scholarly journals Migration chronology of Eastern-Population Tundra Swans

2003 ◽  
Vol 81 (5) ◽  
pp. 861-870 ◽  
Author(s):  
S A Petrie ◽  
K L Wilcox

We used satellite platform transmitting transmitters (PTTs) in 1998–2000 to track spring and fall migratory movements of Tundra Swans (Cygnus columbianus columbianus) captured at Long Point, Ontario. Migration corridors reported here corroborated those identified in previous studies using alphanumerically coded neck collars. However, PTTs provided additional information on duration of spring and fall migrations, duration of stay in different staging regions, time spent on breeding and wintering areas, and migration speed. Birds migrated between the Atlantic coast and northern prairies along a narrow geographic corridor through portions of the southern Great Lakes. From the northern prairies, swans followed 3 corridors to breeding areas on the west coast of Hudson Bay, central High Arctic, and Mackenzie River delta. While swans spent considerable time on Great Lakes (27% of spring migration) and northern prairie (40%) staging areas in spring, the northern boreal forest was an important fall staging area (48% of fall migration). Tundra Swans spent 20% of the annual cycle on wintering areas, 28% on spring staging areas, 29% on breeding areas, and 23% on fall staging areas. The long duration of migration and the fact that birds spend half their lives on staging areas underscore the importance of conserving Tundra Swan migratory habitats. Thirty-gram neck-collar-attached PTTs were more suitable than 95-g Teflon-harness-attached backpack PTTs for tracking Tundra Swans.

1992 ◽  
Vol 70 (10) ◽  
pp. 2021-2027 ◽  
Author(s):  
Jay B. Hestbeck ◽  
James D. Nichols ◽  
James E. Hines

Predictions of the time-allocation hypothesis were tested with several a posteriori analyses of banding data for the mallard (Anas platyrhynchos). The time-allocation hypothesis states that the critical difference between resident and migrant birds is their allocation of time to reproduction on the breeding grounds and survival on the nonbreeding grounds. Residents have higher reproduction and migrants have higher survival. Survival and recovery rates were estimated by standard band-recovery methods for banding reference areas in the central United States and central Canada. A production-rate index was computed for each reference area with data from the U.S. Fish and Wildlife Service May Breeding Population Survey and July Production Survey. An analysis of covariance was used to test for the effects of migration distance and time period (decade) on survival, recovery, and production rates. Differences in migration chronology were tested by comparing direct-recovery distributions for different populations during the fall migration. Differences in winter locations were tested by comparing distributions of direct recoveries reported during December and January. A strong positive relationship was found between survival rate and migration distance for 3 of the 4 age and sex classes. A weak negative relationship was found between recovery rate and migration distance. No relationship was found between production rate and migration distance. During the fall migration, birds from the northern breeding populations were located north of birds from the southern breeding populations. No pattern could be found in the relative locations of breeding and wintering areas. Although our finding that survival rate increased with migration distance was consistent with the time-allocation hypothesis, our results on migration chronology and location of wintering areas were not consistent with the mechanism underlying the time-allocation hypothesis. Neither this analysis nor other recent studies of life-history characteristics of migratory and resident birds supported the time-allocation hypothesis.


PLoS ONE ◽  
2021 ◽  
Vol 16 (5) ◽  
pp. e0252055
Author(s):  
Kurt K. Burnham ◽  
Jennifer L. Burnham ◽  
Jeff A. Johnson ◽  
Abby Huffman

