Migration Dynamics and Seasonal Variation In the Biometrics of the Eurasian Curlew (Numenius arquata) Migrating through the Lower Vistula Valley (N Poland) in Autumn

Ring ◽  
2009 ◽  
Vol 31 (1) ◽  
pp. 41-51
Author(s):  
Robert Krupa ◽  
Włodzimierz Meissner ◽  
Małgorzata Krupa ◽  
Agnieszka Sereda
Keyword(s):  
Seasonal Variation ◽  
Wing Length ◽  
Bimodal Distribution ◽  
Linear Measurements ◽  
Stopover Site ◽  
Breeding Range ◽  
Total Head ◽  
Timing Of Migration ◽  
Migration Dynamics ◽  
Almost All

Migration Dynamics and Seasonal Variation In the Biometrics of the Eurasian Curlew (Numenius arquata) Migrating through the Lower Vistula Valley (N Poland) in Autumn The aim of this study was to present data on the phenology of autumn migration of the Eurasian Curlew passing the lower Vistula valley and to determine whether there is a difference in biometrics between early and late migrants, which may reflect different timing of migration of birds from different parts of the breeding range. Studies were conducted in the lower Vistula valley in 2003-2008. Median date of migration fell into 9-13 August pen-tade. The migration dynamics showed major day-to-day changes in bird numbers and almost all of observed flocks migrated without staying in the study area. Moreover, only one bird was caught twice during the season. It indicates that lower Vistula valley is not an attractive stopover site for Eurasian Curlews. There were significant differences in the total head lengths, bill lengths and body masses of birds caught in different ten-days periods with larger and heavier birds occurring towards the end of the study period (ANOVA, Neuman-Keuls test: p < 0.05 in all cases). The gradual increase in the total head and bill lengths and probably also in body mass indicates that bigger birds from the eastern part of the breeding range migrate later than smaller birds, which breed in the west. There were no significant differences in wing length, tarsus length and tarsus with toe length (ANOVA, Neuman-Keuls test: p > 0.05 in all cases). Subspecies N. a. arquata and N. a. orientalis have similar wing length and in this study there were no significant differences for this measurement between following decades of the studied period. Collected data suggest that the wing length, which had clearly bimodal distribution, should be the best linear measurements for sexing at least juvenile Eurasian Curlews.

Cranial morphology and systematics of an extraordinary sample of the Late Neogene dwarf tapir, Tapirus polkensis (Olsen)

2009 ◽  
Vol 83 (2) ◽  
pp. 238-262 ◽  
Author(s):  
Richard C. Hulbert ◽  
Steven C. Wallace ◽  
Walter E. Klippel ◽  
Paul W. Parmalee
Keyword(s):  
Single Species ◽  
Relative Strength ◽  
Cranial Morphology ◽  
Linear Measurements ◽  
Average Mass ◽  
Gray Fossil Site ◽  
Extant Species ◽  
Late Neogene ◽  
Fossil Site ◽  
Almost All

The previously poorly known “Tapiravus” polkensis Olsen, 1960 (Mammalia, Perissodactyla, Tapiridae) is now known from abundant, well preserved specimens from both the type area in central Florida and from the Gray Fossil Site (GFS) in eastern Tennessee. The latter has produced over 75 individuals, the greatest number of tapirids from a single fossil site, including many articulated skeletons. Almost all linear measurements taken on skulls, mandibles, and cheek teeth from GFS have coefficients of variation less than 10 (most between 3 and 7), indicating the presence of a single species. However, the sample reveals considerable intraspecific variation for a few key morphologic features, including development of the sagittal crest, outline shape of the nasals, and number and relative strength of lingual cusps on the P1. The Florida sample of T. polkensis is more limited, but has the same state as the GFS sample for all preserved characters of systematic significance, and while the Florida teeth are on average smaller (especially narrower lower cheek teeth), they fall either within or just below the observed range of the Gray Fossil Site population. The new material supports a reassignment of “Tapiravus” polkensis to the genus Tapirus, and demonstrates that the geologic age of the species is significantly younger than previously thought, Hemphillian rather than Barstovian. Tapirus polkensis is the smallest known North American Tapirus, and smaller than any of the extant species in the genus, with an estimated average mass of 125 kg.

scholarly journals Population and reproductive traits of a freshwater amphipod (Crustacea, Peracarida, Hyalellidae) from northwest of the state of Rio Grande do Sul, Brazil

