Top PDF Spring migration of Black-tailed Godwits in Iberia 2017

Spring migration of Black-tailed Godwits in Iberia 2017

Spring migration of Black-tailed Godwits in Iberia 2017

67 Extremadura Team 1: Mo Verhoeven, Jelle Loonstra, 朱冰润 Drew Bingrun, 28-1 to 3-2-2017 Unfortunately no daily report available, but the table below gives an idea of the areas visited and numbers encountered; 115 resightings and 27 colour ring density-samples were recorded.

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High migratory survival and highly variable migratory behavior in black-tailed godwits

High migratory survival and highly variable migratory behavior in black-tailed godwits

This high degree of individual-level flexibility and population- level variability could mean that godwits are better able to respond to environmental change than other long-distance migrants. For instance, unlike Hudsonian and bar-tailed godwits ( Conklin et al., 2010; Senner et al., 2017 ), black-tailed godwits do not appear to be time constrained during their northward migration. This means that the fitness benefits for an individual of flexibly altering its migration timing, as well as the number of stops it makes during migration, may outweigh those of arriving at a specific site at a specific time. In turn, this may enable them to minimize the initiation of reversible state effects that carry-over the conditions experienced during previous time periods, potentially affecting their survival and fitness (sensu Senner et al., 2015c ). Accordingly, we have previously shown that many godwits delayed their migrations by arriving more than 20 days later than normal to their breeding sites in response to an early spring snowstorm in northwest Europe, enabling individuals that delayed their migrations to avoid the most inclement storm-related conditions, but also subsequently achieve high reproductive success ( Senner et al., 2015a ).
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Adverse wind conditions during northward Sahara crossings increase the in-flight mortality of Black-tailed Godwits

Adverse wind conditions during northward Sahara crossings increase the in-flight mortality of Black-tailed Godwits

Wind conditions and global climate change Increasing global temperatures are projected to cause signifi- cant changes to the distribution and viability of the popula- tions of many migratory bird species (Saino et al. 2010). However, relatively little attention has been paid to the pre- dicted changes in atmospheric circulations and their potential effects on the viability of migration itself (IPCC & Climate change 2013, but see: Weimerskirch et al. 2012, La Sorte & Fink 2017, La Sorte et al. 2019). Those investigations that have been undertaken suggest that wind conditions are expected to change as a result of climate change, at least in North and South America (La Sorte & Fink 2017; La Sorte et al. 2019), and that the strength of the wind and frequency of storms will increase in the Sahara region (Taylor et al. 2017), but the exact effect of these changing wind conditions on trans-Saharan migrants is largely unknown. Given our findings, which reveal a relationship between experienced wind conditions during migration and the survival of a trans-Saha- ran migrant, future studies should aim to understand how changing climatic conditions will affect the wind support of trans-Saharan migrants and, potentially, their population dynamics.
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Post-breeding migration of Dutch-breeding black-tailed godwits:Timing, routes, use of stopovers, and nonbreeding destinations

Post-breeding migration of Dutch-breeding black-tailed godwits:Timing, routes, use of stopovers, and nonbreeding destinations

Regardless of what created them, three distinct migration patterns are apparent among Dutch-breeding godwits and this complicates an already difficult and deteriorating conservation scenario. Agricultural inten- sification in Dutch meadows has been widely identified as playing a significant role in the reduction of breeding success and overall population declines in Dutch-breed- ing Black-tailed Godwits (Kentie et al. 2013). It also could play a significant, but as yet unknown, role in the ability of adults to obtain sufficient fuel resources before their southward migration given their apparent use of agricultural habitats during this period (Piersma et al. unpubl. data). The extent of available habitat at major spring stopover sites in France has declined in recent years – one of the two sites used by individuals in this study (Baie de l’Aiguillon, France) has lost more than 50% of its wet grasslands to the cultivation of corn – and when combined with continued late-summer hunting pressure may mean that these sites do not provide sufficient resources for adult godwits during this period (Kuijper et al. 2006). Coastal sites in Spain, Portugal, and Morocco are facing similar fates as more and more freshwater is diverted to agriculture, reduc- ing both overall habitat quantity and quality, as the freshwater wetlands required by L. l. limosa are turned brackish (Kuijper et al. 2006). Inland sites, such as the rice fields of Extremadura, Spain, and the estuarine ricefields of the Sado and Tejo rivers, Portugal, are currently more stable and artificially maintained (Lourenço & Piersma 2009). However pressure from illegal hunting, potential changes in agricultural prac- tices, and the lack of alternatives makes reliance on these sites unsatisfactory in the long-term (Lourenço & Piersma 2009, N.R. Senner pers. obs.). Finally, the rice fields and wetlands in West Africa that provide winter- ing habitat for the majority of Dutch-breeding godwits are changing. Coastal rice fields and natural wetlands in the Senegal River Delta – which were used by 10 of the 13 godwits that spent the winter in West Africa in this study – have been reduced in size by more than half since the 1980s (Wymenga & Zwarts 2010).
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Variation from an unknown source: large inter-individual differences in migrating black-tailed godwits

