scholarly journals Conditions at the breeding grounds and migration strategy shape different moult patterns of two populations of Eurasian golden plover Pluvialis apricaria

2018 ◽  
Vol 49 (9) ◽  
pp. e01709
Author(s):  
Paula Machín ◽  
Magdalena Remisiewicz ◽  
Juan Fernández-Elipe ◽  
Joop Jukema ◽  
Raymond H. G. Klaassen
Keyword(s):  
Migration Strategy ◽  
Breeding Grounds ◽  
And Migration ◽  
Golden Plover ◽  
Two Populations

Fat reserves and migration of Red-necked Phalaropes (Phalaropus lobatus) in the Quoddy region, New Brunswick, Canada

1985 ◽  
Vol 63 (12) ◽  
pp. 2810-2816 ◽  
Author(s):  
Francine M. Mercier
Keyword(s):  
New Brunswick ◽  
Fat Deposition ◽  
The Arctic ◽  
Bay Of Fundy ◽  
Migration Route ◽  
Migration Strategy ◽  
Wintering Grounds ◽  
Fat Reserves ◽  
Breeding Grounds ◽  
And Migration

Arrival, length of stay, fat deposition, flight range, and migration strategy of Red-necked Phalaropes (Phalaropus lobatus) were studied during the 1981–1982 autumn migrations through the Quoddy region, New Brunswick, Canada. Arrivals at this staging ground reflected the sequence in departures from the Arctic breeding grounds reported in the literature. Females arrived first, followed by males and finally juveniles, based on overall population composition during the season and patterns of fat deposition. Fat was deposited at the rate of 1.0 g per day over a period of about 20 days and maximum fat reserves amounted to between 40 and 45% of fresh weight, yielding enough for potential flight ranges of 4300–5100 km. The probable wintering grounds for the Quoddy region population are the waters off Peru, with the most direct migration route from the Bay of Fundy being some 6000 km long. This distance considerably exceeds the calculated nonstop flight capacities of Red-necked Phalaropes, and precludes their arriving at the wintering grounds without making another feeding stop, possibly off Panama.

scholarly journals Prevalence and genetic diversity of avian haemosporidian parasites in wild bird species of the order Columbiformes

2021 ◽  
Author(s):  
Yvonne R. Schumm ◽  
Dimitris Bakaloudis ◽  
Christos Barboutis ◽  
Jacopo G. Cecere ◽  
Cyril Eraud ◽  
...  
Keyword(s):  
Host Species ◽  
Large Scale ◽  
Phylogenetic Reconstruction ◽  
Bird Species ◽  
Avian Species ◽  
Blood Parasites ◽  
Migration Strategy ◽  
Haemosporidian Parasites ◽  
Multiplex Pcr Assay ◽  
And Migration

AbstractDiseases can play a role in species decline. Among them, haemosporidian parasites, vector-transmitted protozoan parasites, are known to constitute a risk for different avian species. However, the magnitude of haemosporidian infection in wild columbiform birds, including strongly decreasing European turtle doves, is largely unknown. We examined the prevalence and diversity of haemosporidian parasites Plasmodium, Leucocytozoon and subgenera Haemoproteus and Parahaemoproteus in six species of the order Columbiformes during breeding season and migration by applying nested PCR, one-step multiplex PCR assay and microscopy. We detected infections in 109 of the 259 screened individuals (42%), including 15 distinct haemosporidian mitochondrial cytochrome b lineages, representing five H. (Haemoproteus), two H. (Parahaemoproteus), five Leucocytozoon and three Plasmodium lineages. Five of these lineages have never been described before. We discriminated between single and mixed infections and determined host species-specific prevalence for each parasite genus. Observed differences among sampled host species are discussed with reference to behavioural characteristics, including nesting and migration strategy. Our results support previous suggestions that migratory birds have a higher prevalence and diversity of blood parasites than resident or short-distance migratory species. A phylogenetic reconstruction provided evidence for H. (Haemoproteus) as well as H. (Parahaemoproteus) infections in columbiform birds. Based on microscopic examination, we quantified parasitemia, indicating the probability of negative effects on the host. This study provides a large-scale baseline description of haemosporidian infections of wild birds belonging to the order Columbiformes sampled in the northern hemisphere. The results enable the monitoring of future changes in parasite transmission areas, distribution and diversity associated with global change, posing a potential risk for declining avian species as the European turtle dove.

