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Biometrics, particularly wing length, are commonly used to assign the sex of many birds in species where the plumage is similar for males and females. Virtually all species show some measurement overlap between the sexes, however, and measurement error can add further uncertainty into data sets. This can result in individuals being misclassified as the wrong sex and introducing bias into subsequent analyses, particularly if the life histories of misclassified birds differ from those of others. We used the Marsh Tit Poecile palustris as a case study to examine potential sources of error and bias when assigning sex based on wing length. There was no evidence for a heritability of wing lengths that could result in localised populations of atypical size via a 'founder effect', which would otherwise undermine biometric sexing. Additionally, potentially misclassified birds did not differ from others in how long they persisted in the local population, so avoiding any potential bias of misclassification in demographic analyses. Compared to Marsh Tit data collected during intensive studies, the national data set pooled from contributors across Britain showed much greater variation in wing lengths, resulting from wider variation in the accuracy of measurement and recording. This variation in pooled data can have implications for analyses, and we discuss the importance of data quality in ringing schemes. [ABSTRACT FROM AUTHOR]

The European Union for Bird Ringing (EURING) coordinates bird ringing at a continental scale and operates the EURING Data Bank (EDB) to facilitate large-scale analyses of movements and demography. The EDB contains over 10 million individual encounter records which are summarised on a publicly available website, the EDB index. EURING welcomes applications to analyse these data. Ring-recovery data from the EDB contribute to research on many ecological issues, particularly migration and movements, hunting, mortality causes, disease transmission, population dynamics and dispersal. Recent developments will facilitate the incorporation of comprehensive sets of first-encounter records and local recaptures which are essential for robust quantitative studies of population dynamics and movements. Furthermore, the recent inclusion of fields for moult, measurements and weights within the EURING code will facilitate novel research at a European scale. We expect increasing use of the EDB for quantitative studies of avian demography and movements with high applied value. Wherever possible, this research should also incorporate complementary ecological information. EURING’s immediate priority is the production of a European Migration Atlas that would provide an up-to-date synthesis of the movements of European bird populations, with many direct implications for their conservation. [ABSTRACT FROM PUBLISHER]

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]

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.

The article focuses on the importance of the quantitative interpretation of the movement patterns of birds from ring recoveries. It notes that interpretation is important in establishing a conservation policy for migratory birds and in understanding the effect and the spread of disease. Among the statistical methods and tools used for the analysis include the drawing of lines, dots and kernels on a map to locate sites, and a compass diagram to describe the direction of travel.

The article reports on the European bird ringing schemes organization EURING which partnered with a web-based application to develop the mapping migration routes of waterfowl species which are identified with the highest potential to carry Highly Pathogenic Avian Influenza H5N1 across Europe. It states that the Constant Effort Site (CES) ringing demonstrated how the heavy rainfall during summer of 2007 had a negative effect on the breeding success and present recoveries of birds and their migration patterns and longevity records. It suggests that the total number of birds ringed was 7% lower than the mean of previous years due to the heavy rainfall that affects their breeding success.

Abstract: Mist netting is the most commonly used method for catching birds for scientific ringing, but despite decades of use, there have been few attempts to quantify the associated potential risks to the individuals caught. Any incidence of mortality through capture and handling, however low, is of potential ethical concern and may also introduce biases into the data. We estimate the mortality rate associated with capture of previously ringed (recaptured) passerines from the British and Irish Ringing Scheme (c. 1.5 million records) caught using mist nets. The importance of species, age, mass, month, time, previous captures, and an index of predator occurrence was tested using generalized linear mixed‐effects models. The average mortality rate was 0.0011, most of which was reported to occur before the individuals had been extracted from the nets (c. 70% of incidents). Juveniles appeared to be at higher risk and the incidence of predation from mist nets was seasonal, with increased risk during the winter. Species differed in their reported mortality rates with the apparent risk being greatest for Chiffchaff Phylloscopus collybita (0.0029) and Bullfinch Pyrrhula pyrrhula (0.0027). To improve our understanding (and hence minimize risk in future), we recommend collecting more complete data on incidences of mortality, and also injuries; exercising increased care when the species we have identified as being at greater risk are likely to be captured, and ensuring there are robust procedures for the checking of nets (as most reported incidents of mortality occur before handling). We also recommend that all Ringing Schemes should collate and make available data on capture‐related mortality. Overall rates of mortality associated with capture, although, were low and support the use of mist netting as a safe capture technique, without undue bias from mortality, when used by appropriately trained individuals. [ABSTRACT FROM AUTHOR]