Variation from an unknown source: large inter-individual differences in migrating black-tailed godwits

the largest difference between the crossings of each individual over the course of the time that they were tracked. Next, we calculated the mean and standard deviation across all individuals (Figures 2C,D) and used a GLM to test for differences in the amount of intra-individual variation among spatial boundaries. When differences among spatial boundaries were found, we used a Tukey post-hoc test with a 95% confidence level to establish how the timing differed between pairs of boundaries. Additionally, we calculated the repeatability of each barrier crossing during south- and northward migration (Figures 2E,F). We did this by including individual as a random effect in the linear mixed model method of the function “rpt,” which is part of the R package “rptR” ( Stoffel et al., 2017 ). To evaluate whether individuals consistently shifted their timing earlier or later over the course of our study, we plotted for every spatial boundary the first observed timing of crossing vs. the last observed timing of crossing for each individual godwit (Figure S1).
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Habitat use and observations of Black-tailed Godwits between the Saloum and Senegal river delta’s

Habitat use and observations of Black-tailed Godwits between the Saloum and Senegal river delta’s

In 1983-1984 the wintering sites of godwits were explored for the first time. At that moment most godwits were wintering in rice areas along the West-African coast in Senegal, Gambia, Guinea-Bissau, Guinea and Sierra Leone. Big numbers of godwits also occurred in the inner Niger delta in Mali (Altenburg & van der Kamp 1985), but they probably belong to the eastern European population. Recently, the wintering behaviour has partly changed with an increasing number of godwits deciding to winter in South-Spain at National Park Doñana. In the 1980s during the first counts only 4% of the NW-European population used this area as a wintering site but recent estimations suggest a big change with up to 23% of the population wintering in Spain. The most important reason for this is probably the creation of new artificial fishponds and rice fields. It is remarkable that this increase is not driven by climatic changes in the Sahel zone of West-Africa (Márquez-Ferrando et al. 2013). For godwits, staying Iberia can be advantageous because they can skip a 3000 kilometre (v.v.) travel over the Sahara, a potentially dangerous migration route and save their fat stores for the next breeding season.
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Why should Black-tailed Godwits still winter in West-Africa if Southern Iberia is just as good?

Why should Black-tailed Godwits still winter in West-Africa if Southern Iberia is just as good?

this comparison. This means that by the end of 2015 at the earliest we might get a first hint of potential differences between the two wintering strategies and the consequences for the population. We have seen wintering godwits from Mauritania to Guinea Bissau and the fact that they occur spread out over big parts of West-Africa is already a clear indication of their flexibility. In the north they mainly use natural habitats in the floodplains of the Senegal and Saloum delta; these can vary from fairly freshwater to extremely salty. During the present survey we hardly saw any godwits in ricefields, but that might very well be due to the fact that the harvest had not started yet. It is hard to imagine that they will not use these fields especially since the timing of the harvest coincides perfectly with their northward migration in December. If so, they might even profit from the large-scale turnover of dry Sahel vegetation into irrigated ricefields, which is eminent all along the southern borders of the Djoudj NP. A striking parallel development has taken place in the floodplains of the Rio Guadalquivir in Spain which is now the alternative wintering location and important for many waterbird species: Donana NP! A point of concern is the invasive growth of Typha in large parts of the Senegal delta. This species might potentially make large areas of godwit-habitat unusable. Nevertheless, it would require detailed work on intake rates and daily time budgets to be see whether the great flexibility demonstrated by the godwits reflects easy or difficult living conditions. Other studies have shown that animal preys are preferred over a vegetarian diet and eating grass tubers or seeds might very well indicate that they don´t have an appealing alternative.
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An Examination of Spring Migration Timing in Songbirds