scholarly journals Migratory Connectivity in Bicknell's Thrush: Locating Missing Populations With Hydrogen Isotopes

The Condor ◽  
2004 ◽  
Vol 106 (4) ◽  
pp. 905-909 ◽  
Author(s):  
Keith A. Hobson ◽  
Yves Aubry ◽  
Leonard I. Wassenaar
Keyword(s):  
North America ◽  
Dominican Republic ◽  
Migratory Birds ◽  
Geographical Information ◽  
Source Population ◽  
Catharus Bicknelli ◽  
Breeding Grounds ◽  
Early Fall ◽  
Bicknell's Thrush ◽  
Two Populations

Abstract The measurement of the abundance of naturally occurring deuterium (δD) in feathers grown in North America can provide geographical information on location where the feather was grown. Previously, we used this technique to link populations of Bicknell's Thrush (Catharus bicknelli) breeding in northeastern North America (to 46°N) with wintering grounds in the Dominican Republic. That study indicated the presence of a subpopulation of wintering birds with more depleted feather δD values than those measured on their known breeding grounds. This suggested either a more northerly or a higher altitude breeding source population than previously measured. We located two populations of Bicknell's Thrush in Quebec, Canada, at Mine Madeleine (49°N) and at Mont Gosford (45°N). The Mine Madeleine birds had feather δD values overlapping those of the unidentified subpopulation found wintering in the Dominican Republic. At Mont Gosford, hatch-year birds were more depleted in their feather δD values than after-second-year birds suggesting their more northerly origins and capture during the early fall migration period. Our study demonstrates how the stable-isotope approach can be used to document connectivity between breeding and wintering populations of migratory birds. Conectividad Migratoria en Catharus bicknelli: Localización de Poblaciones Perdidas con Isótopos de Hidrógeno Resumen. La medición de la abundancia de deuterio en estado natural (δD) en las plumas formadas en América del Norte puede brindar información geográ fica sobre la localización en donde se formó la pluma. Anteriormente usamos esta técnica para relacionar las poblaciones de Catharus bicknelli que se reproducen en el noreste de América del Norte (hasta 46°N) con las áreas de invernada en República Dominicana. Ese estudio indicó la presencia de una subpoblación de aves invernantes con valores de δD en las plumas por debajo de los valores medidos de los sitios conocidos de cría. Esto sugirió la presencia de una población reproductiva proveedora de individuos localizada más al norte o a mayor elevación que las registradas anteriormente. Localizamos dos poblaciones de C. bicknelli en Québec, Canadá, una en Mine Madeleine (49°N) y otra en Mont Gosford (45°N). Las aves de Mine Madeleine tuvieron valores de δD en las plumas que se superpusieron con aquellos de la subpoblación no identificada encontrada invernando en República Dominicana. En Mont Gosford, las aves del primer año de edad presentaron valores más bajos de δD en las plumas que aquellos encontrados en aves del segundo año de edad o mayores, sugiriendo un origen más boreal y que fueron capturadas durante el inicio del período de migración otoñal. Nuestro estudio demuestra como el mé todo de isótopos estables puede ser usado para documentar conectividad entre poblaciones reproductivas e invernales de aves migratorias.

scholarly journals Optimal Scheduling of a Microgrid Using Multiobjective Biogeography-Based Optimization Model and Algorithm with Adaptive Migration