2020 ◽  
Vol 20 (2) ◽  
Author(s):  
Daniela da Silva Castiglioni ◽  
Marcio Limberger ◽  
Vanessa da Silva Castro ◽  
Francieli Ubessi
Keyword(s):  
No Reduction ◽  
Natural Populations ◽  
Reproductive Traits ◽  
Bimodal Distribution ◽  
Southern Brazil ◽  
Natural Pond ◽  
Males And Females ◽  
The Mean ◽  
Anthropic Influence ◽  
Almost All

Abstract The study of population and reproductive traits provides information about the ecological structure of natural populations. This study aimed to characterize dynamics and reproductive traits of Hyalella palmeirensis from a natural pond from southern Brazil. The amphipods were sampled monthly (August 2012 to July 2013) by a person with the aid of a hand net for 20 minutes. Ovigerous females and pre-copulatory pairs were individualized in the field. A total of 12,325 individuals were sampled, being 1,421 males, 6,983 females (including 215 ovigerous females) and 3,921 juveniles. Paired and unpaired males were significantly greater in size than females. There was a positive correlation between body size (CL) of paired males and females. Males and females showed bimodal distribution. Total sex ratio favored females, and these were more frequent in almost all months. Ovigerous females and precopulatory pairs were found throughout the year, but with high frequency in winter and autumn, respectively, characterizing a seasonal reproduction. Juveniles were sampled throughout the year, with greater intensity in the spring. The mean fecundity was 19.6 ± 4.34 eggs. No reduction in the number of eggs was observed during embryonic development. The results observed in H. palmeirensis demonstrate that this species has a population and reproductive dynamics very similar to other species of Hyalella already analyzed in southern Brazil. Moreover, it can be seen that although the H. palmeirensis occurs in an environment with anthropic influence (soy cultivation,) the population is managing to remain in the area, with reproduction and recruitment in most months of year.

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

2015 ◽  
Vol 23 (2) ◽  
pp. 10-19 ◽  
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.

Tourism Migration in South Africa

2017 ◽  
Vol 8 (1) ◽  
pp. 47-60
Author(s):  
Unathi Sonwabile Henama ◽  
Portia Pearl Siyanda Sifolo
Keyword(s):  
South Africa ◽  
South African ◽  
Critical Phenomenon ◽  
Economic Benefits ◽  
Tourism Industry ◽  
Future Prospects ◽  
Volunteer Tourism ◽  
Migration Dynamics ◽  
And Migration ◽  
Almost All

This article explores the tourism migration within the South African context, thereby focusing on the current dynamics, challenges and future prospects. Tourism and migration are significant towards globalisation. Almost all countries have jumped on the tourism bandwagon as a result of the positive economic benefits that include improving the balance of payments, attracting foreign exchange, and increasing state coffers through the taxation of non-residents. South Africa has also adopted tourism into the developmental policies. Although Africa's share of the global tourism market remains less than 10%, the continental bodies such as the African Union under the wing NEPAD recognises that tourism and migration as an important factor to societies. This paper adopts the content analysis to address the tourism migration, dynamics, challenges and future prospects as a critical phenomenon. Tourism has deep characteristics of a plantation economy that does not benefit the majority of the societies, particularly in South Africa. Despite being a geographical dispersed country, the tourism industry in South Africa faces numerous challenges such as the integration of Black South Africans as product owners; reported high rates of crimes, lack of integration of locals in the tourism industry, the lack of aviation competition, paucity of ports of entry, and most recently the cyber-crime and the visa regulations etc. However, South African tourism remains resilient as a major destination due to its fauna and flora and increasing market niches are developing such as adventure tourism, health tourism and volunteer tourism. South Africa plans to be one of the top 20 destinations by 2020; steps are in place to ensure that South Africa achieves this objective.

scholarly journals Trends in the seasonal variation of paediatric fractures

2018 ◽  
Vol 12 (6) ◽  
pp. 614-621 ◽  
Author(s):  
D. Segal ◽  
O. Slevin ◽  
E. Aliev ◽  
O. Borisov ◽  
B. Khateeb ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
Sedentary Lifestyle ◽  
Bimodal Distribution ◽  
Trauma Centre ◽  
Fracture Rate ◽  
Prevention Measures ◽  
Level Of Evidence ◽  
Summer Vacation ◽  
Institutional Review ◽  
Hot Weather

