Spring Migration Of Birds Research Articles

Determinants of spring migration departure dates in a New World sparrow: Weather variables reign supreme.

Numerous factors influence the timing of spring migration in birds, yet the relative importance of intrinsic and extrinsic variables on migration initiation remains unclear. To test for interactions among weather, migration distance, parasitism, and physiology in determining spring departure date, we used the Dark-eyed Junco (Junco hyemalis) as a model migratory species known to harbor diverse and common haemosporidian parasites. Prior to spring migration departure from their wintering grounds in Indiana, USA, we quantified the intrinsic variables of fat, body condition (i.e., mass ~ tarsus residuals), physiological stress (i.e., ratio of heterophils to lymphocytes), cellular immunity (i.e., leukocyte composition and total count), migration distance (i.e., distance to the breeding grounds) using stable isotopes of hydrogen from feathers, and haemosporidian parasite intensity. We then attached nanotags to determine the timing of spring migration departure date using the Motus Wildlife Tracking System. We used additive Cox proportional hazard mixed models to test how risk of spring migratory departure was predicted by the combined intrinsic measures, along with meteorological predictors on the evening of departure (i.e., average wind speed and direction, relative humidity, and temperature). Model comparisons found that the best predictor of spring departure date was average nightly wind direction and a principal component combining relative humidity and temperature. Juncos were more likely to depart for spring migration on nights with largely southwestern winds and on warmer and drier evenings (relative to cooler and more humid evenings). Our results indicate that weather conditions at take-off are more critical to departure decisions than the measured physiological and parasitism variables.

Hyalomma rufipes on an untraveled horse: Is this the first evidence of Hyalomma nymphs successfully moulting in the United Kingdom?

During September 2018, a tick was submitted to Public Health England’s Tick Surveillance Scheme for identification. The tick was sent from a veterinarian who removed it from a horse in Dorset, England, with no history of overseas travel. The tick was identified as a male Hyalomma rufipes using morphological and molecular methods and then tested for a range of tick-borne pathogens including; Alkhurma virus, Anaplasma, Babesia, Bhanja virus, Crimean-Congo Haemorrhagic fever virus, Rickettsia and Theileria. The tick tested positive for Rickettsia aeschlimannii, a spotted fever group rickettsia linked to a number of human cases in Africa and Europe. This is the first time H. rufipes has been reported in the United Kingdom (UK), and the lack of travel by the horse (or any in-contact horses) suggests that this could also be the first evidence of successful moulting of a Hyalomma nymph in the UK. It is postulated that the tick was imported into the UK on a migratory bird as an engorged nymph which was able to complete its moult to the adult stage and find a host. This highlights that passive tick surveillance remains an important method for the detection of unusual species that may present a threat to public health in the UK. Horses are important hosts of Hyalomma sp. adults in their native range, therefore, further surveillance studies should be conducted to check horses for ticks in the months following spring bird migration; when imported nymphs may have had time to drop off their avian host and moult to adults. The potential human and animal health risks of such events occurring more regularly are discussed.

Meteorological factors affecting the risk of transmission of HPAI in Miyazaki, Japan

Highly pathogenic avian influenza (HPAI) outbreaks engender a severe economic impact on the poultry industry and public health. Migratory waterfowl are considered the natural hosts of HPAI virus, and HPAI...

Using avian radar to examine relationships among avian activity, bird strikes, and meteorological factors

