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Over 600 bird atlases projects have been implemented across 93 countries, with at least 380,000 participants. Bird atlases with larger geographical scope had greater research impact but those utilizing online data submission and so higher number of participants had lower research impact. To provide a comprehensive global review of bird atlases, to explore the impact of bird atlases in research, and identify variables that influence impact. A database of bird atlases was compiled. Variables were extracted including: overall survey effort (an index generated using principal components analysis (PCA) comprised of total survey area, number of participants, and number of data records); research impact (an index generated using PCA comprised of bibliometric measures extracted from Scopus and Google Scholar); geographical details; fieldwork, project, and publication timing; fieldwork methods. We then used mixed linear models to explore how these variables differed across atlases, and which were predictors of research impact index. As of 2021, over 600 bird atlases projects have been implemented across 93 countries, with at least 380,000 participants worldwide. Total survey area, geopolitical scale, and number of atlas generations had significant positive relationships with research impact. Negative relationships were found between research impact and whether an atlas was published in English and the use of online data submission platforms like eBird. However, we found a significantly positive relationship between atlases using online data submission and our measure of survey effort. Bird atlases have been undertaken all around the world at a wide variety of geopolitical scales, and are likely to be influential through widespread impact on knowledge, including research impact and citizen science involvement. Atlases utilizing online data submission generate more data and have a higher level of participant engagement but are less frequently cited by researchers in both scientific and grey literature. [ABSTRACT FROM AUTHOR]

Copyright of Ostrich: The Journal of African Ornithology is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Capsule: There is a substantial gain in precision and accuracy of geolocator locations when using a light stalk. Aims: Light stalks or tubes increase the accuracy of geolocators when tracking migrant birds because they reduce potential shading of the light sensor by feathers but may increase detrimental tag effects. We aimed to determine how adding light stalks to geolocator tags increased accuracy and precision of locations. Methods: We quantified how precision and accuracy of geolocator locations was affected by comparing variation of sunrise and sunset times from tags with variable length light stalks (6 of 0 mm, 8 of 5 mm and 21 of 10 mm). Tags were fitted to Whinchats Saxicola rubetra in central Nigeria (the known location to compare accuracy), and variance in latitude and longitude of geolocator estimated locations were also compared across light stalk lengths during spring migration stationary locations, and at breeding sites in Eastern Europe, for both Geolight and FlightR methods. Results: Without a light stalk, the standard deviation of sunset and sunrise times increased by 50% and 100%, respectively (i.e. less precise): confidence intervals for latitude were larger by about 4.3 degrees at non-breeding low latitudes and 1.8 degrees at stop-over latitudes, or confidence intervals for longitude were larger by 2.3 degrees, dependent on analysis method. Estimated sun elevation angles were significantly less accurate and so calculated non-breeding locations were significantly less accurate by about 8 degrees of latitude. Precision in sunrise, sunset times, latitude and longitude, was similar when using a 5 mm or 10 mm stalk. Conclusions: The results show a substantial gain in precision and accuracy of low latitude geolocator locations when using a light stalk that brings the sensor above covering feathers. There is no advantage from longer light stalk lengths than those necessary to just expose the light sensor above the feathers, at least for small passerines. [ABSTRACT FROM AUTHOR]

West Africa has high bird diversity and is a crucial non-breeding area for over one-third of European breeding species, yet local capacity for ornithological research and so targeted bird conservation is perceived to be limited. I reviewed all the published literature on the Web of Science™ classified as ‘ornithology’ with an accompanying keyword of a country’s name, over the last three decades, from the 16 countries within West Africa and compared it with that from 16 Western European countries. Inclusion of the country’s name as a search term identified any papers produced by local authors, and so should provide an index of local ornithological capacity. Overall only 129 papers were produced from 1987 to 2016 with West African authors (range: zero Burkina Faso to 45 Nigeria), significantly fewer compared with 12 380 with European authors (range: 71 Greece to 2 745 England). The number of papers produced increased significantly at similar rates over the three-decade period in both continents. The number of papers produced by local authors in West Africa and Europe approximately doubled each decade, but variation between countries was large, particularly in West Africa. The results are broadly the same when paper output is adjusted for the population of each country. Of the three West African countries that showed a consistent increase in numbers of locally authored ornithological papers, only Nigeria showed a highly significant increase and this increase was down to a single ornithological research institute established there in 2002. The results confirm that there is little local ornithological capacity in West Africa and this is not changing except in Nigeria, where even a single new research institute can make a significant difference because of the very low baseline. [ABSTRACT FROM AUTHOR]