Purpose The incidence of paediatric fractures is known to peak during the summer as a consequence of unsupervised physical activity. A more sedentary lifestyle is a potential cause for changes in paediatric seasonal fracture frequency and severity. The aim of this study was to evaluate the current seasonal variations of paediatric fractures in order to determine resource allocation in hospitals, community clinics and prevention programs. Methods A single institutional review of historical data of all patients aged 0 to 16 years that were diagnosed with fractures between April 2014 and July 2017 in the emergency department of a level 3 orthopaedic trauma centre was conducted. In all, 3484 fractures were reviewed, of which 2991 were included. We stratified fractures according to patients’ variants and the hour, day and month with respect to holidays, weekends and weather. Results While the fracture rate on school days was 6.62 per day, the fracture rate during the summer vacation was 4.45 (p < 0.01). Hot weather was correlated with low fracture rates. The peak hours of admission were 12:00 to 13:00 and 18:00 to 22:00, with more moderate differences during non-school periods. Conclusion The local seasonal variation of paediatric fractures has a bimodal distribution, with similar nadirs during both summer and winter. These rates might reflect a shift to a more sedentary lifestyle during the summer vacation. The presented data can assist in improving the value of injury prevention measures and medical resources allocation. Level of evidence: II

scholarly journals Philopatry to Stopover Site and Body Condition of Transient Reed Warblers During Autumn Migration Through Israel

The Condor ◽  
2000 ◽  
Vol 102 (2) ◽  
pp. 441-444 ◽  
Author(s):  
Kobi Merom ◽  
Yoram Yom-Tov ◽  
Robin McClery
Keyword(s):  
Body Mass ◽  
Body Condition ◽  
Wing Length ◽  
First Year ◽  
Sahara Desert ◽  
Stopover Site ◽  
Acrocephalus Scirpaceus ◽  
The Mean ◽  
High Degree ◽  
Mass Increase

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.

scholarly journals Autumn Migration Of The Thrush Nightingale (Luscinia Luscinia) In Northern Hungary

Ring ◽  
2012 ◽  
Vol 34 (1) ◽  
pp. 23-36 ◽  
Author(s):  
Dávid Kováts
Keyword(s):  
Arrival Time ◽  
Wing Length ◽  
Age Groups ◽  
Autumn Migration ◽  
Stopover Site ◽  
Migration Strategies ◽  
Median Date ◽  
The Mean ◽  
Fat Score ◽  
Thrush Nightingale

Abstract Kováts D. 2012. Autumn migration of the Thrush Nightingale (Luscinia luscinia) in northernHungary. Ring 34: 23-36. The autumn migration of the Thrush Nightingale was studied in Szalonna in northern Hungary in 1989-2010. Birds were mist-netted, ringed, aged, measured, weighed and fat scored. In total, 193 Thrush Nightingales were ringed during 22 years. Relations between arrival time and biometrical measurements were determined. Within the study period (6 August - 26 September) the migration curve was bimodal showing maximum on 22 August and 27 August. Immature birds arrived significantly earlier with lower body mass and shorter wing length and had more pointed wings in the first half of their passage. The distribution of fat score classes did not differ significantly between the early and late periods of the most intensive migration, although the mean of the deposited fat was the lowest during the peak of migration. Fat reserve distribution was bimodal in autumn suggesting that Thrush Nightingales probably start their journey from different breeding ranges (populations) or follow still undiscovered migration strategies of sex/age groups. The low proportion of recaptures proved that the area was not used as a stopover site or premigratory fattening area. Within 22 years of study, the median date of autumn migration of Thrush Nightingales shifted 7.9 days earlier, probably due to current climate change.

Seasonal Variation of Backcalculated Subgrade Moduli

1997 ◽  
Vol 1577 (1) ◽  
pp. 70-80 ◽  
Author(s):  
Bing Long ◽  
Mustaque Hossain ◽  
Andrew J. Gisi
Keyword(s):  
Seasonal Variation ◽  
Moisture Content ◽  
Temperature Effect ◽  
Resilient Modulus ◽  
Natural Soil ◽  
Temperature Regimes ◽  
Almost All ◽  
Moisture Conditions ◽  
Falling Weight ◽  
And Behavior

