Search

This is the 78thannual report of the British Trust for Ornithology's Ringing Scheme, incorporating the report of the Nest Record Scheme and covering work carried out and data processed in 2014.Many species have shifted their range towards the Earth's poles in response to global temperature increases. Data from four European Constant Effort Sites (CES) ringing schemes were examined to determine the impact of large-scale temperature variations on productivity in a group of seven migratory bird species to determine the potential for future range changes. Increased productivity at northern sites was apparent only in Reed WarblerAcrocephalus scirpaceus, although there was evidence of local adaptation in six species, suggesting that the rate of northward range shift may be constrained by adaptation to local climatic conditions.A study on the role of carry-over effects in RedstartPhoenicurus phoenicurus, Spotted FlycatcherMuscicapa striataand Wood WarblerPhylloscopus sibilatrixfound that carry-over effects from passage regions impacted on the timing of breeding more strongly than climate on the breeding grounds and that warmer conditions in the breeding area were not associated with reduced productivity.Work on the impact of environmental variables on annual population changes found that, over 40 years, the strongest impact on migrants was rainfall in the Sahel. Over 25 years, positive population changes in response to wetter winters were found for 12 of 16 species studied.Data were submitted for 132 CE sites in 2014. Long-term (1984–2013) population trends derived from the CES data have changed little in the past year. The abundance of five migrant species and five resident species decreased significantly in 2014 compared to the five-year mean (2009–13). The abundance of five of these species (Willow WarblerPhylloscopus trochilus, Sedge WarblerAcrocephalus schoenobaenus, BlackbirdTurdus merula, ChaffinchFringilla coelebsand GreenfinchChloris chloris) was at its lowest since CES monitoring began. There were significant increases in abundance for three species. Productivity decreased significantly in Willow TitPoecile montanacompared to the five-year mean (2009–13), but there were significant increases for eleven species (seven residents and four migrants),with productivity for Reed Warbler, Blackbird and BullfinchPyrrhula pyrrhulaat its highest since CES began. There were only two significant changes in survival in 2014.A total of 176 Retrapping Adults for Survival (RAS) projects were active in 2014, the highest total ever, with 22 new projects starting, 17 of which involved RAS target species. Projects were carried out on Tawny OwlStrix alucoand SwiftApus apusfor the first time.The total number of birds ringed in 2014 exceeded one million for the third time (1,047,026) and comprised 520,477 first-year birds, 303,086 adults (birds in their second calendar year or older), 29,799 unaged birds and 193,664 nestlings. In addition, there were 226,303 recaptures of ringed birds at or near the ringing site.In total, 28,187 recoveries of BTO-ringed birds were reported for 2014. A selection of recoveries that have extended our knowledge of movements is presented, as well as longevity records established during the year. The numbers of birds recovered between 2010 and 2013 have been revised as data submitted as retraps have been examined and some have been reclassified as recoveries.For the fifth year running, annual totals of nest records surpassed 40,000, reaching 46,382. Mean laying dates for 55 species were significantly earlier than the five-year mean (2009–13) with 19 species laying significantly later than the five-year mean. Breeding success (fledglings per breeding attempt) increased significantly for 14 species, with none showing a decrease.Nearly 600 permits/licences to disturb breeding birds on Schedule 1 of the Wildlife and Countryside Act (1981), were prepared/issued in 2014, a small increase from 2013.The use of special methods was authorised for 398 marking projects and 47 trapping projects in 2014, 12% fewer than in 2013. [ABSTRACT FROM PUBLISHER]

This is the 77th annual report of the British Trust for Ornithology's Ringing Scheme, incorporating the report of the Nest Record Scheme and covering work carried out and data processed in 2013. In recent years the schemes have focused on the collection of demographic data as part of our Integrated Population Monitoring programme. We expanded (from 10 to 17) the number of species for which we were able to construct integrated models and identified differences in the relative contributions of recruitment and adult survival to population change between increasing and decreasing species. Recruitment of young into the breeding population can be difficult to estimate. We investigated the use of proportions of birds in their second calendar year, or older, caught in the early summer using Blackbird Turdus merula as a model. Results showed that recruitment was a more important determinant of population change than survival. Changes in phenology are being documented widely and we carried out analyses looking at the timing of moult and reproduction in selected passerine species. Patterns in timing and duration of moult varied between resident species but were more aligned within migrant species, which also moulted faster. Temperature on spring breeding grounds accounts for more variation between years in breeding phenology than precipitation rates on the wintering grounds in 19 migrant species but neither climate variable affected clutch size. We continued to emphasise the value of targeted ringing and nest recording; increased participation in our structured ringing schemes has provided additional opportunities to improve the quality of demographic monitoring. Long-term (1984–2012) population trends derived from the Constant Effort Sites (CES) data have changed little in the past year. Three of the eight migrant species monitored by CES showed significant increases in productivity compared to the five-year average, although Sedge Warbler Acrocephalus schoenobaenus recorded its second-lowest productivity since CES began in 1983. Breeding performance of residents was mixed, with juvenile:adult ratios for some early breeders significantly lower than during the preceding five years, but significantly higher for some late breeders; one late-breeding resident species, Bullfinch Pyrrhula pyrrhula, had its highest productivity since CES began. Data were submitted for 124 sites. The number of active RAS projects in 2013 was 154, with 22 new projects, 13 of which involved RAS target species. The total number of birds ringed in 2013 decreased slightly (952,750) compared to 2012 and comprised 424,401 first-year birds, 355,278 adults (birds in their second calendar year or older), 19,776 unaged birds and 153,295 nestlings. In addition, there were 241,111 recaptures of ringed birds at or near the ringing site. The reduction in numbers ringed compared to 2012 was probably a result of weather events in 2013. In 2013, there were 465 colour-marking projects registered, covering a total of 110 species; 65 new projects were registered during the year. There were 21,275 recoveries of BTO-ringed birds: the highest total ever. A selection of recoveries that have extended our knowledge of movements is presented, as well as longevity records established during the year. In total, 40,384 nest records were submitted. Of these, 82% originated from England, 8% from Wales and 9% from Scotland, the remaining 1% divided between Northern Ireland and the Republic of Ireland. This was a reduction on the 2012 totals and probably reflected the poor start to the breeding season caused by the exceptionally cold weather in early spring. Long-term trends in nest productivity (fledglings per breeding attempt) were significant for 44 of the 72 species monitored. Of these, thirteen trends were negative, indicating a decline in breeding success over time. [ABSTRACT FROM AUTHOR]