Radar systems designed to detect avian activity at airfi elds are useful in understanding factors that infl uence the risk of bird and aircraft collisions (bird strikes). We used an avian radar system to measure avian activity at Beale Air Force Base, California, USA, during 2008 and 2009. We conducted a 2-part analysis to examine relationships among avian activity, bird strikes, and meteorological and time-dependent factors. We found that avian activity around the airfi eld was greater at times when bird strikes occurred than on average using a permutation resampling technique. Second, we developed generalized linear mixed models of an avian activity index (AAI). Variation in AAI was fi rst explained by seasons that were based on average migration dates of birds at the study area. We then modeled AAI by those seasons to further explain variation by meteorological factors and daily light levels within a 24- hour period. In general, avian activity increased with decreased temperature, wind, visibility, precipitation, and increased humidity and cloud cover. These effects differed by season. For example, during the spring bird migration period, most avian activity occurred before sunrise at twilight hours on clear days with low winds, whereas during fall migration, substantial activity occurred after sunrise, and birds generally were more active at lower temperatures. We report parameter estimates (i.e., constants and coeffi cients) averaged across models and a relatively simple calculation for safety offi cers and wildlife managers to predict AAI and the relative risk of bird strike based on time, date, and meteorological values. We validated model predictability and assessed model fi t. These analyses will be useful for general inference of avian activity and risk assessment efforts. Further investigation and ongoing data collection will refi ne these inference models and improve our understanding of factors that infl uence avian activity, which is necessary to inform management decisions aimed at reducing risk of bird strikes.

Mechanisms controling the timing of spring migration in birds

The question “Which factors govern the timing of migration in birds?” has fascinated researchers for a long time. It was initially assumed that avian migration is triggered by environmental factors, such as ambient temperature and food availability. Later laboratory experiments in various avian species convincingly showed that timing of spring migration is mainly governed by daylength (photoperiod) and is controlled by circannual rhythms. As a result, the concept that environmental factors (air temperature, precipitation, food availability) have no significant impact on timing of spring migration generally took hold. However, in recent decades more and more data has become available showing that the timing of spring migration in many bird species has significantly changed. These data allow the formulation of a novel concept of regulation mechanisms of timing of spring migration which accounts not only for photoperiodic and endogenous control, but also for the already mentioned extrinsic factors. Studies of endocrine control of spring migratory disposition showed that features of endocrine mechanisms governing the onset of spring migration depend on speciesspecific migratory strategies and the stability of environmental conditions in winter quarters and on migratory routes. It is becoming clear precisely which endocrine mechanisms are involved in adjusting migratory behaviour to variation of the local environment. In recent years, progress has also been made in finding genetic mechanisms controlling the timing of spring migration.

Impact of Spring Bird Migration on the Range Expansion of Ixodes scapularis Tick Population.

Many observational studies suggest that seasonal migratory birds play an important role in spreading Ixodes scapularis, a vector of Lyme disease, along their migratory flyways, and they are believed to be responsible for geographic range expansion of I. scapularis in Canada. However, the interplay between the dynamics of I. scapularis on land and migratory birds in the air is not well understood. In this study, we develop a periodic delay meta-population model which takes into consideration the local landscape for tick reproduction within patches and the times needed for ticks to be transported by birds between patches. Assuming that the tick population is endemic in the source region, we find that bird migration may boost an already established tick population at the subsequent region and thus increase the risk to humans, or bird migration may help ticks to establish in a region where the local landscape is not appropriate for ticks to survive in the absence of bird migration, imposing risks to public health. This theoretical study reveals that bird migration plays an important role in the geographic range expansion of I. scapularis, and therefore our findings may suggest some strategies for Lyme disease prevention and control.

Ecological and life history correlates of changes in avian migration timing in response to climate change

Spring migration of birds in many parts of the world has advanced as the climate has become warmer. Variation in advancement among species has been proposed to correlate with geography and life history features, but individual studies have reported variable results, and general patterns have been elusive. In a quantitative review of data from 389 bird species sampled at 69 European and 23 North American localities, we evaluated associations between change in the timing of migration and life history (body size, molt, broodedness), ecology (habitat, diet, nest position), and geography. We confirmed that spring migration advanced: -0.214 d yr-1 (95% CI: -0.266, -0.162) for first-arriving individuals and -0.104 d yr-1 (-0.139, -0.071) for the median date of passage. The rate of change in autumn was more variable: 0.090 d yr-1 (0.002, 0.176) delay for median passage and 0.019 d yr-1 (-0.175, 0.204) delay for the date of last departure. The response during spring was weaker in the far north and in species that migrate long distances to the wintering area. Autumn migration became increasingly delayed in species that are large-bodied, molt before departure, and that feed on seeds, insects, or fruits. Variation among species, especially during autumn, was associated in part with constraints surrounding the timing of the postnuptial molt. The results suggest that ecological and life history features of species may influence their ability to respond to climate change.

