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This is the 85th 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 2021. In 2021, 105 Constant Effort Sites submitted data for the year. Long-term (1984–2020) declines in abundance were observed for five migrant, one partial migrant and five resident species, while long-term increases in abundance were recorded for two short-distance migrants and seven resident species. Ten species are exhibiting significant long-term declines in productivity, while only Chaffinch Fringilla coelebs shows a significant long-term increase. Long-term trends in survival indicate increases for 12 species and declines for seven. Short-term trends, which compare the current year to the five-year mean for 2016–20, show that the abundance of seven species increased significantly in 2021, with one species, Treecreeper Certhia familiaris, being recorded in higher numbers than in any previous year of CES monitoring. Significant decreases in abundance were recorded for four species. Productivity decreased significantly for seven migrant and 11 resident species in 2021, with six species recording their lowest breeding success since CES monitoring began; no species recorded a significant short-term increase. Significant changes in survival rate were observed for two species in 2021 compared to the five-year mean, with Song Thrush Turdus philomelos increasing and Chaffinch both declining and recording its lowest survival rate ever. The Garden CES trial continued in 2021, with 60 sites submitting data. The new winter ringing project also continued in 2021, with submissions received from 126 sites. The number of Retrapping Adults for Survival projects that were able to run and submit data in 2021 was 192, with data from one more project submitted too late to be included in this report and another four active projects unable to operate. In total, 60 species were monitored, with Starling Sturnus vulgaris (21 projects), House Sparrow Passer domesticus (20 projects), Pied Flycatcher Ficedula hypoleuca (19 projects), Reed Warbler Acrocephalus scirpaceus (nine projects) and Sand Martin Riparia riparia (nine projects) the species most studied. A total of 900 131 birds were ringed during the year, comprising 146 458 nestlings, 438 342 first-year birds, 291 127 adults (birds in their second calendar year or older) and 24 204 birds whose age could not be determined. In addition, there were 210 147 recaptures of ringed birds at or near the ringing site. In total, 42 328 recoveries (birds found dead, recaptured or resighted at least 5 km from the place of ringing) of BTO-ringed birds were reported in 2021. The Appendix highlights a selection of recoveries that have extended our knowledge of movements, as well as longevity records established during the year. A total of 41 096 NRS submissions were received in 2021. Mean laying dates for 2021 were significantly later than the average for 13 species and only one species significantly advanced its laying date. Five species displayed a significant change in fledglings per breeding attempt, with two recording increased productivity and three reduced productivity. Permits or licences to disturb breeding birds on Schedule 1 of the Wildlife and Countryside Act 1981 (as amended) were prepared and issued to 602 ringers and nest recorders in 2021. During 2021, 2588 marking endorsements, 868 sampling endorsements and 214 trapping endorsements were issued in the UK and overseas. [ABSTRACT FROM AUTHOR]

