Watch the birdies; It's National Nest Box Week and twitchers are needed to study birds' changing habits. JANET TANSLEY finds out the details.
BTO volunteers have been monitoring nests for more than 75 years and this month, which includes National Nest Box Week (ending on February 21), it is encouraging families to put up nest boxes so that they can contribute to this long-running national study.
The height |box will species might Dr Dave Leech, a Senior Research Ecologist at the BTO, says: "We know that rising spring temperatures are driving this trend, but what are the repercussions? "Are earlier breeding birds able to keep pace with their insect prey, the appearance of which is also advanced by the warming climate? Or do they still miss the boat, leading to starvation of the chicks? "In order to answer these questions, we urgently need people to monitor nests of common birds, particularly in gardens where data on breeding attempts is surprisingly scarce."
He adds: "As well as providing a suitable site, nest boxes provide an ideal opportunity to record the progress of the eggs and young.
"So, while putting up a box may have some local benefit, collecting data on what's inside for BTO helps bird populations far beyond the boundaries of your own garden."
To find out more about nest boxes and how you can record what happens in your own visit www.bto.org/volunteer-surveys/nbc.
Hazel Evans, who runs the BTO's Nest Box Challenge, an online survey where members of the public can submit data about nesting attempts, gives us her top tips for putting up a nest box. 1. Wherever possible try and put the box up with the entrance hole facing north, or north-east. This will ensure that the nest box is not in full sunlight for most of the day, helping to keep incubating parents and growing chicks cool.
of your nest influence what move into it 2. Think about the location carefully, close to the top of a wall where cats might be able to access the box should be avoided, and do not put one too close to a feeding station.
3. The ideal height from the ground for a nest box varies with the species. House sparrows seem to prefer a higher nest box, close to the eaves if fitting on a building, similarly starlings, although these will use nest boxes located on trees too. For blue and great tits, head height is high enough as long as tip 2 is followed. Open-fronted boxes, preferred by robins, can be located low to the ground in cover but locate higher if the garden is visited by cats.
4. If making your own box use wood in excess of 15mm in thickness - this will ensure the box doesn't warp and will also provide insulation and warmth when the weather turns cold. Different species need different size entrance holes.
Starling - 45mm | House sparrow - 32mm | Great tit - 28mm | Blue tit - 25mm | Robin - open-fronted |5. Consider fitting an easily removable lid, or one that you can open to view your nest box.
This will make it easier to record what is happening in your nest box, should you want to, and make it easier to clean out at the end of the season.
| The height of your nest |box will influence what species might move into it
You must |ensure that your nesting box is made of thick enough wood to keep it warm in the cold weather