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Bo Li ◽  
Jue Wang ◽  
Nan Xia
Keyword(s):  
Pareto Frontier ◽  
Evolutionary Model ◽  
Optimal Scheduling ◽  
Constraint Handling ◽  
Migration Strategy ◽  
Suitability Index ◽  
Proposed Model ◽  
Convergence Performance ◽  
Distribution Uniformity ◽  
And Migration

Aiming at the important research topic of optimal scheduling in the microgrid field, the general model for multiobjective dynamic optimal scheduling of a microgrid is established with the objective of minimizing economic and environmental costs. On this basis, the model is organically integrated with constraint handling technology, multiobjective optimization, and biogeography-based optimization algorithm, and then a constrained multiobjective evolutionary model suitable for biogeography-based optimization is further established. The corresponding constraint handling mechanism, the determination method of habitat suitability index, and migration strategy are improved, and the convergence performance and the distribution uniformity of Pareto frontier for multiobjective evolutionary algorithm are effectively enhanced. Applied to the optimal scheduling of typical microgrid systems, the effectiveness of the proposed model and method is verified.

scholarly journals Historical and current distribution, population size and possible migration routes of the Blue Swallow Hirundo atrocaerulea in Africa

2010 ◽  
Vol 20 (3) ◽  
pp. 240-254 ◽  
Author(s):  
STEVEN W. EVANS ◽  
H. BOUWMAN
Keyword(s):  
Population Size ◽  
Democratic Republic ◽  
Sub Saharan Africa ◽  
Total Current ◽  
Migration Routes ◽  
Breeding Grounds ◽  
Republic Of The Congo ◽  
Migratory Routes ◽  
Sub Saharan ◽  
And Migration

SummaryThe Blue Swallow Hirundo atrocaerulea is restricted to sub-Saharan Africa, its population size previously estimated at fewer than 1,500 pairs, and is classified as Vulnerable. A better understanding of its current distributional range, population size, protection status and migration routes would improve our ability to conserve the species and the grassland and wetland habitat on which it depends. We now estimate that the Blue Swallow population in the 1850s may have numbered between 1,560 and 2,300 pairs. Based on an assessment of available data, we now estimate the total current Blue Swallow population at 1,006 pairs or 2,012 individuals, an estimated 36–56% decline over the last 150 years. There may be three separate Blue Swallow sub-populations and seven separate migratory routes between their breeding and non-breeding grounds. The Blue Swallow’s range in South Africa and Swaziland has contracted by 74%. The majority of Blue Swallows occupy unprotected areas on their non-breeding grounds in the Democratic Republic of the Congo, Uganda and Kenya. The Blue Swallow population in Africa will continue to decline unless the causes of reduction in Blue Swallow habitat quantity and quality can be stopped and sufficient and additional habitat set aside to sustain viable Blue Swallow populations throughout their range.

A replication and migration strategy on the hierarchical architecture in the fog computing environment

2020 ◽  
Vol 16 (3) ◽  
pp. 291-307
Author(s):  
Ahmed Berkennou ◽  
Ghalem Belalem ◽  
Said Limam
Keyword(s):  
Fog Computing ◽  
Hierarchical Architecture ◽  
Computing Environment ◽  
Huge Amount ◽  
Migration Strategy ◽  
Replication Strategy ◽  
Promising Solution ◽  
Network Usage ◽  
And Migration ◽  
Do So

Connecting objects have increasingly become popular in recent years, leading to the connection of more than 50 billion objects by the end of 2020. This large number of objects will generate a huge amount of data that is currently being processed and stored in the cloud. Fog Computing presents a promising solution to the problems of high latency and huge network traffic encountered in the cloud. As Fog’s infrastructures are dense, heterogeneous and geo-distributed, managing the data in order to satisfy users demand in such context is very complicated. In this work, we propose a data management strategy called ‘RMS-HaFC’ in which we consider the characteristics of Fog Computing environment. To do so, we proposed a hierarchical multi-layer model, on which we designed a migration and replication strategy based on data popularity. These strategies duplicate files dynamically and store them in different locations to improve the response time of users requests and minimize the system energy consumption without loading network usage. The strategy was evaluated using the iFogSim simulator and the experimental results obtained are very promising.