A database on visible diurnal spring migration of birds (Central Europe: Lake Constance)

Millions of birds migrate each year between breeding grounds and overwintering areas. Migration behavior is influenced by a number of factors: day length, physiological and genetic factors, the magnetic compass, population dynamics, and weather and climatic conditions. Historical and current data on avian migration are of broad scientific value. Most of information on avian migration is presented in form of summary statistics (e.g., duration of migration, number of individuals, trend line over years) in published studies, but original data sets are not readily available. Here, we describe the first open-source archive on visible diurnal spring migration in Central Europe. The database comprises the records of a systematic field study, which covers 35541 records of migrating birds for more than 138000 specimens of 96 species. Data were collected during the spring periods of 1984, 1985, and 1986. Bird census was conducted at the tip of the Hori peninsula in Lake Constance, Germany (north of the Alps: 47°41′...

Local Temperature Fine-Tunes the Timing of Spring Migration in Birds

Evidence for climate-driven phenological changes is rapidly increasing at all trophic levels. Our current poor knowledge of the detailed control of bird migration from the level of genes and hormonal control to direct physiological and behavioral responses hampers our ability to understand and predict consequences of climatic change for migratory birds. In order to better understand migration phenology and adaptation in environmental changes, we here assess the scale at which weather affects timing of spring migration in passerine birds. We use three commonly used proxies of spring-time climatic conditions: (1) vegetation "greenness" (NDVI) in Europe, (2) local spring temperatures in northern Europe, and (3) the North Atlantic Oscillation Index (NAO) as predictors of the phenology of avian migration as well as the strength of their effect on different subsets of populations and the dependence of correlations on species-specific migratory strategy. We analyze phenological patterns of the entire spring migration period in 12 Palaearctic passerine species, drawing on long-term data collected at three locations along a longitudinal gradient situated close to their northern European breeding area. Local temperature was the best single predictor of phenology with the highest explanatory power achieved in combination with NAO. Furthermore, early individuals are more affected by climatic variation compared to individuals on later passage, indicating that climatic change affects subsets of migratory populations differentially. Species wintering closer to the breeding areas were affected more than were those travelling longer distances and this pattern was strongest for the earliest subsets of the population. Overall, our results suggest that at least early subsets of the population are affected by local conditions and early birds use local conditions to fine-tune the date of their spring arrival while individuals arriving later are driven by other factors than local conditions e.g. endogenous control. Understanding what cues migratory organisms use to arrive at an optimum time is important for increasing our knowledge of fundamental issues like decision making in organisms during migration and is crucial for future protection of migratory organisms.

Correlates of timing of spring migration in birds: a comparative study of trans-Saharan migrants

The evolution of migratory strategies in birds is likely to have been influenced by ecological as well as socio-sexual factors in both wintering and breeding areas. In this comparative study, we analysed timing of spring passage of 38 long-distance migratory bird species that winter south of the Sahara desert and breed in Europe, in relation to wintering and breeding latitudes, moult strategy, nesting site (open vs. cavity), and sexual dimorphism in size and coloration, which may reflect intensity of sexual selection. We employed a large data set consisting of more than 190 000 individuals ringed during spring migration in the Mediterranean Sea. We found that the species that migrated earlier were those wintering farther north, nesting in cavities and showing the largest degree of sexual size dimorphism (SSD). However, sexual dichromatism was not related to migration date. Among passerine species, moulting wing-feathers in Africa delayed migration. We found no support for the energetic constraint hypothesis, which proposes that early arrival selects for large male size, since early arriving species were not larger than late arriving ones. Thus, the observed associations suggest that variation in migration schedules at the interspecific level may have evolved in relation to ecological factors and SSD, possibly reflecting the intensity of mating competition. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society, 2005, 85, 199–210.