Copyright of Ostrich: The Journal of African Ornithology is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Wintering Northern WheatearsOenanthe oenanthein the Sahel region of Northern Nigeria held small (approximately 70 m diameter) distinct territories during the study period, and territory size did not differ between adult and first winter birds. Evidence suggests that Wheatears may maintain small territories for a significant duration of the winter, similar to many other migrants. [ABSTRACT FROM AUTHOR]

Unprecedented rates of deforestation on tropical islands are threatening high numbers of endemic species, and empirical evidence is needed to better understand the implications of changes in land-use on biodiversity and to guide conservation actions. We assessed the effects of changes in land-use on the lowland avifauna of the tropical island of Makira in the Solomon Islands. We examined species richness and community assemblages, with a particular focus on endemism and functional traits, to provide further insight into the conservation value of the dominant types of land-use on Makira (i.e. intact forest, secondary forest, food gardens, mixed Cocoa plantations, and monoculture Cocoa plantations). We found species richness was similar across habitats, but endemic-species richness decreased as intensity of land-use increased. There were significant differences in the occurrence of functional groups between habitats. Fifteen of the 42 species observed showed significant variation in abundance across habitats. Of those species that varied, 12 were endemic to Makira or to Melanesia, with seven of these endemics being absent from the monoculture Cocoa plantations. As tropical islands have less functional redundancy than continental land masses, protecting the remaining forest and improving habitat connectivity will be even more critical for conserving their endemic species and maintaining ecosystem functioning. [ABSTRACT FROM AUTHOR]

Occurrence of animals in an area and the size of territories they occupy is a function of resource availability and the environmental conditions in that area. Territory location in birds is often determined by availability of nesting habitat and we investigate whether this is the case for the little-studied Northern Anteater-chatMyrmecocichla aethiops. Territory size and location were mapped over two months in 2012 at 25 different sites where the birds occurred in central Nigeria and compared to 25 random sites where they did not, 500 m away. Vegetation variables, invertebrate abundance indicators, anthropogenic variables (availability of nest sites) and bird community components were measured and compared with adjoining areas (500 m away) from which the birds were absent in order to determine important factors determining territory location and size. Territories were 1.23 ha (SE 0.14) in size and were widely separated and so non-contiguous. Increasing numbers of abandoned wells, ant nests and termite mounds increased the probability of territory occupation. Territory size increased with the number of anteater-chats but decreased with increasing number of ant nests and overall bird diversity that were probably proxies for habitat quality. Overall, choice of preferred areas for the Northern Anteater-chat was centred on nesting sites and then habitat quality and group size probably determined territory size. [ABSTRACT FROM PUBLISHER]

CapsuleThe reproductive rate of Rose-ringed Parakeets in the UK was higher in 2001-2003 than previously estimated. AimTo measure reproductive rate and the factors affecting this in Rose-ringed Parakeets in England during a period of rapid expansion in population of this potential invasive species. MethodsDuring 2001–2003, 108 nests were located and monitored in southwest London, southeast London and the Isle of Thanet. Nest survival using the Mayfield method, fledging success and the characteristics of the nest and surrounding vegetation were measured. ResultsThe mean date of first egg was 26 March ± 1.3 days and the median clutch size was 4 eggs. Mayfield nest survival rate was 72%. Reproductive success was 1.4 ± 0.3 young fledged per nest. Parakeets bred predominantly in ash (Fraxinus) and oak (Quercus). Nest trees had a diameter at breast height (DBH) of 73.7 ± 4.7 cm (mean ± se). ConclusionReproductive success in this parakeet was higher than previously estimated (0.8 young fledged per nest prior to 1999). This reproductive output is sufficient to explain the rapid increase in Rose-ringed Parakeet numbers (from an estimated 1500 birds in 1996 to nearly 10,000 birds by 2004) if Rose-ringed Parakeets have a low death rate similar to other parrots. [ABSTRACT FROM AUTHOR]

Diurnal patterns of body mass gain in small temperate birds are of theoretical interest because they are largely a consequence of the starvation vs predation risk trade-off. In tropical birds, diurnal variation in body mass may also be influenced by other constraints such as water availability, digestive bottlenecks and the avoidance of periods of high temperature. We recorded body mass and amount of seed eaten with time of day and temperature in three small granivorous species, feeding on baited balances in a savanna habitat in tropical West Africa. Birds fed in the morning and afternoon but almost never visited balances to feed during the middle of the day. Body mass increased with time of day, but with a clear bimodal pattern so that mass was gained in the early morning and was then lost again by the time birds resumed feeding in the afternoon. Mass was then mostly regained at the end of the afternoon. There was a significant, but biologically small, increase in body mass with increasing temperature. When controlling for the effects of time of day, species, year and day, body mass on average increased to a peak at about 24 °C before declining slightly; daily temperature peaked at 27 °C during the midday period when the birds did not feed, and so mass was lost. Body mass gain between consecutive diurnal hours was greatest when the temperature was about 18 °C, during early morning feeding. Gain in body mass decreased as temperature increased by late morning, and stopped or even slightly decreased above 24 °C when birds stopped feeding. The amount of food eaten per visit to the balance was independent of time of day and temperature, confirming that the birds were regulating their mass adaptively, rather than simply reflecting availability of food. Body mass gain was not restricted to the early morning as expected with low predation risk and high starvation risk, nor was it restricted to just late in the day as expected with high predation risk and low starvation risk. Instead, high temperatures around midday may result in a period where foraging is avoided completely for energetic or water conservation reasons, driving the bimodal diurnal pattern of body mass gain. [ABSTRACT FROM AUTHOR]

