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Concept: Spoonbill

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Local recruitment and immigration play an important part in the dynamics and growth of animal populations. However, their estimation and incorporation into open populations models is, in most cases, problematic. We studied factors affecting the growth of a recently established colony of Eurasian spoonbill (Platalea leucorodia) and assessed the contribution of local recruits, i.e. birds born in the colony, and immigrants, i.e. birds of unknown origin, to colony growth. We applied an integrated population model that accounts for uncertainty in breeding state assignment and merges population surveys, local fecundity and individual longitudinal data of breeding and non-breeding birds, to estimate demographic rates and the relative role of recruitment and immigration in driving the local dynamics. We also used this analytical framework to assess the degree of support for the ‘performance-based’ and ‘conspecific attraction’ hypotheses as possible mechanisms of colony growth. Among the demographic rates, only immigration was positively and significantly correlated with population growth rate. In addition, the number of immigrants settling in the colony was positively correlated with colony size in the previous and current year, but was not correlated with fecundity of the previous year. Our results suggest that the variation in immigration affected colony dynamics and that conspecific attraction likely triggered the relevant role of immigration in the growth of a recently formed waterbird colony, supporting the need of including immigration in population analysis. This article is protected by copyright. All rights reserved.

Concepts: Demography, Population, Immigration, Demographic economics, World population, Spoonbill, Eurasian Spoonbill

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Migration is a widespread phenomenon in the animal kingdom. On the basis of the considerable variation that exists between and within species, and even within populations, we may be able to infer the (age- and sex-specific) ecological trade-offs and constraints moulding migration systems from assessments of fitness associated with migration and wintering in different areas. During three consecutive breeding seasons, we compared the reproductive performance (timing of breeding, breeding success, chick body condition and post-fledging survival) of Eurasian spoonbills Platalea leucorodia that breed at a single breeding site in The Netherlands, but migrate different distances (ca. 4,500 km versus 2,000 km, either or not crossing the Sahara) to and from wintering areas in southern Europe and West Africa. Using mark-recapture analysis, we further investigated whether survival until adulthood (recruitment probability) of chicks hatched between 2006 and 2010 was related to their hatch date and body condition. Long-distance migrants bred later, particularly the males, and raised chicks of poorer body condition than short-distance migrants. Hatch dates strongly advanced with increasing age in short-distance migrants, but hardly advanced in long-distance migrants, causing the difference in timing of breeding between long- and short-distance migrants to be more pronounced among older birds. Breeding success and chick body condition decreased over the season, and chicks that fledged late in the season or in poor condition were less likely to survive until adulthood. As a result, long-distance migrants - particularly the males and older birds - likely recruit fewer offspring into the breeding population than short-distance migrants. This inference is important for predicting the population-level consequences of changes in winter habitat suitability throughout the wintering range. Assuming that the long-distance migrants - being the birds that occupy the traditional wintering areas - are not the poorer quality birds, and that the observed age-dependent patterns in timing of breeding are driven by within-individual effects and not by selective disappearance, our results suggest that the strategy of long-distance migration, involving the crossing of the Sahara to winter in West Africa, incurred a cost by reducing reproductive output, albeit a cost paid only later in life. This article is protected by copyright. All rights reserved.

Concepts: Africa, Bird, Season, Breed, Copyright, Winter, Bird migration, Spoonbill

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The parasitic quill mites of the family Syringophilidae (Acariformes: Prostigmata) are recorded on ibises and spoonbills (Pelecaniformes: Threskiornithidae) for the first time. Four new species of the genus Stibarokris Kethley, 1970 are described: 1) S. theristicus Skoracki, Zmudzinski & Unsoeld sp. nov. ex Theristicus caudatus (Boddaert, 1783) from Brazil, 2) S. geronticus Skoracki, Zmudzinski & Unsoeld sp. nov. ex Geronticus calvus (Boddaert, 1783) from South Africa, 3) S. brevisetosus Skoracki & Zmudzinski sp. nov. ex Plegadis falcinellus (L., 1766) from Turkey, and 4) S. plataleus Skoracki & Zmudzinski sp. nov. ex Platalea leucorodia L., 1758 from Austria. Additionally, a key to all described species in the genus is presented, and hypothesis of the Gondwanan origin of syringophilids associated with ibises and spoonbills is briefly discussed.