Although the Atlantic puffin Fratercula arctica is well studied throughout its temperate and low Arctic breeding range, few have studied the species in its far northern distribution. This study is the first to present data on the migratory movements of the “large-billed” subspecies, F. a. naumanni, that breeds in the high Arctic and which has significantly larger body size than those farther south. During 2013–2015, migration tracks were collected from nine adult puffins (6 males and 3 females) tagged with geolocators in northwest Greenland. Overall, female puffins traveled farther than males on their annual migration, with one female puffin traveling over 13,600 km, which was nearly a third farther than any tagged male in our study. Differential migration was observed in migratory phenology and route, with males using a form of chain migration with acute synchrony between individuals while females appeared to largely use leap-frog migration and showed little synchrony between individuals. Extreme sexual segregation in wintering areas was evidenced by two females that migrated to the southern limit of the species’ range while the six males remained at the northern limit, and wintered along the sea ice edge during portions of the non-breeding season. Male puffins thus wintered in regions with sea surface temperatures up to 10° C cooler than female puffins, and in areas with generally colder sea surface temperatures when compared to previously known wintering areas of temperate and low Arctic puffin breeding populations. The degree to which body size enables male F. a. naumanni to remain in colder waters likely reflects differing life history constraints between sexes and populations (i.e., subspecies). Further study is warranted to investigate how recent changes in climate have further exacerbated the observed differences between sexes in high Arctic puffins and possibly other marine avian species.


Author(s):  
Jorge García-Macía ◽  
Javier Vidal-Mateo ◽  
Javier De La Puente ◽  
Ana Bermejo ◽  
Rainer Raab ◽  
...  

AbstractRed Kite shows a great variability in its migration strategies: most individuals in north-eastern Europe are migrants, but there is also a growing number of sedentary individuals. Here, we tagged 49 Red Kites wintering in Spain with GPS/satellite transmitters between 2013 and 2020 to study the autumn and spring migration between the breeding or summering areas in Central Europe and the wintering quarters in Spain. In first place, differences between immatures and adults were found for spring migration. Adults began the spring migration towards the northeast in February–March while the immature individuals began to migrate significantly later and showing a wider date range (February-June). Adults also takes significantly less days to arrive at their destinations (12 ± 5 days) and cover more distance per day (134.2 ± 37.1 km/day) than immatures (19 ± 11 days and 98.9 ± 21.2 km/day). In second place, we also found differences between spring and autumn migration (excluding immatures). Spring migrations were clearly faster and with less stopovers days than autumn migrations. Autumn migration began between mid-October and late November and two different behaviours were observed: most birds made a quick migration direct to the wintering areas with only some days of stopovers, but others prolonged the migration with long stops along the route. These results highlight a great variation in the migratory movements of Red Kite, not only according to age but also between individuals and seasons.


2007 ◽  
Vol 60 (1) ◽  
pp. 31-47 ◽  
Author(s):  
Brian Greenwood ◽  
Allana Permanand-Schwartz ◽  
Christopher A. Houser

Abstract Burley Beach (southeastern Lake Huron) exhibits a multi-barred shoreface, the long-term equilibrium morphology characteristic of many low angle, sandy beaches in the Canadian Great Lakes. During a single major storm, a new bar emerged 50-60 m offshore as an irregular trough-crest form, through differential erosion of an existing shore terrace. Emergence, bar growth and offshore migration were associated with: (a) an overall negative sediment balance in the inner surf zone initially (‑2.30 m3>/m beach width), but with a large positive sediment balance (+5.10 m3/m) subsequent to the storm peak and during the storm decay; (b) progradation of the beach step to produce a new shore terrace; and (c) offshore migration of the two outer bars to provide the accommodation space necessary for the new bar. The primary transport mechanisms accounting for emergence of the new bar, its growth and migration were: (a) the mean cross-shore currents (undertow), which always transported suspended sediment offshore; and (b) the onshore transport of suspended sediment by incident gravity wave frequencies early in the storm and subsequently by infragravity waves (at the storm peak and the decay period). The longshore transport of sediment was significant in terms of the gross transport, although the net result was only a small transport to the south-west (historic littoral transport direction). It did not cause bar initiation, but it may have supplied some of the sediment for bar growth. The primary mechanism for bar initiation and growth was the cross-shore displacement of sediment by wave-driven (oscillatory) transport and cross-shore mean currents (undertow).