Timing of spring migration in birds: long‐term trends, North Atlantic Oscillation and the significance of different migration routes

We studied long‐term trends and the yearly variation in mean spring passage time in 36 passerine bird species trapped at Ottenby Bird Observatory in south‐eastern Sweden. Between the years 1952–2002, data were available for 22–45 years depending on species. Most long‐distance migrant species passed progressively earlier over the study period (range: 2.5 days earlier to 0.7 days later per 10 years, with an average of 0.9 days earlier per 10 years). The annual variation in timing of migration in most species, regardless of migration distance, correlated negatively with the winter index of the North Atlantic Oscillation (NAO), a large‐scale climate phenomenon influencing the climate in the North Atlantic region. Birds passed earlier after mild and humid winters, corresponding to the high phase of the NAO. This corroborates the pattern found at a nearby migration site with a comparable dataset (Helgoland, 600 km WSW of Ottenby). However, short/medium‐distance migrant species at Ottenby, in contrast to the situation at Helgoland, have shown no general trend of earlier passage in recent years. This was probably a consequence of the shorter study period at Ottenby, which included only the last 22–32 years (41 years at Helgoland), when the NAO showed no significant trend. At the species‐specific level, the long‐term trends in passage time were similar at the two sites, and there was some congruence to the extent that a given species was affected by NAO. Long‐distance migrants wintering south and south‐east of the breeding grounds showed some of the strongest changes in long‐term trends (passing progressively earlier) at Ottenby, and for some of these species passage time varied negatively with NAO. Obviously, and contrary to previous suggestions, variations in NAO also influence birds migrating through eastern Europe, although the direct or indirect mechanisms through which this is achieved are unknown.

North Atlantic Oscillation and timing of spring migration in birds.

Migrant birds have been trapped on the island of Helgoland (southeastern North Sea) since 1909, with methods and sampling effort remaining unchanged throughout the last four decades. In 12 short/medium-distance migrants and 12 long-distance migrants (23 passerines plus the European woodcock) sample sizes were sufficient to calculate mean spring passage (msp) times and to relate these to climate change. All but one species, passing Helgoland en route to their breeding areas (mainly in Scandinavia), show a trend towards earlier msp-time, which is significant in 7 short/medium-distance migrants and 10 long-distance migrants. The msp-times advanced by 0.05-0.28 days per year, short/medium-distance migrants not differing from long-distance migrants. In 23 out of the 24 species, earlier msp-times coincide with local warmer msp-temperatures (significantly in 11 and 7 species of the two groups, respectively). Even more striking is the relation to a large-scale phenomenon, the North Atlantic Oscillation (NAO), during the last four decades. Again, in 23 out of the 24 species, an earlier msp-time coincides with higher NAO indices (significantly in 9 and 12 species, respectively). The NAO index can also explain differences and similarities in spring migration strategies, as well as migration routes within Europe.

Sexual size dimorphism and timing of spring migration in birds

Sexually selected traits are limited by selection against those traits in other fitness components, such as survival. Thus, sexual selection favouring large size in males should be balanced by higher mortality of larger males. However, evidence from red-winged blackbirds (Agelaius phoeniceus) indicates that large males survive better than small males. A survival advantage to large size could result from males migrating north in early spring, when harsh weather favours large size for energetic reasons. From this hypothesis we predicted that, among species, sex differences in body size should be correlated with sex differences in timing of spring migration. The earlier males migrate relative to females, the larger they should be relative to females. We tested this prediction using a comparative analysis of data collected from 30 species of passerine birds captured on migration. After controlling for social mating system, we found that sexual size dimorphism and difference in arrival dates of males and females were significantly positively correlated. This result is consistent with the hypothesis that selection for survival ability promotes sexual size dimorphism (SSD), rather than opposes SSD as is the conventional view. If both natural selection and sexual selection favour large adult males, then limits to male size must be imposed before males become adults.

Spring Bird Migration in Mississippi Alluvial Valley Forests

We surveyed forest songbirds during migration in bottomland hardwood forest stands and managed cottonwood (Populus deltoides) plantations in northeast Louisiana and west-central Mississippi between 24 March and 24 May 1996 and 1997. We detected more bird species in bottomland hardwood stands than in cottonwood stands. Within hardwood stands, we detected more individuals in stands subjected to uneven-aged timber harvest than in unmanaged stands. Early in migration, avian species composition was similar in both forest types, being comprised mainly of short-distance migrants. Bird species composition in these forest types became increasingly disparate as long-distance neotropical-nearctic migrants arrived. Ten bird species were characteristic of bottomland hardwood forests, whereas eight different species were characteristic of managed cottonwood plantations. Because these two forest types supported different bird communities, both forest types provide important inland stopover habitat during migration. Silvicultural management of bottomland hardwood forests that increases their understory vegetation will provide forested habitat for a more species rich and abundant population of songbirds during migration.