Male-biased sex ratios occur in many bird species, particularly in those with small or declining populations, but the causes of these skews and their consequences for local population demography are rarely known. Within-species variation in sex ratios can help to identify the demographic and behavioural processes associated with such biases., Small populations may be more likely to have skewed sex ratios if sex differences in survival, recruitment or dispersal vary with local abundance. Analyses of species with highly variable local abundances can help to identify these mechanisms and the implications for spatial variation in demography. Many migratory bird species are currently undergoing rapid and severe declines in abundance in parts of their breeding ranges and thus have sufficient spatial variation in abundance to explore the extent of sex ratio biases, their causes and implications., Using national-scale bird ringing data for one such species (willow warbler, Phylloscopus trochilus), we show that sex ratios vary greatly across Britain and that male-biased sites are more frequent in areas of low abundance, which are now widespread across much of south and east England. These sex ratio biases are sufficient to impact local productivity, as the relative number of juveniles caught at survey sites declines significantly with increasing sex ratio skew., Sex differences in survival could influence this sex ratio variation, but we find little evidence for sex differences in survival increasing with sex ratio skew. In addition, sex ratios have become male-biased over the last two decades, but there are no such trends in adult survival rates for males or females. This suggests that lower female recruitment into low abundance sites is contributing to these skews., These findings suggest that male-biased sex ratios in small and declining populations can arise through local-scale sex differences in survival and dispersal, with females recruiting disproportionately into larger populations. Given the high level of spatial variation in population declines and abundance of many migratory bird species across Europe at present, male-biased small populations may be increasingly common. As singing males are the primary records used in surveys of these species, and as unpaired males often sing throughout the breeding season, local sex ratio biases could also be masking the true extent of these population declines. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the author discusses reviews on the importance of research techniques particularly ringing, papers on history of ringing in Great Britain and Ireland, and papers that discusses aspect of birds such a migration, population, and conservation.

Tracking devices are useful in studying the movement and behaviour of birds throughout the year. However, the effects of device attachment must be monitored for bird welfare and the scientific veracity of information gathered. We report on a trial of three different harness types (leg-loop, body and wing) for attaching GPS devices to Lesser Black-backed Gulls Larus fuscus and of a leg-loop harness on Great Skuas Stercorarius skua. This trial evaluated the functionality of the device whilst deployed, harness retention and the effects of each harness on the birds. The leg-loop harness prevented the devices from charging, due to feathers overlapping their solar panels, and individuals of both species shed this attachment during the first breeding season. For Lesser Black-backed Gull, devices functioned properly when attached using body and wing harnesses; foraging behaviour and territory attendance of birds were similar to the findings of other studies. Despite small sample sizes, annual adult survival rates for Lesser Black-backed Gull were similar to published estimates, suggesting harnesses had no deleterious effects. The wing harness has a smaller amount of skin contact than the body harness, and a non-constricting fit that better accommodates changes in body size. The wing harness was therefore considered the most appropriate for long-term studies. [ABSTRACT FROM AUTHOR]

Aim Recent, rapid population declines in many Afro-Palaearctic migratory bird species have focussed attention on changing conditions within Africa. However, processes influencing population change can operate throughout the annual cycle and throughout migratory ranges. Here, we explore the evidence for impacts of breeding and non-breeding conditions on population trends of British breeding birds of varying migratory status and wintering ecology. Location Great Britain (England & Scotland). Methods Within- and between-species variation in population trends is quantified for 46 bird species with differing migration strategies. Results Between 1994 and 2007, rates of population change in Scotland and England differed significantly for 19 resident and 15 long-distance migrant species, but were similar for 12 short-distance migrant species. Of the six long-distance migrant species that winter in the arid zone of Africa, five are increasing in abundance throughout Britain. In contrast, the seven species wintering in the humid zone of Africa are all declining in England, but five of these are increasing in Scotland. Consequently, populations of both arid and humid zone species are increasing significantly faster in Scotland than England, and only the English breeding populations of species wintering in the humid zone are declining. Main conclusions Population declines in long-distance migrants, especially those wintering in the humid zone, but not residents or short-distance migrants suggest an influence of non-breeding season conditions on population trends. However, the consistently less favourable population trends in England than Scotland of long-distance migrant and resident species strongly suggest that variation in the quality of breeding grounds is influencing recent population changes. The declines in humid zone species in England, but not Scotland, may result from poorer breeding conditions in England exacerbating the impacts of non-breeding conditions or the costs associated with a longer migration, while better conditions in Scotland may be buffering these impacts. [ABSTRACT FROM AUTHOR]

