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Autumn Migration Dynamics, Body Mass, Fat Load and Stopover Behaviour of the Willow Warbler (Phylloscopus trochilus) at Manyas KuşcennetI National Park (NW Turkey)

Autumn Migration Dynamics, Body Mass, Fat Load and Stopover Behaviour of the Willow Warbler (Phylloscopus trochilus) at Manyas KuşcennetI National Park (NW Turkey)

Turkey is located on one of the major migratory routes between Palearctic and Afrotropical regions. Despite its importance for many species, few studies exist on bird migration over Turkey. In this study, autumn migration dynamics and stopover behaviour of the Willow Warbler, a passage migrant in Turkey, was documented and analysed at Manyas Kuşcenneti National Park (NW Turkey). Birds were mist-netted, ringed, measured, weighed and fat scored from mid-August in 2002 and end of August in 2003 to end of October in both years. Totally, 543 and 929 Willow Warblers were ringed in 2002 and 2003, respectively. For 2002 and 2003 respectively, fat score values (mean ± SE) were 4.63 ± 0.06 and 3.84 ± 0.05, while body mass reached 11.38 ± 0.07 and 10.37 ± 0.05 g for birds captured for the first time. Fat scores in 2003 showed a bimodal distribution with peaks of T2 and T5, indicating populations or groups with different migratory strategies. The number of retraps constituted 9.2-12.1% of birds captured. In both years, minimum stopover length ranged from 1 to 15 or 16 days with a median of 5 days (averages 5.26 and 5.54, respectively). The majority of the retraps put on significant fat in both years. Retraps continued to put on weight for up to two weeks after they had arrived. In this second study documenting the Willow Warbler migration in Turkey, it was revealed that such wetlands as Manyas Kuşcenneti National Park provide crucial stopover habitat for possibly several populations of the species enabling them to gain necessary fat loads before crossing two major ecological barriers, the Mediterranean Sea and the Sahara.

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

Abstract

Kováts D. 2012. Autumn migration of the Thrush Nightingale (Luscinia luscinia) in northern Hungary. 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.

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Development of Evaluation System of Coastline Resource in Dafeng

Abstract

Coastline is one type of valuable non-renewable resources. From the perspective of economic theory, it can gather population, promote traffic construction, and then improve the level of international trade. The research object of this paper is the coastline resource in Dafeng area. Firstly, we have a brief summary of the existing coastline evaluation literature, then introduce the location and natural attributes of the coastline resources in Dafeng. Following that, the Analytic Hierarchy Process (AHP) model is used to build the economic evaluation index system based on the characteristics of coastline in Dafeng. Specially, this index system consists of 6 factors, and a total of 41 detailed indicators were chosen including water depth, GDP, etc. On this basis, we use the assignment method to quantify the weight of each index, and calculate the comprehensive score of coastline resource by using the YAAHP software. The final conclusion is as follows: The total score of economic evaluation of coastline resource in Dafeng is 0.87. Therefore, the coastline resource in Dafeng will eventually be constructed a unique coastal economic zone, where the implemented port industrial projects will include shipbuilding, logistics, mechanical processing etc.

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Variation in body mass and fat reserves of the Sedge Warbler Acrocephalus schoenobaenus on autumn migration in the L'viv province (W Ukraine)

Variation in body mass and fat reserves of the Sedge Warbler Acrocephalus schoenobaenus on autumn migration in the L'viv province (W Ukraine)

The aim of the paper is limited to a rough describing peculiarities of relations between fat deposit level and the body mass as well as a seasonal and diurnal dynamics of catching at an inland study site located far to the North from important geographical barriers on the Sedge Warbler migration to Central Africa. Material was collected in 1999 and 2000 from July (11 Jul. 1999 and 28 Jul. 2000) till 29 August in L'viv province (western Ukraine). In the present paper 1066 Sedge Warblers caught in 1999 and 407 ones caught in 2000 were taken under consideration. Their body mass and fat score were recorded according to rules published by Busse (1983, 2000). During elaboration of the data the idea of body mass standardisation for a defined fat score (T 2) was adopted (Busse 1970) and adequate correction values (ci) were calculated. Because of the obtained results a new procedure of the correction values defining - if the data allow - is proposed.

