Temporal Changes in Wing Length, Fat Reserves and Body Mass of Migrating Eurasian Blackcaps Sylvia atricapilla at a West Hungarian Stopover Site

Abstract Philopatry to stopover site and changes in body condition of migrating Reed Warblers Acrocephalus scirpaceus were studied in Bet Shean Valley, Israel, where warblers were netted throughout the year. Although the majority of birds were seen only once, the proportion of transients seen twice or more in different years is comparable to the figure for summer residents returning between years, indicating a high degree of philopatry among transients. Transients get heavier with longer duration of stay, up to about 15 days, after which body mass increase appears to level off at about 3 g. Change in body condition, taken to be body mass divided by wing length, also was noted, albeit of less significance. The mean date of arrival in the autumn of birds in their first year was about 20 days later than that of older birds. Reed Warblers use their time effectively to replenish their body mass and improve their condition before starting the dangerous crossing of the Sahara Desert.

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Biometry of young White Wagtails (Motacilla alba) and Yellow Wagtails (Motacilla flava) caught in the Gulf of Gdańsk region during autumn migration

Ring ◽

10.2478/v10050-008-0010-5 ◽

2005 ◽

Vol 27 (1) ◽

pp. 69-78

Author(s):

Marcin Polak

Keyword(s):

Body Mass ◽

Wing Length ◽

Length Distribution ◽

Autumn Migration ◽

Gulf Of Gdańsk ◽

Fat Reserves ◽

Stopover Sites ◽

Motacilla Alba ◽

Gulf Of Gdansk ◽

Two Peaks

Biometry of young White Wagtails (Motacilla alba) and Yellow Wagtails (Motacilla flava) caught in the Gulf of Gdańsk region during autumn migration Biometrics of juvenile 760 White Wagtails and 714 Yellow Wagtails migrating through the Gulf of Gdańsk region in autumn were studied between 1990 and 2000. In both species distributions of wing length, body mass and indices of wing shape were unimodal, with only one exception - in the White Wagtail the wing length distribution showed two peaks caused by sexual dimorphism. The mean body mass and reserves of fat in both species were low in comparison to other stopover sites. There were significant differences in mean weight between birds caught in the morning and in the evening. The majority of birds behave as energy minimising migrants and migrate with low fat reserves in small steps.

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Association of weather variables with the migration phenology and body conditions of Siberian warblers

Ornis Fennica ◽

10.51812/of.113447 ◽

2022 ◽

Vol 98 (4) ◽

pp. 162-174

Author(s):

László Bozó ◽

Yury Anisimov ◽

Tibor Csörgő

Keyword(s):

Body Mass ◽

Body Condition ◽

Weather Conditions ◽

The Body ◽

Autumn Migration ◽

Weather Variables ◽

Stopover Site ◽

Migration Timing ◽

Fat Reserves ◽

The Impact

Different elements of weather, such as wind speed, wind direction, precipitation and temperature are very important regulators of bird migration. Weather conditions also play role on the body condition such as body mass and the deposited fat. In this study we selected four warbler species to examine the impact of different weather variables on their spring and autumn migration timing and their body condition in one of the most extreme weather areas of the Earth, at Lake Baikal in Siberia. We also studied the changes in body mass and fat reserves during the spring and autumn migration periods of these species. For the analyses, we used ringing data of 2471 birds from five spring and five autumn seasons during 2015–2019. According to our results, it can be stated that the weather did not have a significant association with the migration timing of the studied warblers, perhaps due to the geographical location of the study site. However, the body mass and the fat reserves of the birds increased during unsuitable weather conditions because of the increased energy requirements. Birds generally migrate with low fat reserves, which is due to the fact that this area is not an important stopover site for these species.

