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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 81st 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 collected and processed in 2017. Demographic data contributed to several research studies during the year, including a review of the conservation status of Raven Corvus corax and the impacts of licensed control. This quantified the extent to which non-breeding birds could be removed without impacting overall population sustainability, as well as the data permitted, but noted that a better understanding of age-specific survival rates was required. Nest Record Scheme data contributed to a large-scale collaborative study investigating the impact that temperature and rainfall have on the timing of events throughout the annual cycles of 10 000 animal and plant species across different trophic levels. The results indicated that the speed of response was greatest at low trophic levels. Future changes under a range of emission scenarios were estimated; these results indicated that advances in timing would be greatest for primary consumers. A statistical method was developed, using nest record data, to quantify nest failure, taking into account uncertainties generated during data collection. The method was applied to Blackbird Turdus merula records to compare survival rates of nests in gardens with those in the wider countryside. Survival in suburban areas was found to be higher than in urban or rural areas, and nests survived better in wetter conditions across all habitats. In order to quantify any welfare impacts of capturing wild birds, we examined the frequency with which passerines were reported to have died either whilst in the net or during handling. Analyses of capture data submitted from 2005 to 2013 indicated that the average mortality rate is around 0.1%, and that this is consistent between years. Most fatalities occurred before individuals had been extracted from the nets and juveniles appeared to be at greater risk than adults. In 2017, 135 CE sites submitted data. Long-term (1984–2016) declines in abundance were observed in four migrant, one partial migrant and one resident species and concurrent increases in abundance continued to be recorded in two short-distance migrants and four resident species. There was no change to the 10 species which exhibited significant long-term declines in productivity; only one species, Chaffinch Fringilla coelebs, exhibited a significant long-term increase in productivity. Compared to the five-year mean (2012–16), the abundance of six species increased significantly in 2017; Treecreepers Certhia familiaris were seen in greater numbers in 2017 than in any other year since CES monitoring began. Conversely, the abundance of six species fell significantly in 2017, with Chaffinch and Greenfinch Chloris chloris numbers at their lowest since CES monitoring began. Productivity increased significantly for three species in 2017 and decreased for eight species. The only significant change in survival rates between 2017 and the five-year mean was for Wren Troglodytes troglodytes, although the survival rate for Song Thrush Turdus philomelos was at its highest. The number of Retrapping Adults for Survival submissions fell slightly in 2017 to 195; 11 projects ran for the first time. In total, 58 species were monitored, with Pied Flycatcher Ficedula hypoleuca (20 projects), House Sparrow Passer domesticus (16), Starling Sturnus vulgaris (15) and Sand Martin Riparia riparia (11) continuing to be the most-studied species. Once again, over a million birds (1 020 356) were ringed during the year, comprising 165 565 nestlings, 500 580 first-year birds, 321 945 adults (birds in their second calendar year or older) and 32 266 birds where the age could not be determined. In addition, there were 242 719 recaptures of ringed birds at or near the ringing site. In total, 41 049 recoveries (birds found dead, recaptured or resighted at least 5 km from the place of ringing) of BTO-ringed birds were reported in 2017. 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 2017 exceeded 4 0 000 for the eighth consecutive year, with a total of 43 570 records received. Mean laying dates for 22 species were significantly earlier than the five-year mean (2012–16) with none of the 52 species analysed laying significantly later. There was a significant increase in breeding success (fledglings per breeding attempt) for two species in 2017, compared to the five-year mean, with one decreasing significantly. Permits or licences to disturb breeding birds on Schedule 1 of the Wildlife and Countryside Act 1981 (as amended), were prepared and issued to 580 ringers and nest recorders in 2017. During 2017, the use of special methods was authorised for 584 marking projects and 67 trapping projects, a 4% decrease from 2016. [ABSTRACT FROM AUTHOR]