In both years adults were highly significantly heavier than immatures. This finding leads to conclusion that summarising data for adult and immature Sedge Warblers in calculation of body mass correction values would result in significant growth of variance. Having compared the body mass in years 1999 and 2000 a pronounced difference between immatures was found. In 1999 the first period of migration was characterised by relatively high representation of adults (16.8%) and a low fat level (average fat score T = 1.76 and relative fat load t = -0.12 g for adults, while T = 1.57 and t = -0.21 g for immatures). This time was probably premigration dispersion and gaining of fat before migration rather than real migration movements. The share of adults among Sedge Warblers migrating in second and third periods was very similar in both studied years (1999 - 9.43% and 2000 - 9.46%). The fat load of birds caught during these periods was higher than in the starting period but still rather low as for long-distance migrants (T = 2.06-2.42 and t = 0.03-0.21 g for adults, T = 1.90-2.30 and t = -0.05-0.16 g for immatures). Both the fat load and body mass was growing during a day. The most interesting here were the differences in the growth rate: the average fat load grew during a day by 0.27 g while direct values of the actual body mass differed by as much as 0.84 g (that is more than two times more). This relation was repeated in 2000. That could mean that visible fat deposit does not reflect all gained fuel, but it should be studied more deeply than even big samples, from two years only, allow.

Analysing changes of the fat load and the body mass one must keep in mind that observed differences in the fat scores of birds caught in different parts of a day could be caused by two separate processes: (1) feeding and accumulation of fuel reserves (passing borders set in a fat scoring procedure) and (2) possible differentiation of the diurnal activity of birds that already have different levels of stored fat.

Open access
A comparison of machine learning algorithms for the prediction of Hepatitis C NS3 protease cleavage sites

Abstract

Hepatitis is a global disease that is on the rise and is currently the cause of more deaths than the human immunodeficiency virus each year. As a result, there is an increasing need for antivirals. Previously, effective antivirals have been found in the form of substrate-mimetic antiviral protease inhibitors. The application of machine learning has been used to predict cleavage patterns of viral proteases to provide information for future drug design. This study has successfully applied and compared several machine learning algorithms to hepatitis C viral NS3 serine protease cleavage data. Results have found that differences in sequence-extraction methods can outweigh differences in algorithm choice. Models produced from pseudo-coded datasets all performed with high accuracy and outperformed models created with orthogonal-coded datasets. However, no single pseudo-model performed significantly better than any other. Evaluation of performance measures also show that the correct choice of model scoring system is essential for unbiased model assessment.

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Evaluations of port performances from a seaborne cargo supply chain perspective

Abstract

Previous research on port efficiency focuses primarily on the provider’s perspective and assumes that maximizing the output is always desirable. This paper recognizes that maximizing the final output does not necessarily guarantee an efficient system and the notion of port efficiency and service effectiveness needs to be considered from the perspectives of both the provider and the consumer of the port service. The paper proposes a network-DEA model to evaluate the performances of 30 seaports worldwide. The concurrent consideration of efficiency scores from the network-DEA model and the traditional DEA-CCR model will offer valuable insights to port operators on how to improve port performances as part of a seaborne cargo supply chain.

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Evaluation of the virulence of Sclerotium rolfsii isolates on Arachis hypogaea and screening for resistant genotypes in greenhouse conditions