Despite widespread interest in life histories and the comparison of parameters between tropical and temperate regions, there are still relatively few multispecies studies assessing annual survival in Afrotropical species. We used data from systematic mist-netting of savanna birds in Nigeria, between 2001 and 2008, to estimate survival for 40 Afrotropical bird species. Best-supported models were those incorporating constant survival (27 of 40) or the effects of transience (13 of 40). Survival ranged from 0.269 to 0.948 (mean ± SE = 0.64 ± 0.02), varied within and between families, and showed a positive relationship with mass in passerines. Survival was highest in the insectivorous Malaconotidae (0.79 ± 0.13) and lowest in the granivorous Estrildinae (0.51 ± 0.04). This pattern was also evident in a comparison of survival between guilds (highest in insectivores and lowest in granivores) suggesting that these species encounter seasonal starvation risks or exhibit a seasonal response to water availability, i.e. emigration from the study area leading to reduced site fidelity and lower apparent survival. Our estimates of adult survival are higher than those previously obtained from this site, comparable with those from other Afrotropical studies (i.e. >0.60) and higher than those from temperate zones (0.53 ± 0.01,n= 79). [ABSTRACT FROM AUTHOR]

Declines in populations of Palearctic migrants wintering in the Sahel of Africa have been linked to the impacts of climate change and habitat degradation in the region. Despite this, there is an almost complete lack of data on the density and distribution of Palearctic migrants wintering in the Sahel and whether they have the same habitat requirements as similar, resident Afrotropical species. We measured the density of five species of Palearctic warblers (Sylviidae) and 10 species of Afrotropical gleaning passerines (Sylviidae, Nectariniidae, Malaconotidae and Ploceidae) at 16 sites in the Sahel of northern Nigeria between October and April during two winters. Two species of Afrotropical gleaner (Hippolais pallida and Ploceus luteolus) showed seasonal variation in abundance, but this variation was unlikely to have decreased Afrotropical densities sufficiently to change the degree of competition experienced by Palearctic migrants. This observation, combined with a positive correlation between abundances of Afrotropical and Palearctic species, suggests that these two groups occur together and have similar spatial and temporal habitat requirements, and therefore possibly similar responses to habitat degradation. Sylvia communis appears to be the principal species utilising the region during spring migration, presumably for fattening prior to the trans-Saharan crossing, and is thus perhaps the most vulnerable species to habitat loss in the region. [ABSTRACT FROM AUTHOR]

Capsule Two widespread censuses of already degraded woodland in the Sahel in Northern Nigeria separated by five years (2002 and 2007) showed relatively small further changes in tree and bird density. Aims To determine how change in tree density affects African and Palearctic migrant bird density in already degraded Sahelian woodland. Methods We compared differences in the number of bird species and their abundance with differences in the size and number of woody plants between two seasons separated by five years at 16 degraded woodland sites across 250 km east-west in northern Nigeria. Results Densities of large trees (>5 m) decreased, but densities of smaller trees and shrubs increased, partly as a consequence of growth and because larger trees have been preferentially removed or partly cut down; tree densities were, however, initially low. Of 37 common bird species, 16% had higher densities and 22% had lower densities, in the second study period. The density of Common Whitethroats, Northern Wheatears and Yellow Wagtails was correlated with the number and size of trees, but not that of Lesser Whitethroat and Subalpine Warbler. Overall there was relatively little turnover in species between the two surveys and if (the initially low) tree density was halved, only approximately 2.1% of the average total for number of bird species per 0.2 ha point would be lost. Conclusion Few large changes in bird species' density were found, possibly because: (1) all habitats sampled were already at relatively low tree density - initial reductions from high tree density or near removal of all trees may cause larger changes in local bird densities; (2) reduction in the number of large trees was partially compensated by a more lush development of the vegetation as a whole in the second study period; and (3) the bird species remaining in degraded Sahelian woodland in northern Nigeria are already well adapted to habitat change and low tree density. [ABSTRACT FROM AUTHOR]

The article focuses on the assessment of avian's body condition through body mass and fat reserve data from population dynamics studies. It notes that mass and fat reserves may imply the index of condition and survival probability and fitness of birds on their corresponding environment. Moreover, it cites the importance of ecological determinants and birds' physiology such as habitat quality, migration, moulting and reproduction as factors contributing to the mass and energy utilization.