An Examination of Spring Migration Timing in Songbirds

The sexual uniformity in migration speed in wood warblers is perplexing given the sexual dimorphism in arrival date. Condition upon arrival at the breeding grounds is generally assumed to be more important in females who must undergo the energetically-demanding process of egg-lying. However, the observed sexual uniformity in migration speed may indicate that males, like females, benefit from arriving on the breeding grounds in good physical condition. Remaining stores can act as a safety net in the case of inclement weather or unforeseen food shortages. Furthermore, if less time is spent foraging for survival, more time can be devoted to male reproductive activities such as territory establishment and defense, nest building, and sperm production (Smith and Moore 2003). If this hypothesis was correct, males might not benefit from sacrificing physiological condition for migration speed any more than would females. Therefore, they may employ an alternative method to get to the breeding grounds first, for example, by altering distance and/or onset of migration. The fact that females arrive before males in species displaying “reverse” sexual dimorphism suggests that intrasexual competition for mates and/or territories, rather than resource constraints associated with egg-laying, is the driving force in the evolution of migratory timing. In both Red-necked ( Phalaropus lobatus ) and Wilson’s Phalaropes ( Phalaropus tricolor ), females compete vigorously for access to males. Reynolds et al. (1986) showed that females of both species preceded males to the breeding grounds, suggesting that in these species, females can increase their reproductive success more by getting their first and obtaining the best the best mate possible, than by delaying arrival to conserve resources for egg-laying.
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Spring budget 2017

Spring budget 2017

This document provides details of sources of data in all the tables, charts, and graphs in the Spring Budget 2017 document. In addition, it includes details of sources for some data included in the text where, for reasons of space, it has not been possible to footnote these sources. The document is aimed at transparently informing readers of the Spring Budget 2017 document where the data used in the charts, tables, and text comes from and how it has been calculated. This document also ensures that the Treasury meets the standards set out by the UK Statistics Authority to comply with the Statistics and Registration Service Act 2007. In particular, this document aims to meet 2 of the requirements of the UK Statistics Authority’s ‘Code of Practice for Official Statistics’:
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Research update, Spring 2017

Research update, Spring 2017

Estimating the macroeconomic effects of the ECB’s unconventional monetary policies is a complex exercise. There is no precedent for the extent to which central banks have used non-standard instruments since the onset of the financial crisis in 2007, which means that the empirical analysis must be concentrated on a relatively short period. An added difficulty is the wide range of non-standard measures that the ECB has used in the various phases of the crisis. We use a combination of sign restrictions and zero restrictions on the impulse responses to identify UMP shocks. In line with the most recent literature, the model uses the change in the Eurosystem balance sheet as a variable to capture the interventions of the monetary authority. Concretely, following the approach of Boeckx et al. (2017), non-standard monetary policy decisions are identified by two restrictions. First, they should represent exogenous balance sheet expansions: that is, expansions that are not responses to heightened financial stress. Second, they should reduce the spread between short-term interbank rates and the interest rate on the main refinancing operations. The first condition excludes changes in the ECB’s balance sheet that arise from banking system liquidity requirements in
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Spring 2017 Undergraduate Courses

Spring 2017 Undergraduate Courses

In this course we will look at key texts in the west that have contributed religious and theological ways of thinking about economics.. Questions discussed will consider t[r]

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Afterschool Matters, Spring 2017

Afterschool Matters, Spring 2017

She is a fellow of the International Society for Design and Development in Education (ISDDE). SCHUNN , PhD, is professor of psychology and senior scientist at the University of Pittsb[r]

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Diet of Black-Tailed Jackrabbits on Sandhill Rangeland in Colorado.

Diet of Black-Tailed Jackrabbits on Sandhill Rangeland in Colorado.

Forbs were more highly preferred than were grasses, and seasonally important foods received higher preference indices than those plants eaten in all seasons.. Becau[r]

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2017 Spring Commencement

2017 Spring Commencement

Dr. Kathy Thornton, Associate Professor of Nursing, is retiring July 31, 2017. Dr. Thornton earned her A.D.N. (1978) from Barton County Community College and her B.S.N. (1982) from Fort Hays State University. She received both her Master of Nursing (1988) and Ph.D. in Nursing (2000) from the University of Kansas. At the time of her retirement, she will have provided over 16 years of dis- tinguished service to Georgia Southern University and over 33 years to the academy overall. Dr. Thornton joined the faculty at Georgia Southern University as an assistant professor in 2001 and was pro- moted to associate professor in 2007. For the past six years, she served as program director of the fully online RN-BSN program. Her nursing expertise includes pediatric and perioperative nursing, and her research foci have included: effects of exercise metabolism and eating behaviors on weight loss; health risk for college students and for the university workforce (faculty and staff); and the impact of opioid use for chronic pain management. Dr. Thornton has dem- onstrated her scholarly activity through peer reviewed publications and regional and national presentations, and as a leader or par- ticipant in several research grants. She also served as a mentor and committee chair for numerous master’s level research projects and doctoral level clinical scholarly projects. Dr. Thornton has a strong record of service to the University, receiving the College of Health and Human Sciences Excellence in Service Award twice. She also received the College of Health and Human Sciences Excellence in Teaching Award. For all of her distinguished contributions to the school, college, University, and profession—too numerous to enu- merate here, Dr. Kathy Thornton deserves the title of Associate Professor Emerita of Nursing.
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Spring budget 2017