Summary

Sclerotium rolfsii is a soil borne pathogen responsible for root and stem rot on a wide range of crops. This study was conducted to identify the virulence of different S. rolfsii isolates on a susceptible local peanut germplasm and determine the resistance of 20 peanut genotypes to the most virulent isolate and also the relationship between virulence and mycelial compatibility groups (MCGs). Seventy eight isolates of this fungus from 10 host plants and six known MCGs were used in the experiment. The experiment was done in greenhouse conditions (25±5°C) using a complete randomized block design with three replications. Pots containing sterile soil (pH=6.7) were inoculated with barley seeds colonized by each isolate separately before being seeded with the peanut germplasm. Disease severity was assessed by scoring the wilting, yellowing or death of plants, mycelia or sclerotia production on the soil surface or on plant stem, stem area affected (%) and stem lesion length, at the stage of plant maturity. Also, shoot wet weight and plant height were recorded at this stage. According to the results of the pathogenicity tests, all of the isolates were virulent on the susceptible peanut germplasm and the virulence diff ered signifi cantly between the isolates (P≤0.01). There was no relationship between the virulence of the five groups of isolates identified in the present study and the MCGs. The peanut genotype 140, which was better than the others based on seed size, plant height and the canopy size, was also the most resistant one

Open access
The Ringing Site In Jericho (Palestine) – Development Of Bird Migration And Parasitological Research On The Great Rift Valley Flyway

ABSTRACT

A new research project near Jericho in the Jordan Valley (Palestine) was launched on 10 September 2013, work continued until October 23rd 2013. Standard ornithological work and bird ringing work was conducted using mist nets situated in an oasis type habitat of Wadi Qelt surrounded by palm plantations. The field methods followed the SEEN (SE European Bird Migration Network) standards that include apart from ringing of captured birds, also several measurements (wing length, tail length, wing formula) and scores (fat load and body mass), as well as the studies on the directional preferences of migrants using round, flat orientation cages. Ornithological research was enhanced by parasitological studies analysing migratory birds (hosts) - helminths relations during migration period of the former. This was a part of complex studies covering the Middle East and north African ringing sites. Altogether 481 individuals of birds representing 59 species were ringed and about 50 were retrapped. The most interesting was relatively high share of Masked and Red-backed shrikes as well as good number of birds of local species as Dead Sea Sparrows and introduced Indian Silverbills.

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Jericho (Palestine) Spring 2014 Ornithological and Parasitological Research Results

Abstract

Work begun in autumn 2013 at a research ringing site near Jericho in the Jordan Valley (Palestine) was continued in spring 2014 (8 March–18 April). Due to a flood, the area was much changed in relation to the autumn habitat distribution. Standard ornithological and ringing work was performed using mist nets. The methods used were in accordance with SEEN (SE European Bird Migration Network) standards, and apart from ringing included some measurements (wing length, tail length, wing formula) and scores (fat determination and body mass), as well as testing of the directional preferences of migrants. The ornithological work was expanded to include parasitological testing, taking into account migrant-helminth relations during migration. Altogether 508 birds from 44 species were ringed and inspected for external signs of infection by Collyriclum faba trematodes (subcutaneous cysts), and an additional 32 dead individuals were collected and dissected. Altogether 168 internal parasites were found. The most common migrants in spring were Lesser Whitethroat Sylvia curruca, Blackcap Sylvia atricapilla and Olivaceous Warbler Hippolais pallida, while the autumn dominants–Masked and Red-backed shrikes (Lanius nubicus and L. collurio) were scarce. In spring a good number of Dead Sea Sparrows Passer moabiticus were caught, but only two introduced Indian Silverbills Lonchura malabarica.

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Stem cracks of Norway spruce (Picea abies (L.) Karst.) provenances in Western Latvia

Abstract

Stem cracks are damaging for timber quality and can reduce the monetary value of a tree both directly and indirectly: serving as gateway for fungal infections. Aim of the study was to assess the influence of tree dimensions and seed origin on the frequency of stem crack for Norway spruce. The study was carried out in two contiguous provenance trials (material from 12 countries), established in 1972 and 1975 in Western Latvia. Stem cracking was assessed using five-score scale. Most of the affected trees (90%) had very light or light damage. There was no relation of diameter at breast height to incidence of stem cracks. Analysis revealed a significant provenance effect on occurrence of stem cracks. Russian provenances tended to have lower risk of stem cracking and relatively narrow variation within the region, while Baltic and Ukrainian origins had wide range of stem cracking, having best as well as worst provenances in terms of cracking. Overall it is possible to select fast growing provenances with relatively low incidence of stem cracks.

Open access