2020 ◽  
pp. 089443932091831 ◽  
Author(s):  
Fabian Kalleitner ◽  
Monika Mühlböck ◽  
Bernhard Kittel

Traditional survey research faces declining response rates due to changing cultural habits and technological developments. Researchers have developed novel approaches to increase respondents’ likelihood of participating in web surveys. However, we lack information about whether these methods indeed increase response rates and, if so, whether they bias the resulting data. This article focuses on the use of nonmaterial incentives in the form of a video that provides the invitees with information tailored to their life situation. Analysis of our experimental data shows that instead of increasing respondents’ probability of starting the survey, the video treatments actually decrease it. We provide evidence that the lower salience of the intrinsic benefits of survey participation in the invitation email significantly contributes to this reduction. Additionally, the effect of the nonmaterial incentive differs across subgroups, affecting nonresponse biases in line with employment status, gender, and migration background. We therefore conclude that using additional information in the form of a video as a nonmaterial survey incentive is only suitable under specific conditions.


2019 ◽  
Vol 84 (4) ◽  
pp. 591-609 ◽  
Author(s):  
Matthew C. Sanger ◽  
Brian D. Padgett ◽  
Clark Spencer Larsen ◽  
Mark Hill ◽  
Gregory D. Lattanzi ◽  
...  

Analysis of human remains and a copper band found in the center of a Late Archaic (ca. 5000–3000 cal BP) shell ring demonstrate an exchange network between the Great Lakes and the coastal southeast United States. Similarities in mortuary practices suggest that the movement of objects between these two regions was more direct and unmediated than archaeologists previously assumed based on “down-the-line” models of exchange. These findings challenge prevalent notions that view preagricultural Native American communities as relatively isolated from one another and suggest instead that wide social networks spanned much of North America thousands of years before the advent of domestication.


1989 ◽  
Vol 104 (1) ◽  
pp. 313-322
Author(s):  
Giannina Poletto

AbstractAccording to one of the most popular classifications, solar flares may be assigned either to the category of small short-lived events, or to the category of large, long-duration two-ribbon (2-R) flares. Even if such a broad division oversimplifies the flare phenomenon, our knowledge of the characteristics of stellar flares is so poor, that it is worthwhile to investigate the possibility of adopting this classification scheme for stellar flares as well. In particular we will analyze Einstein observations of a long duration flare on EQ Peg to establish whether it might be considered as a stellar analogy of 2-R solar events. To this end we apply to EQ Peg data a reconnection model, developed originally for solar 2-R flares, and conclude that stellar observations are consistent with model predictions, although additional information is required to identify uniquely the physical parameters of the flare region. Application of the model to integrated observations of a 2-R solar flare, for which high spatial resolution data are also available, shows, however, that future integrated observations may allow us to solve the ambiguities of the model and use it as a diagnostic tool for a better understanding of stellar flares.


GeoTextos ◽  
2017 ◽  
Vol 13 (1) ◽  
Author(s):  
Ana Márcia Moreira Alvim ◽  
João Benvindo Amaral ◽  
Guilherme Luiz Lopes Ferreira