Concepts: Threskiornithidae, Ibis, Geronticus, Spoonbill, Southern Bald Ibis, Glossy Ibis, Buff-necked Ibis, Eurasian Spoonbill

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The composition, structure and pattern of helminth assemblages associated with the storks (Ciconiidae), ibises and spoonbills (Threskiornithidae) are poorly understood. Here we analyze the prevalence, intensity and diversity of the helminth component communities associated with the white stork Ciconia ciconia and black stork Ciconia nigra, and notice the findings of helminths on Eurasian spoonbill Platalea leucorodia and glossy ibis Plegadis falcinellus obtained in the Czech Republic in years 1962-2013. Comparison with datasets from multiple European countries supports the existence of well-defined local helminth component communities, which are subject to strong geographic variation. The estimated diversity of the helminth component communities reached 11.0±1.6 (C. ciconia) and 12.5±5.4 (C. nigra) species, with the Berger-Parker dominance index reaching only 0.24 and 0.21, respectively. Typically, the dominant species (Chaunocephalus ferox, Tylodelphys excavata and Dictymetra discoidea in C. ciconia, and Cathaemasia hians and Dicheilonema ciconiae in C. nigra) were considered as local, with intermediate host species available onsite. Altogether 10 of the 11 species with known life cycle were capable to complete their life cycle locally, which is in strong contrast with the situation in Czech egrets and herons. In C. ciconia and C. nigra, the highest helminth load was in juveniles, whereas Echinostoma sudanense, absent in the juveniles, was associated with intermediate hosts absent in the study area. Relative prevalence and frequency of helminths associated with male and female C. ciconia was similar to each other. The first systematically collected evidence of the intra-annual changes of the helminth assemblages in storks is provided.

Concepts: Birds of Europe, Birds of Turkey, Stork, Threskiornithidae, Ibis, White Stork, Spoonbill, Ciconia

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Effective population size, levels of genetic diversity, gene flow, and genetic structuring were assessed in 205 colonial Roseate spoonbills from 11 breeding colonies from north, central west, and south Brazil. Colonies and regions exhibited similar moderate levels of diversity at five microsatellite loci (mean expected heterozygosity range 0.50-0.62; allelic richness range 3.17-3.21). The central west region had the highest Ne (59). F ST values revealed low but significant genetic structuring among colonies within the north and within the south regions. Significant global genetic structuring was found between the northern and central western populations as well as between the northern and southern populations. An individual-based Bayesian clustering method inferred three population clusters. Assignment tests correctly allocated up to 64% of individuals to their source regions. Collectively, results revealed complex demographic dynamics, with ongoing gene flow on a local scale, but genetic differentiation on a broader scale. Populations in the three regions may all be conserved, but special concern should be given to central western ones, which can significantly contribute to the species' gene pool in Brazil.

Concepts: Evolution, Population ecology, Population genetics, Brazil, Threskiornithidae, Spoonbill, Roseate Spoonbill, Platalea

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Parastrigea plataleae n. sp. (Digenea: Strigeidae) is described from the intestine of the roseate spoonbill Platalea ajaja (Threskiornithidae) from four localities on the Pacific coast of Mexico. The new species is mainly distinguished from the other 18 described species of Parastrigea based on the ratio of its hindbody length to forebody length. A principal component analysis (PCA) of 16 morphometric traits for 15 specimens of P. plataleae n. sp., five of Parastrigea cincta and 11 of Parastrigea diovadena previously recorded in Mexico, clearly shows three clusters, which correspond to the three species. DNA sequences of the internal transcribed spacers (ITSs) of ribosomal DNA and the mitochondrial gene cytochrome c oxidase subunit I (cox 1) were used to corroborate this morphological distinction. The genetic divergence estimated among P. plataleae n. sp., P. cincta and P. diovadena ranged from 0.5 to 1.48% for ITSs and from 9.31 to 11.47% for cox 1. Maximum parsimony (MP) and maximum likelihood (ML) analyses were performed on the combined datasets (ITSs+cox 1) and on each dataset alone. All of the phylogenetic analyses indicated that the specimens from the roseate spoonbill represent a clade with strong bootstrap support. The morphological evidence and the genetic divergence in combination with the reciprocal monophyly in all of the phylogenetic trees support the hypothesis that the digeneans found in the intestines of roseate spoonbills represent a new species.

Concepts: DNA, Evolution, Biology, Mitochondrion, Phylogenetics, Threskiornithidae, Spoonbill, Roseate Spoonbill

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Abstract When populations grow or decline, habitat selection may change due to local density-dependent processes, such as site dependence and interference. In seasonally migrating animals, nonbreeding distributions may be determined through these mechanisms of density dependence, which we examine here at a hemispheric scale for a long-distance migrating bird. Using summer and winter resightings of 2,095 Eurasian spoonbills Platalea leucorodia leucorodia that were ringed in the Netherlands during 16 years of fast population growth, we show that neither site dependence nor interference fully explains their patterns of survival and winter distribution. Within their three main wintering areas, annual survival decreased with an increase in population size. While survival was consistently higher in the two European wintering areas (France, Iberia), most spoonbills migrated onward to winter in west Africa. The number of birds wintering in Europe increased, but not enough to maximize annual survival. We conclude that a constraint of tradition (their “migration tendency”) inhibits birds from changing their migratory habits. We pose that this phenomenon may similarly constrain other migratory populations from rapidly responding to large-scale climate- and/or human-driven habitat changes at their wintering grounds.

Concepts: Population ecology, Bird, Immigration, Human migration, Change, World population, Bird migration, Spoonbill