We describe the density, breeding and foraging ecology of the Berthelot's Pipit (Anthus berthelotii), an endemic passerine to the Atlantic islands, in the semi-arid coastal scrub of Tenerife. Furthermore, we analyse the effects of temperature and rainfall in the onset of reproduction and the behaviour (nest site and foraging site selection). The average density of the Pipit (using DISTANCE methodology) in the semi-arid coastal scrub was 7.1 birds 10ha-1, and the overall density estimate in grassland was 3.3 birds 10ha-1. The Pipit bred early (mean average first-egg laying date 12 February) and in response to rainfall (but not temperature). By the Mayfield method, the probability of the nests surviving the egg stage was 0.77 and of and the nests surviving the chick stage 0.67 - assuming an incubation period of 13 days and a chick stage of 12.5 days - based on the European average for the similar-sized Meadow Pipit Anthus pratensis. Overall nest survival pooling stages were 0.51. The Pipits had a low clutch size (3.3 eggs, range of 2-4). Nest damage by heavy rainstorms was the major cause of nest failures (three out of five failures). The Pipits nested preferentially in grass with relatively low densities of Euphorbia balsamifera bushes. Birds selected grassy areas as their main foraging site but also preferred to forage on large rocks during nesting: caterpillars were the main food items (14 out of 17 prey captures). [ABSTRACT FROM AUTHOR]

Areas experiencing a seasonal influx of migrants may be expected to have a high potential for competition between resident and migrant populations. Described differences in foraging behaviour and microhabitat selection between Palaearctic and Afrotropical species have been ascribed to competition between these groups. The first step in the assessment of whether there are any interspecific competitive interactions must be the identification of species with the greatest overlap in habitat selection and foraging method. Our results provide a tool for identifying species with the greatest potential for interspecific competition. These species should be the focus of any further examination of competition within the Sahel. [ABSTRACT FROM AUTHOR]

No one bird survey technique is perfect. Either the assumptions made by a technique are difficult to meet in the field, or there are biases due to the observer, the birds themselves, the landscape, or the nature of the habitat. These include survey effort, time of day, time of year, edge effects, vegetation structure, and variation in detectability functions. Biases in methodologies are only a problem if they are systematic with respect to the variables that are being tested. If, however, biases are randomly distributed with respect to the variables under consideration, they cannot affect a positive result, although a negative result may occur because of the noise they may introduce into the analysis. Therefore, it is crucial to determine and minimise biases in any study. We use extensive line transect census data from a study of the effects of habitat fragmentation on forest birds in Nigeria to illustrate the range of possible biases and their effects, and then how these may be accounted for. Asymptote analysis showed that, although more bird species were recorded in larger fragments because transects in those fragments were longer, this bias had little overall effect as long as transects were longer than a few hundred meters. The number of bird species declined significantly and substantially between 07:00 and 11:00. The effects of edge on number of species was only significant for the first 200m from the edge. Vegetation variables did not vary significantly across sites, suggesting that variation in overall detectability could be ignored, but there was considerable variation in the detectability functions of different species. We recommend the following procedures for surveys of West African rain forests: a minimum transect length of 1 600m; sub-division of transects into shorter sections (100m-200m) along with vegetation measurements for each section to allow for the assessment of the effects of habitat variation; transects to start at least 200m from the edge of the forest; the use of species-specific detectability functions if they are to be used at all; and for all transects to reach their mid-point at the same time each day, preferably early in the morning. [ABSTRACT FROM AUTHOR]

Moult timing and duration was estimated in 17 passerine bird species in the guinea savanna zone of Nigeria. In 15 species, moult duration was much longer than in the equivalent north temperate resident passerines. Sixteen species were found to moult seasonally, with most granivorous species moulting in the dry season. General seasonal patterns of either insectivores or nectarivores were not apparent. These results are discussed in the context of other important aspects of the annual cycle and the life history styles of tropical birds. [ABSTRACT FROM AUTHOR]

The article reports on the habitat selection and population size of the Fuerteventura Blue Tit (Parus caeruleus degener). The Blue Tit is a common passerine that ranges over the western Palearctic, with 16 subspecies. P. c. degener has a very restricted range and is also the only Canarian subspecies included in the regional catalogue of threatened taxa as sensitive to habitat alteration.