Seasonal variations in pavement material properties and behavior due to variations in temperature and moisture conditions are known to affect the structural performance of pavement. Temperature, subgrade moisture content, and falling weight deflectometer (FWD) deflection data were collected monthly on four asphalt pavement test sections for a year. Subgrade moduli were backcalculated using the elastic layer theory with two calculation schemes and pavement models. Backcalculation of subgrade moduli by subdividing the subgrade into a compacted subgrade layer and a natural soil subgrade layer resulted in compacted subgrade moduli that are more sensitive to the seasonal variation for all sites. It was found that for almost all sites, the patterns of subgrade response, in terms of subgrade moduli versus subgrade moisture content, simulated sine-shaped forms signifying a temperature effect. The temperature effect was confirmed by the strong correlation between backcalculated subgrade moduli and pavement surface temperature during FWD tests. The lowest backcalculated subgrade moduli were obtained for two sections during months when asphalt surface temperatures were excessively high (greater than 40°C). Both backcalculation schemes showed similar trends in variation of subgrade moduli over seasons. When the AASHTO relative damage concept was used to compute the effective roadbed soil resilient modulus for design, similar values were found for both schemes for most of the sites. The minimum frequency of FWD testing to capture the seasonal variation of subgrade was found to be three tests per year, or testing every fourth month, assuming that unusually high temperature regimes could be avoided.

scholarly journals Ghrelin affects stopover decisions and food intake in a long-distance migrant

2017 ◽  
Vol 114 (8) ◽  
pp. 1946-1951 ◽  
Author(s):  
Wolfgang Goymann ◽  
Sara Lupi ◽  
Hiroyuki Kaiya ◽  
Massimiliano Cardinale ◽  
Leonida Fusani
Keyword(s):  
Food Intake ◽  
Peptide Hormone ◽  
Migratory Behavior ◽  
Migratory Restlessness ◽  
Long Distance ◽  
Stopover Site ◽  
Blood Concentrations ◽  
Timing Of Migration ◽  
Fat Stores ◽  
Sylvia Borin

Billions of birds migrate long distances to either reach breeding areas or to spend the winter at more benign places. On migration, most passerines frequently stop over to rest and replenish their fuel reserves. To date, we know little regarding how they decide that they are ready to continue their journey. What physiological signals tell a bird’s brain that its fuel reserves are sufficient to resume migration? A network of hormones regulates food intake and body mass in vertebrates, including the recently discovered peptide hormone, ghrelin. Here, we show that ghrelin reflects body condition and influences migratory behavior of wild birds. We measured ghrelin levels of wild garden warblers (Sylvia borin) captured at a stopover site. Further, we manipulated blood concentrations of ghrelin to test its effects on food intake and migratory restlessness. We found that acylated ghrelin concentrations of garden warblers with larger fat scores were higher than those of birds without fat stores. Further, injections of unacylated ghrelin decreased food intake and increased migratory restlessness. These results represent experimental evidence that appetite-regulating hormones control migratory behavior. Our study lays a milestone in migration physiology because it provides the missing link between ecologically dependent factors such as condition and timing of migration. In addition, it offers insights in the regulation of the hormonal system controlling food intake and energy stores in vertebrates, whose disruption causes eating disorders and obesity.

scholarly journals Ruff , Philomachus pugnax (Aves, Charadriiformes), Migration in Western Ukraine

2014 ◽  
Vol 48 (1) ◽  
pp. 75-82
Author(s):  
Iu. Strus
Keyword(s):  
Wing Length ◽  
Base Materials ◽  
Flight Range ◽  
Significant Difference ◽  
Philomachus Pugnax ◽  
Migration Dynamics ◽  
Western Ukraine ◽  
Juvenile Males ◽  
Second Wave ◽  
Made In

Abstract In the paper we discuss migration dynamics, biometry and stopover ecology of Ruff (Philomachus pugnax Linnaeus, 1758) in the Cholgini ornithological reserve. Also the observations, made in other regions of the western Ukraine, were used in the analysis. Th e base materials for this paper were collected during 1995-2012 by West-Ukrainian ornithological station, by conducting regular bird counts, ringing and taking measurements of migrating waders using standard methods. During Ruff spring migration two major waves of passage occured: the first one is from the end of March till early April and the second - from the end of April to the end of May. Th e average number of a flock was equal 12 individuals. In the autumn passage dynamics of two waves can also be seen. Th e fist wave is observed in July with the peak in the middle of month. Second wave occurs in August and in fist two decades of September, with maximum bird numbers in the end of August. Th e passage dynamic of Ruff in the Cholgini reserve is very similar to the dynamic in other continental staging sites. Significant difference was found in the wing length between the adult and juvenile Ruff s. Th e potential flight range of juvenile females was 3236 km, juvenile males - 2380 km, adult females - 2740 km.

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