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This is the 80th 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 2016. BTO and JNCC have used seabird population data to investigate how demographic processes drive population changes, enabling improved population models to be produced. These population models were used to help quantify the risks associated with large-scale infrastructure projects (e.g. windfarms) and recommendations were made concerning approaches to be used in particular circumstances. Density dependence in seabirds, and its potential impact on population models, was also reviewed but little evidence of significant effects was found. Research on the demographic causes of declines in migratory species, undertaken in collaboration with the University of East Anglia, focused on population changes in Willow Warblers Phylloscopus trochilus. Data from the Nest Record Scheme (NRS), Constant Effort Sites scheme (CES) and the Breeding Bird Survey were combined; the results showed that reduced productivity levels in Willow Warblers in the south of Britain were driving the decline. In 2016, 134 CE sites submitted data. Five migrant and two resident species exhibited long-term (1984-2015) declines in abundance while four migrant and six resident species showed declines in productivity. Compared to the five-year mean (2011-15), the abundance of 10 species increased significantly in 2016 with Cetti's Warbler Cettia cetti, Chiffchaff Phylloscopus collybita, Wren Troglodytes troglodytes and Robin Erithacus rubecula abundance at its highest since CES monitoring began. The abundance of three species fell significantly in 2016. Productivity increased for one species in 2016 and decreased significantly for 16 species. Survival rates increased significantly for three species and fell significantly for one. For the first time, the number of Retrapping Adults for Survival submissions passed 200. A total of 59 species were monitored and 24 projects ran for the first time. The most-studied species were Pied Flycatcher Ficedula hypoleuca (23 projects), House Sparrow Passer domesticus (17), Sand Martin Riparia riparia (15) and Starling Sturnus vulgaris (13). Over a million birds (1 051 629) were ringed during the year, comprising 157 653 nestlings, 490 796 first-year birds, 370 019 adults (birds in their second calendar year or older) and 33 161 birds where the age could not be determined. In addition, there were 255 898 recaptures of ringed birds at or near the ringing site. In total, 40 257 recoveries (birds found dead, or recaptured or resighted at least 5 km from the place of ringing) of BTO-ringed birds were reported in 2016. The Appendix highlights a selection of recoveries that have extended our knowledge of movements, as well as longevity records established during the year. NRS submissions in 2016 exceeded 45 000 for the third consecutive year, with a total of 46 514 records received. Mean laying dates for five species were significantly earlier than the five-year mean (2011-15) with 10 species laying significantly later. Three species displayed a significant increase in breeding success (fledglings per breeding attempt) in 2016 compared to the five-year mean, with four decreasing significantly. Permits/licences to disturb breeding birds on Schedule 1 of the Wildlife and Countryside Act 1981 (as amended), were prepared/issued to 587 ringers and nest recorders in 2016. During 2016, the use of special methods was authorised for 559 marking projects and 73 trapping projects, a 13% increase on 2015 [ABSTRACT FROM AUTHOR]

This is the 79thannual 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 2015. Constant Effort Sites (CES) data from across Europe, relating to eight common warblers, were analysed to investigate large-scale variation in survival rates and showed that changes in survival outside the breeding season are not a key driver of long-term population trends. Retrapping Adults for Survival (RAS) seabird data sets were reviewed to understand their ability to supplement geographically limited, long-term studies carried out by professionals. Most RAS studies re-encountered sufficient numbers of seabirds to estimate average survival rates; however, only those with re-encounter rates of around 40% were able to detect changes in survival rates efficiently. Over 100,000 nest records, relating to four insectivorous woodland passerines, were used to investigate changes in laying dates in response to temperature. Laying dates advanced by 2.3–4.8 days per °C rise in temperature, suggesting that these species may be able to change their laying dates in response to climate changes, even if the rate of climate change is rapid. Over 10,000 phenological data sets, including laying dates for 37 bird species, were used to look at the mechanisms behind species’ responses to changes in climate. Primary producers and primary consumers advanced timing of breeding more quickly than secondary consumers, potentially leading to a greater mismatch between the timing of breeding in birds (secondary consumers) and their prey availability under future climate-change projections. Data were received for 134 CE sites in 2015. Long-term (1984–2014) population trends derived from the CES data identified five migrant species and four resident species that have decreased significantly in abundance over this period. Abundance of three species decreased significantly in 2015 compared to the five-year mean (2010–14) with WhitethroatSylvia communisabundance at its lowest since CES monitoring began. There were significant increases in abundance for 12 species, with GoldfinchCarduelis carduelisat its highest since CES monitoring began. Productivity decreased significantly in ten species and increased significantly in three species compared to the five-year mean (2010–14); productivity for Willow WarblerPhylloscopus trochiluswas at its lowest since CES began. There were no significant changes in survival in 2015. The total number of active RAS projects increased again in 2015; 190 submissions were received, including data from 23 new projects. Projects were carried out on 57 species, with Pied FlycatcherFicedula hypoleuca(23 projects), Sand MartinRiparia riparia(15) and House SparrowPasser domesticus(20) still the most-studied species. The total number of birds ringed in 2015 was just under one million (987,253) and comprised 472,462 first-year birds, 319,230 adults (birds in their second calendar year or older), 27,993 unaged birds and 167,568 nestlings. In addition, there were 236,540 recaptures of ringed birds at or near the ringing site. In total, 32,253 recoveries (birds found dead, or recaptured or resighted at least 5 km from the place of ringing) of BTO-ringed birds were reported in 2015. A selection of recoveries that have extended our knowledge of movements is presented, as well as longevity records established during the year. In total, 48,957 nest records were received for 2015, the highest annual submission since the Scheme began in 1939. Mean laying dates for five species were significantly earlier than the five-year mean (2010–14) with nine species laying significantly later. Only one species showed a significant increase in breeding success (fledglings per breeding attempt) in 2015, with four decreasing significantly. A total of 612 permits/licences to disturb breeding birds on Schedule 1 of the Wildlife and Countryside Act 1981 (as amended), were prepared/issued in 2015, a small increase from 2014. During 2015, the use of special methods was authorised for 489 marking projects and 68 trapping projects, 25% more than in 2014. [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]

This is the 76th annual report of the British Trust for Ornithology's Ringing Scheme, covering work carried out and data processed in 2012. Demographic integrated population monitoring has been the focus of the Scheme priorities in recent years and models that integrate ringing and nest record data and abundance trends were built for ten species for which sufficient data were available. Population drivers vary between species but they can be split between changes in breeding success, survival, or both. Multi-brooded species exhibited more seasonal variation in reproductive output than single-brooded species. In particular, migratory species showed a seasonal decrease in fledgling output, as do single-brooded species while residents generally showed a seasonal increase in productivity. Constant Effort Site (CES) data showed long-term (1984–2011) declines in four long-distance migrants and five resident species. However, four species (two short-distance migrants and two residents) have increased over the same period. Productivity of migrants monitored by CES was poor in 2012: seven of the eight species showed significant reductions in productivity compared to the five-year average and had the lowest productivity since CES began in 1983. Breeding performance of resident birds was low in 2012, with juvenile:adult ratios significantly lower than those calculated over the preceding five years for 10 of the 16 species. The number of CE sites increased in 2012, with data submitted for 125 sites, the highest total for a decade. The number of active RAS projects increased to 163 in 2012, with 21 new projects, eight of which involved RAS target species. In 2012 the total number of birds ringed (970,957) was the second highest recorded, and included 408,225 first-year birds, 377,199 adults (birds in their second calendar year or older), 23,772 unaged birds and 161,761 nestlings. In addition, there were 249,551 recaptures of ringed birds at or near the ringing site. The reduction in numbers ringed compared to 2012 was probably the result of the record wet weather that most of Britain & Ireland experienced in spring and summer 2012. A total of 18,693 BTO-ringed birds were recovered in 2012, which was lower than in 2011 but higher than in any previous year. This is the result of an increased number of birds ringed in the past 10 years, an increasing number of colour-ringed and tagged birds and subsequent