scholarly journals Evolution of moult-migration is directly linked to aridity of the breeding grounds in North American passerines

2020 ◽  
Vol 16 (6) ◽  
pp. 20200155
Author(s):  
Claudie Pageau ◽  
Christopher M. Tonra ◽  
Mateen Shaikh ◽  
Nancy J. Flood ◽  
Matthew W. Reudink
Keyword(s):  
North American ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Autumn Migration ◽  
Western North America ◽  
Migration Distance ◽  
Migration Strategy ◽  
Breeding Grounds ◽  
Breeding Migration ◽  
Moult Migration

To avoid energy allocation conflicts, birds generally separate breeding, migration and moult during the annual cycle. North American passerines typically moult on the breeding grounds prior to autumn migration. However, some have evolved a moult-migration strategy in which they delay moult until stopping over during autumn migration. Rohwer et al . (2005) proposed the ‘push–pull hypothesis' as an explanation for the evolution of this moult strategy, but it has not been empirically tested. Poor conditions on the breeding grounds at the end of the summer would push birds to depart prior to moult, while productive stopover locations would pull them. We tested for a relationship between moult-migration and breeding grounds aridity as measured by the normalized difference vegetation index. Our results strongly support the ‘push' aspect of the push–pull hypothesis and indicate that arid breeding grounds, primarily in western North America, would drive species to evolve stopover moult-migration, although this relationship may depend upon migration distance.

Ada-Things: An adaptive virtual machine monitoring and migration strategy for internet of things applications

2019 ◽  
Vol 132 ◽  
pp. 164-176 ◽  
Author(s):  
Zhong Wang ◽  
Daniel Sun ◽  
Guangtao Xue ◽  
Shiyou Qian ◽  
Guoqiang Li ◽  
...  
Keyword(s):  
Internet Of Things ◽  
Virtual Machine ◽  
Migration Strategy ◽  
Machine Monitoring ◽  
And Migration

scholarly journals Migration strategy predicts stopover ecology in shorebirds on the northern Gulf of Mexico

2015 ◽  
Vol 2 (1) ◽  
pp. 63-75 ◽  
Author(s):  
Jessica Renee Henkel ◽  
Caz M. Taylor
Keyword(s):  
Gulf Of Mexico ◽  
Population Level ◽  
Migration Strategy ◽  
Northern Gulf Of Mexico ◽  
Migratory Shorebirds ◽  
Breeding Grounds ◽  
Intermediate Distance ◽  
Potential Population ◽  
Conservation Plans ◽  
Plasma Metabolite

AbstractTwenty-eight species of migratory shorebirds rely on the coastlines of the northern Gulf of Mexico (NGOM) to fuel migrations to near-arctic breeding grounds. Shorebird species vary in their migration ecology: some species use a “jump” strategy, migrating long distances without stopping, while others use “skip” and “hop” strategies, stopping to refuel at shorter intervals along their journey. We compared stopover duration, body condition (fat scores and size-adjusted mass), and refueling rates (plasma metabolite concentrations), in three Calidrid sandpiper species (Calidris pusilla, C. mauri, and C. alpina) that differ in migration strategy after leaving the NGOM during spring. Results indicate that, while birds refueled at similar rates, C. alpina, an intermediate distance jump migrant, reached higher fuel stores before departing on migration than the hop and skip migrants, C. pusilla and C. mauri. C. alpina also spent more time on the NGOM than the other two species. Results suggest that NGOM habitats may be particularly important for migration success in C. alpina. This knowledge will help us predict the potential population level consequences of habitat loss due to global change on NGOM shorebird populations and develop conservation plans to mitigate these impacts.

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