88 nest boxes were monitored at Charlecote Park in 2013. The scheme was originally started by Dave Oldham and Denis Harris who began erecting boxes in April 2003. Since then the scheme has been expanded and now includes:
- 3 boxes specifically designed for barn owls
- 2 boxes for kestrels
- 2 boxes for little owls
- 21 large boxes for jackdaws, stock doves and tawny owls
- 55 small boxes for blue tits and great tits
- 5 open fronted boxes for robins and spotted flycatchers.
Natural cavities are examined as and when found. Swallows that use the low stores in the yard area are also monitored.
Over the seven year period that the boxes have been closely monitored ten species have now used them – Mandarin duck, kestrel, stock dove, barn owl, tawny owl, jackdaw, blue tit, great tit, coal tit and robin. Little owl and treecreeper have used natural cavities.
Since 2007 1163 young have been ringed and records kept of all nest visits. Electronically compiled Nest Record Cards are sent to the British Trust for Ornithology; 64 were completed in 2013 (67 in 2012, 65 in 2011, 51 in 2010, 40 in 2009, 49 in 2008 and 41 in 2007).
With persistent easterly and north-easterly winds, temperatures between March and June 2013 were up to four degrees below average, resulting in a very late spring. The cold spring resulted in many species starting the breeding cycle later, the British Trust for Ornithology (BTO) reported that Blue Tit and Great Tit both delayed egg production by 12 days. For some species, mean first egg dates in 2013 were comparable with those exhibited in the 1960s. Nationally Blue Tit and Great Tit also fledged significantly fewer chicks in 2013, with numbers per nest falling by 7% and 12% respectively relative to the five-year mean. Low spring temperatures are generally beneficial for these species as they delay caterpillar emergence and development, increasing food availability during the nestling period; in recent warm years, there has been a tendency for invertebrate numbers to peak while birds are still on eggs. The poor breeding performance in 2013 was largely due to a reduction in clutch sizes, however, which suggests that the cold weather prior to laying may have had a negative impact on female condition and therefore on the average number of eggs laid.
Extensive floods in the early part of 2013, a spell of snow and cold weather in late March, with continuing low temperatures mentioned above, coupled with low vole numbers resulted in a poor breeding season for birds of prey. The BTO reported that in late March, when barn owls should be thinking of breeding, they had seen an exceptional rise in the number of dead ringed birds reported, the cause of death in most cases was starvation, a sure sign that food resources were very low. Snow, wind and flooding hinders the ability for birds of prey to find rodents and small mammals and if female birds of prey are unable to get into breeding condition many pairs may decide not to breed. Colin Shawyer of the Barn Owl Conservation Network reported that “2013 appears to have been the poorest breeding season for barn owls in Britain since 1958” and initial results from the BTO’s nest record scheme points to low fledging success in kestrel, barn owl and tawny owl for the second year running. The number of nest record card submissions in 2013 for barn owl and tawny owl stands at about 25% of the normal total .
A summary of the nests found and monitored in Charlecote Park over the seven year period can be found below.
Our thanks to our trained specialists, Dave Oldham, Denis Harris, Keith Ashfield and Roger Juckes for this report.
Are you a keen twitcher? Blogger ‘Black Country Birder’ wrote a post following their visit. Why not find out what they spotted?
Have a look at our website for more info on the wildlife that calls Charlecote ‘home’.