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Sex and age-specific differences in wing pointedness and wing length in blackcaps Sylvia atricapilla migrating through the southern Baltic coast

Current Zoology ◽

10.1093/cz/zoaa065 ◽

2020 ◽

Author(s):

Agnieszka Ożarowska ◽

Grzegorz Zaniewicz ◽

Włodzimierz Meissner

Keyword(s):

Wing Length ◽

Sub Saharan Africa ◽

Migration Route ◽

Sylvia Atricapilla ◽

Climatic Effects ◽

Migration Distance ◽

Baltic Coast ◽

Southern Baltic ◽

Sub Saharan ◽

Migrating Birds

Abstract The blackcap Sylvia atricapilla shows a complex migratory pattern and is a suitable species for the studies of morphological migratory syndrome, including adaptations of wing shape to different migratory performance. Obligate migrants of this species that breed in northern, central, and Eastern Europe differ by migration distance and some cover shorter distance to the wintering grounds in the southern part of Europe/North Africa or the British Isles, although others migrate to sub-Saharan Africa. Based on ˃40 years of ringing data on blackcaps captured during autumn migration in the Southern Baltic region, we studied age- and sex-related correlations in wing pointedness and wing length of obligate blackcap migrants to understand the differences in migratory behavior of this species. Even though the recoveries of blackcaps were scarce, we reported some evidence that individuals which differ in migration distance differed also in wing length. We found that wing pointedness significantly increased with an increasing wing length of migrating birds, and adults had longer and more pointed wings than juvenile birds. This indicates stronger antipredator adaptation in juvenile blackcaps than selection on flight efficiency, which is particularly important during migration. Moreover, we documented more pronounced differences in wing length between adult and juvenile males and females. Such differences in wing length may enhance a faster speed of adult male blackcaps along the spring migration route and may be adaptive when taking into account climatic effects, which favor earlier arrival from migration to the breeding grounds.

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Sex and age dependent migration phenology of the Pied Flycatcher in a stopover site in the Carpathian Basin

Ornis Hungarica ◽

10.1515/orhu-2015-0010 ◽

2015 ◽

Vol 23 (2) ◽

pp. 10-19 ◽

Cited By ~ 6

Author(s):

Andrea Harnos ◽

Zsolt Lang ◽

Péter Fehérvári ◽

Tibor Csörgő

Keyword(s):

Wing Length ◽

Carpathian Basin ◽

Stopover Site ◽

The Past ◽

Age Related ◽

Phenological Changes ◽

Comprehensive Picture ◽

Migration Phenology ◽

And Gender ◽

Gender Groups

Abstract Very little is known about Pied Flycatchers crossing the Carpathian Basin. We give a comprehensive picture about its migration based on the data collected during the past 26 years (1989–2014) at a stopover site in Hungary: (1) sex and age related phenological changes over the years, (2) sex, age and size dependent migration patterns during and (3) between migration periods, (4) sex and age composition in spring and in autumn and their change over years. The timing of spring migration shifted to earlier dates in the case of males, while that of females did not change implying an increasing rate of protandry. In autumn the timing did not change, but juveniles leave the area earlier than adults. The average wing length increased during the past decades in spring in the case of both sexes. In autumn, wing length did not change significantly during the years, but it increased during the seasons in all age and gender groups. The proportion of males is about 60% in spring and among juveniles in autumn, and it is around 39% in the adult group in autumn. The male ratio diminishes during spring, but it does not change during the autumn season. The average wing of adults is shorter in spring than in autumn. Based on this fact and the different sex ratios in the two seasons we may hypothesize that Pied Flycatchers are loop migrants on this area, and even the sexes of the same population take different routes.