Spring budget 2017

 ‘removal of the spare room subsidy: legal challenge’ – the removal of the spare room subsidy, more commonly known as the ‘bedroom tax’, was the June 2010 measure ‘Social sector: limit working age entitlements to reflect size of family from 2013-14’ and has been in effect since April 2013. It reduces housing benefit and universal credit payments from claimants that have one or more spare rooms. In November 2016 DWP lost two legal challenges that will result, from April 2017, in one additional room being allowed in the entitlement calculations for certain claimants – where a couple are unable to share a room due to disability, or where a disabled child or non- dependent adult requires and has a non-resident overnight carer. This increases spending by around £70 million a year; and
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Spring-2017-Final-Draft.pdf

Spring-2017-Final-Draft.pdf

CHAD BRYANT (Associate Profes- sor, History) has been invited to be a visiting scholar at the University of Bremen’s Institute for History this summer. His forthcoming article “War as Revolution of the Self: The Diaries of Vojtěch Berger” will ap- pear in the spring 2017 issue of Střed, Centre. Časopis pro mezioborová stu- dia Střední Evropy 19. a 20. století. LOUISE McREYNOLDS (Distin- guished Professor, History) published “Nikolai Marr: Reconstructing Ani as the Imperial Ideal,” in Ab Imperio. In September 2016, she presented at the European Association of Archeolo- gists Conference in Vilnius and in Oc- tober gave a paper in Vancouver at the “Crime and Punishment at 150” Con- ference. In January 2017, she spoke on “The Vilnius Archaeological Congress of 1893” at the annual meeting of the American Historical Association and in March at the University of Texas at Austin about: “Hit ‘Refresh’ Before ‘Retire’: How Digital Humanities Re- newed My Pedagogy and Research.” DONALD J. RALEIGH (Distin- guished Professor, History) pub- lished “”Soviet” Man of Peace: Leo- nid Il’ich Brezhnev and His Diaries” in Kritika: Explorations in Russian
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Spring budget 2017

Spring budget 2017

policy announced as part of the Spring Budget only takes into account the estimated impact for new births and excludes the marginal impact in UC. The use of two different models, DWP’s PSM and HMT’s IGOTM, also means that the underlying household data is inconsistent. Each model will have different cut-off points for boundaries between income deciles, and interactions between tax and welfare measures are not fully captured. To address such issues HMT is

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Spring budget 2017

Spring budget 2017

1.28 The OBR forecasts that CPI inflation will increase to 2.4% in 2017 before falling back to 2.3% in 2018 and 2.0% from 2019 to 2021. Sterling has appreciated 3.3% on a trade-weighted basis since the beginning of November 2016, but remains 11.9% below its level of early June 2016, while global oil prices have increased 16.3% since the beginning of November. The two effects broadly counterbalance each other. Combined with the OBR’s judgement on the effect of policy measures, this means that inflation is expected to be slightly higher in the near term and slightly lower in later years than forecast at Autumn Statement 2016.
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Southeast Ohio Winter/Spring 2017

Southeast Ohio Winter/Spring 2017

But on this morning, the reenactors of the Battle of Buffington Island were merely “blowing off some powder.” The men of the 45th Ohio were just a handful of the about 250 participant[r]

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Individual fitness correlates in the Black-tailed Godwit. Julia Schroeder

Individual fitness correlates in the Black-tailed Godwit. Julia Schroeder

However, our interpretation hinges on the assumption that habitat quality in terms of food availability for adults is relatively high, and that adult food-related differences between territories have little biological meaning. One could also think of the possi- bility that areas where godwits breed in higher densities are of considerably high quality and can harbor a much larger number of godwits than areas with solitary nests. If this would be true, we cannot explain why more ornamented godwits would not breed in these high quality areas, too. The assumption that agricultural areas provide ample food supply for adults as opposed to the natural breeding habitat of godwits, marshes and bogs was made before (Bijsma et al., 2001; Zwarts et al., 2009). After moving the breeding habitat from natural areas into the agricultural grassland, godwits and other meadowbirds that relied on similar food experienced a considerable population increase, which is usually explained by the better food availability (Beintema et al., 1995; Bijlsma et al., 2001; Zwarts et al., 2009). Second, experimental studies have shown that an increase in food availability can enable birds to lay their eggs earlier in the season (see review by Meijer & Drent, 1999). When the usage of soil fertilizer increased during the last half of the last century, many meadowbirds including black-tailed godwits, shifted their laying date forward (Beintema et al., 1985). It was suggested that a nitrogen-related increase in food availability enabled black- tailed godwits to lay their clutches two weeks earlier (Beintema et al., 1985; Zwarts et al., 2009). This leads us to believe that it is valid to assume that food availability for adult godwits in agricultural grasslands is not a constraining factor for the choice of a nesting site.
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