resightings, more ringers within the Ringing Scheme, efforts to increase reports from members of the public of both metal and colour-ringed birds and an improvement in the way recoveries are processed. Recoveries of 22 BTO-ringed and 11 foreign-ringed individual birds that have extended our knowledge of movement of the species or constitute a new longevity record are presented. In total 44,895 nest records were submitted in 2012, the highest annual submission since the scheme began. Of these, 81% originated from England, 9% from Wales and 9% from Scotland, the remaining 1% divided equally between Northern Ireland and the Republic of Ireland. Submissions from England, Scotland and Northern Ireland have all risen by similar proportions since 2007 (18–22%), while those from Wales have increased by 34% over the same period. Long-term annual productivity trends have been calculated for three additional species. Long-term productivity trends were significant for 40 of the 72 species monitored and nine of these trends were negative, indicating a decline in breeding success over time. [ABSTRACT FROM AUTHOR]

This is the 75th annual report of the British Trust for Ornithology's Ringing Scheme, covering data received and work carried out in 2011. A review of priorities for the Scheme identified the need to increase submission of nest records through the Nest Record Scheme and to extend the network of Retrapping Adults for Survival (RAS) studies. Collection of different demographic parameters from the same site (eg nest records, numbers of breeding pairs, adult survival, etc) can provide a powerful tool to identify reasons for population change. Constant Effort Sites (CES) data showed long-term declines in abundance for four migrants (Willow Warbler Phylloscopus trochilus, Lesser Whitethroat Sylvia curruca, Sedge Warbler Acrocephalus schoenobaenus and Reed Warbler Acrocephalus scirpaceus) and three resident species (Willow Tit Poecile montana, Song Thrush Turdus philomelos and Reed Bunting Emberiza schoeniclus). Robin Erithacus rubecula and Reed Bunting had the lowest survival rates since CES began and survival-rate estimates were also significantly below average for Long-tailed Tit Aegithalos caudatus and Wren Troglodytes troglodytes, two small resident species that are particularly vulnerable to cold weather. Abundance of Blue Tit Cyanistes caeruleus, Great Tit Parus major, Goldfinch Carduelis carduelis and Bullfinch Pyrrhula pyrrhula recorded by CES increased. Nine of the 16 resident species covered by CES also had higher-than-average productivity, in particular the highest ever recorded for Dunnock Prunella modularis, Chaffinch Fringilla coelebs and Bullfinch. The number of Constant Effort Sites increased in 2011, with a higher percentage of reedbed habitat covered by the scheme, but fewer dry and wet scrub sites. In 2011 the number of RAS projects increased by 34 to 158. Survival trends were generated for 46 species and the use of colour marks has been promoted to increase the resighting probability of trap-shy species such as House Sparrow Passer domesticus and Starling Sturnus vulgaris, and for species with low recapture probability such as seabirds. As in 2010, the total number of birds ringed in 2011 (1,151,665) was the highest ever. It included 540,696 first-year birds, 383,136 adults (birds in their second calendar year or later) and 27,495 unaged birds. All ringing data for 2011 were computerised. In addition, there were 166,061 recaptures of ringed birds at or near the ringing site. The increased numbers of fully grown birds ringed is probably due to three main factors: high survival of some species, as suggested by CES results, combined with high productivity in 2011 and the increasing number of ringers in the Scheme catching higher numbers of birds. In total 20,702 BTO-ringed birds were recovered (found dead or recaptured away from the ringing site) in 2011, the highest ever as a result of the increased number of birds ringed in the past decade, combined with efforts to increase reports of ringed birds by the public, an increasing number of colour-ringing projects and associated resightings, and a change in the way recoveries are processed. Recoveries of 17 BTO- and 13 foreign-ringed birds that have extended our existing knowledge of movements of a species, are unusual movements, or are a new longevity record are also presented. In 2011 40,845 nest records were submitted (over 70% electronically), the highest total since 1998. Of these, 82% originated from England, 9% from Wales and 8% from Scotland, with the remaining 1% divided equally between Northern Ireland and the Republic of Ireland. Long-term nest productivity trends (1966–2010) were significant for 36 of the 71 species for which sufficient data were available, and seven of these (Nightjar Caprimulgus europaeus, Tree Pipit Anthus trivialis, Willow Warbler, Bullfinch, Coal Tit Periparus ater, Treecreeper Certhia familiaris and Chaffinch) showed a significant decline over time. The 2011 breeding season was characterised by an early start compared to the previous five years, possibly due to the warmest April on record. [ABSTRACT FROM AUTHOR]