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Patterns of Growth in Nestling Indian Barn-Owls

The Condor ◽

10.1093/condor/104.4.885 ◽

2002 ◽

Vol 104 (4) ◽

pp. 885-890 ◽

Cited By ~ 1

Author(s):

Rajarathinavelu Nagarajan ◽

Krishinamoorthy Thiyagesan ◽

Rajagopalan Natarajan ◽

Ramalingam Kanakasabai

Keyword(s):

Body Mass ◽

Body Length ◽

Wing Length ◽

Growth Patterns ◽

The Body ◽

Logistic Growth ◽

Adult Size ◽

Tyto Alba ◽

Tarsus Length ◽

Bill Length

Abstract We examined nestling growth patterns of the Indian Barn-Owl (Tyto alba stertens) in Tamilnadu, Southern India, with reference to body mass, body length, bill length, bill width, wing length, wingspan, tail length, tarsus length, and middle claw length. Body mass reached an asymptote of 447.0 ± 6.8 g during week 7, which was 10% higher than the adult mass. Then it significantly declined to 437.0 ± 10.9 g at fledging. At the end of week 4, the body length, bill length, bill width, tarsus length, and middle toe length had surpassed 50% of adult sizes. The wingspan and tarsus length reached almost adult size by the time of fledging. A logistic growth curve was found to be a good fit for all the growth variables and explained between 71% (wing length) and 86% (body length) of the variance. Patrones de Crecimiento en Polluelos de Tyto alba stertens Resumen. Examinamos los patrones de crecimiento de polluelos de Tyto alba stertens en Tamilnadu, sudoeste de India, en relación al peso y el largo del cuerpo, el largo y el ancho del pico, el largo del ala y su envergadura, y el largo de la cola, los tarsos y de la garra mediana. El peso corporal alcanzó una asíntota de 447.0 ± 6.8 g durante la séptima semana, el cual fue un 10% mayor que el peso de los adultos. Posteriormente, durante el período de volantones, el peso corporal disminuyó hasta 437.0 ± 10.9 g. Al final de la cuarta semana, el largo del cuerpo, el largo y el ancho del pico, y los largos del tarso y del dedo mediano habían sobrepasado el 50% de los tamaños adultos. La envergadura del ala y el largo del tarso casi alcanzaron tamaños adultos durante el período de volantones. Se encontró que una curva de crecimiento logístico se ajustó bien a todas las variables de crecimiento y explicó un 71% (largo del ala) y un 86% (largo del cuerpo) de la varianza.

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Developmental speed affects ecological stoichiometry and adult fat reserves in Drosophila melanogaster

Animal Biology ◽

10.1163/15707563-bja10043 ◽

2020 ◽

Vol 71 (1) ◽

pp. 1-20

Author(s):

Indrikis A. Krams ◽

Ronalds Krams ◽

Priit Jõers ◽

Māris Munkevics ◽

Giedrius Trakimas ◽

...

Keyword(s):

Body Composition ◽

Drosophila Melanogaster ◽

Body Mass ◽

Developmental Plasticity ◽

Nitrogen Concentration ◽

Fruit Flies ◽

Climatic Conditions ◽

Feeding Rates ◽

Nitrogen Levels ◽

Fat Reserves

Abstract The elemental composition of organisms belongs to a suite of functional traits that change during development in response to environmental conditions. However, associations between adaptive variations in developmental speed and elemental body composition are not well understood. We compared body mass, elemental body composition, food uptake and fat metabolism of Drosophila melanogaster male fruit flies in relation to their larval development speed. Slowly developing flies had higher body carbon concentration than rapidly developing and intermediate flies. Rapidly developing flies had the highest body nitrogen concentration, while slowly developing flies had higher body nitrogen levels than flies with intermediate speed of development. The carbon-to-nitrogen ratio was therefore lower in rapidly developing flies than in slow and intermediate flies. We also had a group of flies grown individually and their body mass and elemental body composition were similar to those of rapidly developing individuals grown in groups. This suggests that rapid growth is not suppressed by stress. Feeding rates were lowest in the slowly developing flies. The amount of triacylglycerides was highest in the flies with intermediate developmental speed which optimizes development under many climatic conditions. Although low food intake slows down developmental speed and the accumulation of body fat reserves in slowly developing flies, their phenotype conceivably facilitates survival under higher stochasticity of their environments. Rapidly developing flies grew with less emphasis on storage build-up. Overall, this study shoes that a combination of bet-hedging, adaptive tracking and developmental plasticity enables fruit flies to respond adaptively to environmental uncertainty.