Avifauna during Spring Migration on Taira-jima Island, Tokara Islands

Spring bird migration was investigated on Taira-jima Island (29°41′N, 129°32′E), Tokara Islands, Kagoshima Prefecture, from 1982 to 1987. Twenty nine families and 122 species were recorded in total and 66 birds with 30 species were ringed and released, including such unusual species as Muscicapa ferruginea, Turdus hortulorum, and Ficedula zanthopygia. Most species seemed to use this island on the way of the northward migration through the Ryukyu and Amami Islands. But several species, such as Erithacus cyane, Phylloscopus occipitalis, Regulus regulus, and Cyanoptilla cyanomelana are rare or unrecorded on the Ryukyus and Taiwan, suggesting a direct migratory course from south-eastern China to Kyushu.

Weather Conditions Associated with Beginning of Northward Migration Departures of Snow Geese

The relationship between spring migration of birds and weather conditions has been examined in many studies. Theories on weather factors that might stimulate spring migrations resulted from correlating local weather conditions with observed flights of birds aloft or already en route during migration, especially in April and May. No studies have related weather conditions with actual beginnings of spring migration of birds from their winter areas. Numerous relation-

Handbook of the Birds of Europe, the Middle East and North Africa; the Birds of the Western Palearctic

1983 — Handbook of the Birds of Europe, the Middle East and North Africa. The Birds of Western Palearctic, vol. 3 — Oxford University Press, Oxford, 913 pp. Handbook of the Birds of Europe, the Middle East and North Africa: The Birds of the Western Palearctic by CRAMP, Stanley et al. (eds) and a great selection. AERC TAC Checklist of bird taxa occurring in Western Palearctic region, 15th Draft. Available at: Handbook of the birds of Europe, the Middle East and Africa. The birds of the North Atlantic Oscillation and timing of spring migration in birds.

Records of Spring Migration of Birds at Urbana, Illinois, 1903-1922

The chief object in view in the preparation of this paper has been to make available to those interested certain data connected with spring bird migration activities in East Central Illinois in tlie vicinity of Urbana.

Lewis on the Birds of Antigonish, Nova Scotia Notes on Spring Bird Migration of 1914 at Antigonish, N. S. Harrison F. Lewis

Lewis on the Birds of Antigonish, Nova Scotia Notes on Spring Bird Migration of 1914 at Antigonish, N. S. Harrison F. Lewis

Abstracts

During September 2018, a tick was submitted to Public Health England’s Tick Surveillance Scheme for identification. The tick was sent from a veterinarian who removed it from a horse in Dorset, England, with no history of overseas travel. The tick was identified as a male Hyalomma rufipes using morphological and molecular methods and then tested for a range of tick-borne pathogens including; Alkhurma virus, Anaplasma, Babesia, Bhanja virus, Crimean-Congo Haemorrhagic fever virus, Rickettsia and Theileria. The tick tested positive for Rickettsia aeschlimannii, a spotted fever group rickettsia linked to a number of human cases in Africa and Europe. This is the first time H. rufipes has been reported in the United Kingdom (UK), and the lack of travel by the horse (or any in-contact horses) suggests that this could also be the first evidence of successful moulting of a Hyalomma nymph in the UK. It is postulated that the tick was imported into the UK on a migratory bird as an engorged nymph which was able to complete its moult to the adult stage and find a host. This highlights that passive tick surveillance remains an important method for the detection of unusual species that may present a threat to public health in the UK. Horses are important hosts of Hyalomma sp. adults in their native range, therefore, further surveillance studies should be conducted to check horses for ticks in the months following spring bird migration; when imported nymphs may have had time to drop off their avian host and moult to adults. The potential human and animal health risks of such events occurring more regularly are discussed.