The bi-annual crossing of the Sahara desert is a considerable energetic challenge faced by approximately a quarter of Europe's total bird population, as they migrate to and from sub-Saharan non-breeding grounds. Where, when and how migratory birds prepare for the crossing remains to be defined in many species, especially in sub-Saharan Africa. Here, we describe the migration and fuelling strategies employed by the Grasshopper Warbler Locustella naevia during the northern autumn and spring to cross the western Sahara using ringing datasets from Portugal and Senegal. Body masses in recaptured birds combined with flight ranges suggest that <10% of birds in Portugal could have reached sub-Saharan Africa without refuelling. Estimated rates of mass change [up to 3.4% of lean body mass (LBM)/day] and stopover durations (mean 8 days) also suggest that the average bird in Portugal required further stopovers, and point to the strategic importance of northwest Africa during autumn migration. In sub-Saharan Africa, Grasshopper Warblers began to leave Senegal as early as mid-January in order to spend up to 2 months at unknown sites in North Africa. Fuelling for the northward journey across the Sahara was characterised by a slow fuelling rate (1% LBM/day) and long duration relative to Portugal (19 days). The constraining factor on fuelling rates in Senegal is hypothesised to be low resource availability associated with the Sahelian dry season. These resources appear to vary annually with Sahelian rainfall, resulting in variable fuel loads and fuelling rates and potentially leading to fuelling shortfalls in years of low rainfall. [ABSTRACT FROM AUTHOR]

Aim Over the past three decades, evidence has been growing that many Afro-Palaearctic migratory bird populations have suffered sustained and severe declines. As causes of these declines exist across both the breeding and non-breeding season, identifying potential drivers of population change is complex. In order to explore the roles of changes in regional and local environmental conditions on population change, we examine spatial and temporal variation in population trajectories of one of Europe’s most abundant Afro-Palaearctic summer migrants, the willow warbler, Phylloscopus trochilus. Location Britain and Ireland. Methods We use national survey data from Britain and Ireland (BBS: BTO/RSPB/JNCC Breeding Bird Survey and CBS: BWI/NPWS/Heritage Council Countryside Breeding Survey) from 1994 to 2006 to model the spatial and temporal variation in willow warbler population trends. Results Across Britain and Ireland, population trends follow a gradient from sharp declines in the south and east of England to shallow declines and/or slight increases in parts of north and west England, across Scotland and Ireland. Decreasing the spatial scale of analysis reveals variation in both the rate and spatial extent of population change within central England and the majority of Scotland. The rates of population change also vary temporally; declines in the south of England are shallower now than at the start of the time series, whereas populations further north in Britain have undergone periods of increase and decline. Main conclusion These patterns suggest that regional-scale drivers, such as changing climatic conditions, and local-scale processes, such as habitat change, are interacting to produce spatially variable population trends. We discuss the potential mechanisms underlying these interactions and the challenges in addressing such changes at scales relevant to migratory species. [ABSTRACT FROM AUTHOR]

The article presents a study which identifies some of the key opportunities and challenges that must be prioritized by large-scale bird-making programmes in the next 10 to 20 years in the British and Irish Ringing Scheme. It mentions various issues such as the global environmental change and disease control. It also states that the technologies for bird studies have capabilities to facilitate study designs that require fewer birds to be marked, and provides rapid collation, sharing, and analysis.

In theory, survival rates and consequent population status might be predictable from instantaneous behavioural measures of how animals prioritize foraging vs. avoiding predation. We show, for the 30 most common small bird species ringed in the UK, that one quarter respond to higher predation risk as if it is mass-dependent and lose mass. Half respond to predation risk as if it only interrupts their foraging and gain mass thus avoiding consequent increased starvation risk from reduced foraging time. These mass responses to higher predation risk are correlated with population and conservation status both within and between species (and independently of foraging habitat, foraging guild, sociality index and size) over the last 30 years in Britain, with mass loss being associated with declining populations and mass gain with increasing populations. If individuals show an interrupted foraging response to higher predation risk, they are likely to be experiencing a high quality foraging environment that should lead to higher survival. Whereas individuals that show a mass-dependent foraging response are likely to be in lower quality foraging environments, leading to relatively lower survival. [ABSTRACT FROM AUTHOR]