This is the 84th 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 2020. An analysis of Curlew Numenius arquata ringing records was carried out to investigate recent declines. Results showed that survival rates are high, so current population declines are more likely to have been driven by low productivity. To reverse the recent population declines, breeding success would need to increase and effective conservation strategies will be needed to maintain the high levels of survival. We examined the potential opportunities and challenges of using winter ringing records to produce survival estimates, as well as other outputs such as age ratios and recruitment, by analysing 2 641 352 encounter records from the winters of 2007/08 to 2017/18: winter-to-winter survival analyses on adult birds were undertaken, initially on 44 species. Results indicated that fortnightly ringing sessions should yield sufficient data to produce useful survival estimates. This research identified a number of potential analytical and methodological options for future development. Covid-19 restrictions limited the amount of fieldwork carried out in 2020; consequently, only 72 CE sites submitted data for the year. Long-term (1984–2019) declines in abundance were observed for five migrant, one partial migrant and four resident species while long-term increases in abundance were recorded for two short-distance migrants and six resident species. Six species are exhibiting significant long-term declines in productivity while only Chaffinch Fringilla coelebs shows a significant long-term increase. Long-term trends in survival indicate increases for 10 species and declines for nine. Short-term trends, which compare the current year to the five-year mean (2015–19), show that the abundance of 10 species increased significantly in 2020, with three species being recorded in higher numbers than in any previous year since CES monitoring began. Significant decreases in abundance were recorded for only two species. Productivity decreased significantly for one migrant and five resident species in 2020; no species recorded a significant increase. Productivity was lower in 2020 than in any previous CES year for Blue Tit Cyanistes caeruleus and Great Tit Parus major. Significant changes in survival rate were observed in two species in 2020 compared to the five-year mean, with Bullfinch Pyrrhula pyrrhula increasing and Blackbird Turdus merula decreasing. A new habitat was added to the suite of standard CES habitats in 2020 in the first year of a Garden CES trial. Submissions were received from 92 sites. A new winter ringing project was also launched in 2020, following a similar methodology to CES. Submissions were received from 111 sites. The number of Retrapping Adults for Survival projects that were able to run and submit data in 2020 was 146, from 200 that were registered. In total, 60 species were monitored, with Pied Flycatcher Ficedula hypoleuca (20 projects), Starling Sturnus vulgaris (19), House Sparrow Passer domesticus (18), Sand Martin Riparia riparia (10) and Reed Warbler Acrocephalus scirpaceus (eight) the species most studied. A total of 930 091 birds were ringed during the year, comprising 98 500 nestlings, 523 777 first-year birds, 278 157 adults (birds in their second calendar year or older) and 29 657 birds whose age could not be determined. In addition, there were 212 414 recaptures of ringed birds at or near the ringing site. In total, 42 987 recoveries (birds found dead, recaptured or resighted at least 5 km from the place of ringing) of BTO-ringed birds were reported in 2020. The Appendix highlights a selection of recoveries that have extended our knowledge of movements, as well as longevity records established during the year. A total of 23 928 NRS submissions were received in 2020, far fewer than usual due to Covid-19 restrictions being in place during the height of the nesting season. As the seasonality of nest records was biased towards the end of the breeding season, after Covid-19 restrictions had lifted, it was not possible to generate meaningful NRS trends for 2020. Permits or licences to disturb breeding birds on Schedule 1 of the Wildlife and Countryside Act 1981 (as amended) were prepared and issued to 611 ringers and nest recorders in 2020. During 2020, the use of special methods was authorised for 1182 marking projects and 146 trapping projects. [ABSTRACT FROM AUTHOR]

This is the 83rd 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 2019. In 2019, 130 CE sites submitted data. Long-term (1984–2018) declines in abundance were observed for five migrant, one partial migrant and four resident species while long-term increases in abundance continue to be recorded for two short-distance migrants and four resident species. Seven species are exhibiting significant long-term declines in productivity while only Chaffinch Fringilla coelebs is exhibiting a significant long-term increase. Long-term trends in survival indicate increases for 14 species and declines for six. Compared to the five-year mean (2014–18), the abundance of eight species decreased significantly in 2019, with five species being recorded in lower numbers than in any previous year since CES monitoring began. Significant increases in abundance were recorded for six species. Productivity increased significantly for two migrant and six resident species in 2019 and decreased for only one species; Productivity rates were higher in 2019 than in any previous year for Chaffinch. Significant declines in survival rate were observed in one species in 2019 compared to the five-year mean; no species exhibited a significant increase. The number of Retrapping Adults for Survival submissions increased slightly in 2019 to 195. In total, 59 species were monitored, with Pied Flycatcher Ficedula hypoleuca (22 projects), Starling Sturnus vulgaris (17), House Sparrow Passer domesticus (16), Sand Martin Riparia riparia (11) and Reed Warbler Acrocephalus scirpaceus (10) the species most studied. A total of 1 050 520 birds were ringed during the year, comprising 181 766 nestlings, 518 575 first-year birds, 318 390 adults (birds in their second calendar year or older) and 31 789 birds whose age could not be determined. In addition, there were 243 775 recaptures of ringed birds at or near the ringing site. In total, 45 610 recoveries (birds found dead, recaptured or resighted at least 5 km from the place of ringing) of BTO-ringed birds were reported in 2019. The Appendix highlights a selection of recoveries that have extended our knowledge of movements, as well as longevity records established during the year. A total of 41 367 NRS submissions were received in 2019, higher than the previous season but otherwise the lowest annual total since 2013. Mean laying dates for 2019 were significantly earlier than the five-year mean (2014–18) for 12 of 52 species analysed and five species displayed a significant increase in breeding success (fledglings per breeding attempt). Permits or licences to disturb breeding birds on Schedule 1 of the Wildlife and Countryside Act 1981 (as amended), were prepared and issued to 547 ringers and nest recorders in 2019. During 2019, the use of special methods was authorised for 613 marking projects and 158 trapping projects. [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 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]

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]