This is the 74th annual report of the British Trust for Ornithology's Ringing Scheme, covering data received and work carried out in 2010. Analytical work in the year concentrated on considering how we can improve demographic monitoring, an increasing focus for the Scheme. A broad review of the availability of demographic and count data for terrestrial-breeding species was carried out. This work will be further extended in 2011. To inform conservation we need to build population models for species with a range of ecologies and occupying different habitats. Reports of ringed birds make a large contribution to our understanding of two key demographic parameters – survival and dispersal. An analysis of Chiffchaff Phylloscopus collybita recovery data from across Europe suggested they are tending to migrate south later and north earlier over time. There is also a suggestion that the migratory journey is shortening. Analysis of biometrics of birds wintering in Britain showed that they are largely from the breeding populations of the nominate race in Britain and the near Continent. Constant Effort Sites (CES) data showed that, for seven of the 24 species monitored, there was a significant decrease in adult abundance compared to the mean of the previous five years. As six of these species were residents, this may have been a result of the second severe winter in succession, although there was a short-term increase for Long-tailed Tit Aegithalos caudatus, which is usually affected by cold winters. The adult abundance of several long-distance migrants also increased. A long-term decline (1984–2000) is, however, still evident for five migrants and three residents, although for Willow Tit Poecile montana and Linnet Carduelis cannabina the sample sizes are low. The abundance of the short-distance migrants, Blackcap Sylvia atricapilla and Chiffchaff, has increased, possibly as a result of climate change. Productivity was higher than the mean of the previous five years for 12 species with the long-term trend increasing for eight species – four migrants and four residents. The only significant decreases were for Blackbird Turdus merula and Long-tailed Tit, possibly as these species breed early and were affected by the severe winter. Dry summer weather is also likely to have contributed to the low productivity of Blackbirds and increasingly dry summers may be implicated in the long-term declines in productivity for both Blackbird and Song Thrush Turdus philomelos. Long-term trends in survival rates were produced using CES data for the first time in 2010. These suggested that the cold winter weather in 2009–10 reduced the survival rate of resident ground-feeding insectivores such as Dunnock Prunella modularis, Blackbird, Wren Troglodytes troglodytes and Robin Erithacus rubecula. Survival rates of migrants were relatively high, particularly for Garden Warbler Sylvia borin and Sedge Warbler Acrocephalus schoenobaenus, possibly as a result of good conditions on the wintering grounds or passage sites. Data for 129 Retrapping Adults for Survival (RAS) studies covering 39 species were submitted. For the first time we were able to calculate good or moderate annual estimates of survival for 18 species. A list of priority species for RAS was developed and promoted to volunteers. The total number of birds ringed (1,096,533) was the highest ever recorded, as well as being the first time the annual total has surpassed 1 million. It was 28% higher than the mean of the previous five years and 17% higher than in 2009. However, the total number of pulli ringed in 2009 (193,554) was only 12% higher than the preceding five-year mean, while that of fully grown birds (902,979) was 32% higher. The recovery total (17,315) was also the highest ever. This is partly due to changes in the way that records of colour-ringed and other specially marked birds are stored, but also reflects the increasing number of birds being ringed by a growing number of ringers. The number of recoveries of foreign-ringed birds (2,427) was higher than the mean of the preceding five years; this figure was influenced by varying response times of different ringing schemes, but was also partly as a result of multiple sightings. Recovery details for 221 individual birds are given in the final section of the report. They include movements that confirm suspected or known migration patterns, unexpected movements and longevity records. [ABSTRACT FROM AUTHOR]

The article reports on the 2009 bird Ringing Scheme of the British Trust for Ornithology (BTO) covering Great Britain and Ireland to better understand population change. Due to low productivity in 2007 and 2008 and freezing winters, there were decreases in species such as Wren Troglodytes troglodytes, Sedge Warbler Acrocephalus schoenobaenus and Reed Warbler A. scirpaceus. The number of birds ringed was the highest recorded at 935,867 and recovery total was also high at 14,643.