Wildlife conservation policies directed at common and widespread, but declining, species are difficult to design and implement effectively, as multiple environmental changes are likely to contribute to population declines. Conservation actions ultimately aim to influence demographic rates, but targeting actions towards feasible improvements in these is challenging in widespread species with ranges that encompass a wide range of environmental conditions. Across Europe, sharp declines in the abundance of migratory landbirds have driven international calls for action, but actions that could feasibly contribute to population recovery have yet to be identified. Targeted actions to improve conditions on poor-quality sites could be an effective approach, but only if local conditions consistently influence local demography and hence population trends. Using long-term measures of abundance and demography of breeding birds at survey sites across Europe, we show that co-occurring species with differing migration behaviours have similar directions of local population trends and magnitudes of productivity, but not survival rates. Targeted actions to boost local productivity within Europe, alongside large-scale (non-targeted) environmental protection across non-breeding ranges, could therefore help address the urgent need to halt migrant landbird declines. Such demographic routes to recovery are likely to be increasingly needed to address global wildlife declines. [ABSTRACT FROM AUTHOR]

TYERS, G.F.O., et al.: Coronary Sinus Lead Extraction.Complications are reported more frequently with the implantation of coronary sinus (CS) than other types of leads, and attempts to extract CS leads may also be associated with increased risks. The authors have performed nonthoracotomy lead extraction (LE) since 1981 and maintained a detailed database. By November 2001, 796 leads had been removed from 401 patients. We undertook review of our CS-LE experience to evaluate prevalence, safety, and efficacy. Of 14 patients referred for CS-LE, 7 were treated in the last year. In six the lead had been placed in the CS intentionally, and in eight inadvertently. One recent patient treated with biventricular pacing was septic and died before LE was undertaken. In nine men and four women (mean age 66 years) had one each CS lead and a total of 34 LEs (2.6/patient). Four CS leads had been in place for <6 months (mean 1.5 month), whereas nine had been in place for between 6 months and 27 years. Several LE methods were used, from simple traction to the use of intraluminal locking stylets and powered sheaths. Complete removal of all leads was achieved in all patients. CS-LE required a mean of 13 minutes, including 1.8 minutes of fluoroscopy. There were no serious complications during the procedures, and the mean hospital stay was 4 days. (PACE 2003; 26[Pt. II]:524–526). [ABSTRACT FROM AUTHOR]

Bird ringing was established more than a century ago to gather information on bird movements. Since then, ornithologists have systematically collected huge databases of records of birds ringed and subsequently re-encountered, but, to date, there have been few quantitative attempts to identify migratory routes from ringing data. Here, we develop a novel, quantitative method for describing migration routes using ringing data and we applied it to a dataset of 72,827 ring recoveries of the Barn Swallow (Hirundo rustica) through western and central Europe from the EURING and SAFRING databanks spanning 1908-2011. We considered movements of 332 individuals during spring migration and 1509 during autumn migration. The results indicate that, in spring, Barn Swallows enter western Europe through Gibraltar or by crossing the Mediterranean Sea through the Balearic Islands, Sardinia, and the Italian peninsula. They then spread over a wide front. In northern France, Belgium and the Netherlands routes diverge, pointing toward either the British Isles or Denmark and Scandinavia. Autumn migration routes are similar to those in spring. The general migration pattern that emerged from the analyses was consistent with previous descriptions of migratory movements of this well-known species. However, this analysis also revealed some previously undocumented migration patterns. For instance, in spring, some migrants moved from the Balearic Islands to Corsica and Italy, thus making a rather long eastward crossing of the Mediterranean Sea. In autumn, some migrants moved from the Balkan Peninsula westwards toward Italy. Analyses restricted to recoveries within the same spring or the same autumn and to birds found dead showed similar patterns. Our procedure was, therefore, able to identify migration patterns over a large geographical area, and may be extended to those species for which large datasets of ring recoveries or sight-resight data are available. [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]

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]

Across Europe, rapid population declines are ongoing in many Afro-Palaearctic migratory bird species, but the development of appropriate conservation actions across such large migratory ranges is severely constrained by lack of understanding of the demographic drivers of these declines. By constructing regional integrated population models (IPMs) for one of the suite of migratory species that is declining in the southeast of Britain but increasing in the northwest, we showthat, while annual population growth rates in both regions vary with adult survival, the divergent regional trajectories are primarily a consequence of differences in productivity. Between 1994 and 2012, annual survival and productivity rates ranged over similar levels in both regions, but high productivity rates were rarer in the declining southeast population and never coincided with high survival rates. By contrast, population growth in the northwest was fuelled by several years in which higher productivity coincided with high survival rates. Simulated population trajectories suggest that realistic improvements in productivity could have reversed the decline (i.e. recovery of the population index to more than or equal to 1) in the southeast. Consequently, actions to improve productivity on European breeding grounds are likely to be a more fruitful and achievable means of reversing migrant declines than actions to improve survival on breeding, passage or sub-Saharan wintering grounds. [ABSTRACT FROM AUTHOR]