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Autumnal body mass reduction in Antechinus swainsonii (Dasyuridae) in the Snowy Mountains.

Australian Mammalogy ◽

10.1071/am01031 ◽

2001 ◽

Vol 23 (1) ◽

pp. 31 ◽

Cited By ~ 5

Author(s):

K Green

Keyword(s):

Snow Cover ◽

Body Mass ◽

Lean Mass ◽

Late Summer ◽

Mass Reduction ◽

Average Mass ◽

Increase Body Mass ◽

Fat Reserves ◽

The Difference ◽

Body Mass Reduction

Autumnal body mass reduction in a seasonally snow-covered environment is reported for Antechinus swainsonii (Marsupialia: Dasyuridae), thus extending the phylogenetic spectrum in which this phenomenon is known. Above 1600 m altitude the average mass of individual A. swainsonii falls from 48.6 g to 42.6 g (a 12.3% loss) from April to May. The difference in mass results from a reduction in lean mass rather than a metabolisation of fat reserves. In A. swainsonii, the need to increase body mass in late summer only to lose it in autumn prior to a winter beneath the snow seems superfluous. However, the higher mass may be necessary to survive the harsher microclimate in autumn before conditions ameliorate beneath the snow cover. Survival from April to May is higher in heavier animals (that do lose mass in autumn) than lighter animals (with mass in April equal to that of animals after loss of body mass). These lighter animals disappear from the population in autumn. With snow cover in place, A. swainsonii is able to increase mass in winter.

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RELATIONSHIPS AMONG BODY MASS, FAT, WING LENGTH, AGE, AND SEX FOR 170 SPECIES OF BIRDS BANDED AT POWDERMILL NATURE RESERVE

The Wilson Bulletin ◽

10.1676/0043-5643(2004)116[0189:ol]2.0.co;2 ◽

2004 ◽

Vol 116 (2) ◽

pp. 189-190

Author(s):

ERICA H. DUNN

Keyword(s):

Body Mass ◽

Nature Reserve ◽

Wing Length ◽

Age And Sex

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Changes in migration phenology and biometrical traits of Reed, Marsh and Sedge Warblers

Open Life Sciences ◽

10.2478/s11535-011-0101-1 ◽

2012 ◽

Vol 7 (1) ◽

pp. 115-125 ◽

Cited By ~ 5

Author(s):

Szilvia Kovács ◽

Péter Fehérvári ◽

Krisztina Nagy ◽

Andrea Harnos ◽

Tibor Csörgő

Keyword(s):

Body Mass ◽

Population Level ◽

Long Distance ◽

Stopover Site ◽

Sedge Warbler ◽

Global Environmental ◽

Migration Phenology ◽

Spring Arrival ◽

Migration Strategies ◽

Migrant Birds

AbstractGlobal environmental processes like climate change could severely affect population level migratory behaviour of long range migrant birds. We analyzed changes in migration phenology and biometrics of three closely-related long-distance migrant Acrocephalus species. We used the records of 12 063 Sedge, 12 913 Reed, and 5 409 Marsh Warblers caught and ringed between 1989–2009, at a Hungarian stopover site. Quantile regressions were used to analyse the changes in spring and autumn migration phenology. Median spring arrival date of Sedge and Reed Warblers shifted 6.5 and 7.5 days earlier, respectively. Autumn arrival of all species shifted one (Reed and Marsh Warblers) or two (Sedge Warbler) weeks later. Mean body mass of adult Reed and Marsh Warblers decreased in spring (by 0.3 and 0.2 grams, respectively) and in autumn (by 0.8 and 0.2 grams, respectively) while body mass of adult Sedge Warblers decreased only in autumn (by 0.4 grams). Mean wing length of all species increased significantly (range of change: 0.6–1 mm). Despite the fact that the studied species are closely related, all three have remarkably different migration strategies. However, similar patterns can be observed in the studied parameters, indicating that global processes may have general effects on these species, albeit through markedly different mechanisms.

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