Sparrows on lowland and mixed farmland. On Hope farm, grass margins (like that seen in the distance in Image 5) and flower-rich margins provide habitat for insects which the adults bring back to the nest. Insects may also be gleaned from hedgerows, conservation headlands, waterside vegetation and crops.
Crucially the ‘Big 3’, winter food, nesting habitat and spring/summer food, are all present at Hope Farm, and the appearance of the Tree Sparrows this winter offers some hope that pairs may ‘hang around’ and prospect for nest sites in the next few weeks. The return of the Tree Sparrow as breeding species at the Farm after nearly 4 decades would be truly momentous, so watch this space for further updates.
For more detailed information on how to manage for Tree Sparrows on lowland arable and mixed farms, including links to downloadable materials check here:
To find out more about the work at Hope Farm see the website here or look out for updates on this blog.
On Twitter follow @AgriODowd for the latest news on RSPB related Farming stories.
By Rebecca O’Dowd, RSPB Agricultural Communications Manager.
Image 1: Holly Neville-Smith. Images 2-5 Rebecca O'Dowd
* State of the UK’s Birds 2014: http://www.rspb.org.uk/Images/state-of-the-uks-birds_tcm9-383971.pdf