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]

Migration is a fundamental stage in the life history of several taxa, including birds, and is under strong selective pressure. At present, the only data that may allow for both an assessment of patterns of bird migration and for retrospective analyses of changes in migration timing are the databases of ring recoveries. We used ring recoveries of the Barn Swallow Hirundo rustica collected from 1908–2008 in Europe to model the calendar date at which a given proportion of birds is expected to have reached a given geographical area (‘progression of migration’) and to investigate the change in timing of migration over the same areas between three time periods (1908–1969, 1970–1990, 1991–2008). The analyses were conducted using binomial conditional autoregressive (CAR) mixed models. We first concentrated on data from the British Isles and then expanded the models to western Europe and north Africa. We produced maps of the progression of migration that disclosed local patterns of migration consistent with those obtained from the analyses of the movements of ringed individuals. Timing of migration estimated from our model is consistent with data on migration phenology of the Barn Swallow available in the literature, but in some cases it is later than that estimated by data collected at ringing stations, which, however, may not be representative of migration phenology over large geographical areas. The comparison of median migration date estimated over the same geographical area among time periods showed no significant advancement of spring migration over the whole of Europe, but a significant advancement of autumn migration in southern Europe. Our modelling approach can be generalized to any records of ringing date and locality of individuals including those which have not been recovered subsequently, as well as to geo-referenced databases of sightings of migratory individuals. [ABSTRACT FROM AUTHOR]

Each May, red knots (Calidris canutus rufa) congregate in Delaware Bay during their northward migration to feed on horseshoe crab eggs (Limulus polyphemus) and refuel for breeding in the Arctic. During the 1990s, the Delaware Bay harvest of horseshoe crabs for bait increased 10-fold, leading to a more than 90% decline in the availability of their eggs for knots. The proportion of knots achieving weights of more than 180 grams by 26-28 May, their main departure period, dropped from 0.6-0.8 to 0. 14-0.4 over 1997-2007. During the same period, the red knot population stopping in Delaware Bay declined by more than 75%, in part because the annual survival rate of adult knots wintering in Tierra del Fuego declined. Despite restrictions, the 2007 horseshoe crab harvest was still greater than the 1990 harvest, and no recovery of knots was detectable. We propose an adaptive management strategy with recovery goals and annual monitoring that, if adopted, will both allow red knot and horseshoe crab populations to recover and permit a sustainable harvest of horseshoe crabs. [ABSTRACT FROM AUTHOR]

1. Millions of shorebirds migrate each year through a small number of highly productive staging areas where they often conflict with fisheries interests. Delaware Bay, USA, is a major shorebird stopover site where, in spring, many thousands of shorebirds undergo rapid mass gain by feeding on the eggs of commercially harvested horseshoe crabs Limulus polyphemus. 2. Environmental factors may cause deviations from the best migration schedule. We used within-year mass gain data from red knot Calidris canutus caught in Delaware Bay between 1998 and 2005 to determine the degree of flexibility individuals have to vary migration speed. 3. Mass gain by birds below 133 g was shown to comprise 15·3% fat (39 kJ g−1), the remainder being lean mass (6 kJ g−1). Above this critical level, fat comprised 83·9% of mass deposition. The rates of energy deposition (kJ d−1) were therefore fundamentally different between the two states but were among the highest ever recorded among vertebrates (5–7 × basic metabolic rate). 4. A total of 36–62% of the variation in observed rates of energy deposition between 1998 and 2002 was explained by a year factor, date and mass at initial capture and interaction terms, such that light-weight birds at the end of May had rates of mass gain or energy deposition two to three times higher than birds of similar mass in mid-May, indicating that birds were attempting to achieve a certain mass by a certain date. In 2003 and 2005, this relationship broke down as a result of lower densities of eggs. 5. Synthesis and application. The maintenance of high densities of crab eggs required for high rates of mass gain in red knot requires severe cuts in, or the complete cessation of, the crab harvest, reduced human and raptor-related disturbance as well as management of beaches to provide sufficient crab-spawning habitat. These findings are widely applicable to other systems where harvesting activities come into conflict with migrating animals and show that certain sections of the population, in this case the long-distance migrants from South America, will be impacted more than short-distance migrants whose physiology may give them access to alternative food resources. [ABSTRACT FROM AUTHOR]