O estado do Tocantins atualmente é composto por 139 municípios que diferem quanto ao porte demográfico que varia em função do crescimento natural e da migração, processo que leva à redistribuição da população sobre o território. Por isso, tem-se por objetivo analisar os movimentos migratórios intermunicipais ocorridos no Tocantins entre 1991 e 2010. Os dados referentes à migração foram obtidos junto ao Instituto Brasileiro de Geografia e Estatística e extraídos utilizando-se o software estatístico SPSS. Com isso as matrizes de migração intermunicipal intraestadual foram geradas e os movimentos migratórios puderam ser analisados. O Tocantins, por se tratar de uma unidade da federação relativamente nova, tem sofrido mudanças que merecem ser consideradas pelas autoridades públicas. Constatou-se que embora o município de Palmas disponha de forte poder de atração, na mesorregião Oriental da qual faz parte, muitos municípios perdem população. Ao contrário, na mesorregião Ocidental, muitos ganham. Os movimentos mais intensos de longa distância ocorreram principalmente rumo à capital. Já os municípios mais antigos, Araguaína e Gurupi, atraíram maiores volumes de migrantes do entorno. Na mesorregião Oriental muitos municípios apresentam saldos migratórios negativos, sendo exportadores; enquanto na mesorregião Ocidental a maioria apresenta saldo migratóriopositivo, sendo atrativos à população tocantinense. Os movimentos ocorridos têm levado à maior concentração populacional no novo centro urbano – Palmas –, mas também naqueles que já dispunham de uma estrutura urbana diferenciada – como Araguaína e Gurupi –, o que merece maior atenção das autoridades públicas para que a concentração não se torne ainda maior. Ainda que Palmas tenha sido criada numa posição estratégica, a mesorregião a qual integra permanece contando com municípios cujas sedes não dispõem de estrutura urbana e dinamismo econômico capazes de mudar a realidade da região, e de seus respectivos municípios, cabendo ao governo pensar em estratégias para minimizar a concentração citada. Abstract INTERMUNICIPAL MIGRATORY MOVEMENTS IN THE STATE OF TOCANTINS (BRAZIL) BETWEEN 1991 AND 2010 The state of Tocantins currently consists of 139 municipalities that differ in demographic size, which varies according to natural growth and migration. Process leading to the redistribution of population over the territory. Therefore, the objective is to analyze the inter-municipal migratory movements that took place in Tocantins between 1991 and 2010. The migration data were obtained from the Brazilian Instituto Brasileiro from Geografia and Estatística – IBGE, and extracted using SPSS statistical software. In this way, the inter-state inter-municipal migration matrices were generated and the migratory movements could be analyzed. The Tocantins, because it is a relatively new unit of the federation, has undergone changes that deserve to be considered by the public authorities. It was found that although the municipality of Palmas has a strong attraction, in the eastern mesoregion of which it is a part, many municipalities lose population. On the contrary, in the Western mesoregion, many win. The more intense movements of long distance occurred mainly towards the capital. Already the older municipalities, Araguaína and Gurupi, attract larger volumes of migrants from the surrounding area. In the Eastern mesoregion, many municipalities present negative migratory balances, being exporters; While in the western mesoregion the majority have a positive migratory balance being attractive to the population tocantinense. The movements that have taken place have led to greater population concentration in the new urban center – Palmas – but also in those that already had a differentiated urban structure – such as Araguaína and Gurupi –, which deserves greater attention from the public authorities. Although Palmas was created in a strategic position, the mesoregion that it integrates continues counting on municipalities whose headquarters do not have urban structure and economic dynamism capable of changing the reality of the region, and of their respective municipalities, being the responsibility of the government to think in strategies for avoid the concentration.


2010 ◽  
Vol 50 (2) ◽  
pp. 729
Author(s):  
Keyu Liu ◽  
Peter Eadington ◽  
David Mills ◽  
Richard Kempton ◽  
Herbert Volk ◽  
...  

As part of a larger petroleum system analysis and resource re-evaluation research program in the Gippsland Basin, over 400 samples from 29 selected wells in the Gippsland Basin were investigated using quantitative fluorescence techniques developed by CSIRO Petroleum, including the quantitative grain fluorescence (QGF) and QGF on extracts (QGF-E) and the total scanning fluorescence (TSF) techniques. Preliminary results have provided new insight into the hydrocarbon migration and charge history of the Gippsland Basin. The investigation has revealed: widespread occurrence of palaeo oil columns in some of the major gas fields, indicating that a significant amount of oil was charged into these reservoirs prior to a subsequent gas accumulation; that some of the current oil intervals appear to have received a relatively late oil charge, either through new charge or through palaeo oil re-distribution due to adjustments within the petroleum system; palaeo oil columns appear to be restricted to a certain distance range from the major source kitchens; and, evidence of a sequential oil migration and displacement along structural highs where reservoirs distal to the source kitchens received progressively lighter and more mature palaeo oils. These findings are consistent with the oil generation and migration model proposed by O’Brien et al (2008). Fluid inclusion petrographic investigations and molecular composition of inclusions (MCI) analysis are currently underway that will provide additional information on the hydrocarbon charge history in the Gippsland Basin.


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