The Wash, in eastern England, supports internationally important populations of 11 species of shorebird. A major commercial shellfishery provides potential conflict between fishermen and nature conservation interests. During the 1990s, high fishing mortality and low recruitment substantially reduced the stocks of cockle (Cerastoderma edule) and mussel (Mytilus edulis). Population models, constructed from estimates of survival and recruitment, indicated that declines in the availability of cockles and mussels were associated with changes in oystercatcher (Haemotopus ostralegus) survival between 1970 and 1998, including three periods of mass mortality, and also the recruitment of juvenile birds to both oystercatcher and knot (Calidris canutus) populations. Emigration of knot may also have taken place. Cockle recruitment was dependent on climatic conditions, whereas mussel populations tended to be stable. The decline in mussel stocks, due to over-fishing, increased the vulnerability of the oystercatcher population to mass-mortality episodes in poor cockle years. The key to preventing major oystercatcher kills in future is to ensure sufficient mussels are available in poor cockle years. Recent cultivation of mussels in inter-tidal areas has been beneficial and is an important management tool for maintaining bird populations. [Copyright &y& Elsevier]

In this study, we investigated whether birds could be vectors facilitating long‐distance spread of Phytophthora ramorum in Britain. Migratory bird species associated with the main sporangium‐producing host plants and most likely to pick up P. ramorum spores were considered. Swabs were taken from the flank and “feet” of 1,014 birds over a 12‐month period (April 2011–March 2012) in the west of Britain and subsequently analyzed for the presence of P. ramorum using nested PCR. Ten positive samples from 10 birds were identified: three in Cornwall, one in Devon, three in Gloucestershire, two in north Wales and one in Merseyside. Phytophthora ramorum was detected on samples from four species of thrushes (Redwing Turdus iliacus, Fieldfare T. pilaris, Blackbird T. merula and Song Thrush T. philomelos) and one species of warbler (Chiffchaff Phylloscopus collybita). All birds that tested positive were sampled in late autumn and winter (October–February), when long‐distance movements (over 100 km) would have stopped. The low incidence of P. ramorum found using PCR suggests that the incidence of inoculum, whether viable or not, on birds was low. The apparently low incidence of inoculum on birds suggests migratory passerine birds can carry P. ramorum inoculum on their feathers and “feet,” albeit at low frequency. The dates of positive samples indicate that birds would not have been moving long distances at the time but further work is needed to estimate the extent of their contribution to the spread of P. ramorum in Britain. [ABSTRACT FROM AUTHOR]

All ecological measurements are subject to error; the effects of missed detection (false negatives) are well known, but the effects of mistaken detection (false positives) are less understood. Long-term capture–recapture datasets provide valuable ecological insights and baselines for conservation and management, but where such studies rely on noninvasive re-encounters, such as field-readable color bands, there is the potential to accumulate detection errors as the length of the study and number of tags deployed increases. We investigated the prevalence and effects of misreads in a 10-yr dataset of Red Knots (Calidris canutus rufa) marked with field-readable leg flags in Delaware, USA. We quantified the effects of misreads on survival estimation via a simulation study and evaluated whether removal of individuals only reported once in a year (potential misreads) influenced survival estimation from both simulated datasets and our case study data. We found overall apparent error rates of 0.31% (minimum) to 6.6% (maximum). Observer-specific error rates and the variation among observers both decreased with the number of flags an observer recorded. Our simulation study showed that misreads lead to spurious negative trends in survival over time, particularly for long-term studies. Removing all records in which a flag was only recorded once in a sampling occasion reduced bias and eliminated spurious negative trends in survival but also reduced precision in survival estimates. Without data filtering, we found a slight decrease in Red Knot annual survival probability from 2008 to 2018 (β = −0.043 ± 0.03), but removing all single-observation records resulted in no apparent trend (β = −0.0074 ± 0.02). Spurious trends in demographic rates could influence inference about population trajectories and resultant conservation decision-making. Data filtering could eliminate errors, but researchers should carefully consider the tradeoff between precision obtained by larger sample sizes and potential bias due to misreads in their data. [ABSTRACT FROM AUTHOR]