Dieter Thomas Tietze

Evolution of leaf warbler songs (Aves: Phylloscopidae)

Songs in passerine birds are important for territory defense and mating. Speciation rates in oscine passerines are so high, due to cultural evolution, that this bird lineage makes up half of the extant bird species. Leaf warblers are a speciose Old-World passerine family of limited morphological differentiation, so that songs are even more important for species delimitation. We took 16 sonographic traits from song recordings of 80 leaf warbler taxa and correlated them with 15 potentially explanatory variables, pairwise, and in linear models. Based on a well-resolved molecular phylogeny of the same taxa, all pairwise correlations were corrected for relatedness with phylogenetically independent contrasts and phylogenetic generalized linear models were used. We found a phylogenetic signal for most song traits, but a strong one only for the duration of the longest and of the shortest element, which are presumably inherited instead of learned. Body size of a leaf warbler species is a constraint on song frequencies independent of phylogeny. At least in this study, habitat density had only marginal impact on song features, which even disappeared through phylogenetic correction. Maybe most leaf warblers avoid the deterioration through sound propagation in dense vegetation by singing from exposed perches. Latitudinal (and longitudinal) extension of the breeding ranges was correlated with most song features, especially verse duration (longer polewards and westwards) and complexity (lower polewards). Climate niche or expansion history might explain these correlations. The number of different element types per verse decreases with elevation, possibly due to fewer resources and congeneric species at higher elevations.

Molecular phylogeny of Old World swifts (Aves: Apodiformes, Apodidae, Apus and Tachymarptis) based on mitochondrial and nuclear markers.

We provide a molecular phylogeny for Old World swifts of genera Apus and Tachymarptis (tribe Apodini) based on a taxon-complete sampling at the species level. Phylogenetic reconstructions were based on two mitochondrial (cytochrome b, 12S rRNA) and three nuclear markers (introns of fibrinogen and glyceraldehyde 3-phosphate dehydrogenase plus anonymous marker 12884) while the myoglobin intron 2 did not show any intergeneric variation or phylogenetic signal among the target taxa at all. In contrast to previous hypotheses, the two genera Apus and Tachymarptis were shown as reciprocally monophyletic in all reconstructions. Apus was consistently divided into three major clades: (1) East Asian clade of A. pacificus and A. acuticauda, (2) African-Asian clade of A. caffer, A. batesi, A. horus, A. affinis and A. nipalensis, (3) African-Palearctic clade of eight currently accepted species among which sequences of A. apus and A. pallidus clustered in a terminal crown clade. Phylogenetic signal of all four nuclear markers was extremely shallow within and among species of tribe Apodini and even among genera, such that intra- and intergeneric relationships of Apus, Tachymarptis and Cypsiurus were poorly resolved by nuclear data alone. Four species, A. pacificus, A. barbatus, A. affinis and A. caffer were consistently found to be paraphyletic with respect to their closest relatives and possible taxonomic consequences are discussed without giving particular recommendations due to limitations of sampling. Incomplete mitochondrial lineage sorting with cytochrome-b haplotypes shared among species and across large geographic distances was observed in two species pairs: A. affinis/A. nipalensis and A. apus/A. pallidus. Mitochondrial introgression caused by extant or past gene flow was ruled out as an explanation for the low interspecific differentiation in these two cases because all nuclear markers appeared to be highly unsorted among Apus species, too. Apparently, the two extant species pairs originated from very recent dispersal and/or speciation events. The currently accepted superspecies classification within Apus was not supported by our results.

Epidemic Spread of Usutu Virus in Southwest Germany in 2011 to 2013 and Monitoring of Wild Birds for Usutu and West Nile Viruses

Mosquito-borne viruses are becoming an increasing threat for Europe. One of these viruses is Usutu virus (USUV), a single-stranded RNA virus belonging to the Japanese encephalitis virus group within the family Flaviviridae. Since the occurrence of USUV among wild birds in June, 2011, infected Blackbirds (Turdus merula) have frequently been found dead in southwest Germany, cumulating in a massive die-off. Moreover, other bird species (Strigiformes) in this region have been affected. In a first study, 209 of over 600 dead birds (wild birds and birds kept in aviaries) collected from 2011 to 2013 carried USUV, more than 88% of them Blackbirds. USUV had already been detected in 2010, one year before the epizooty, in a mosquito-based surveillance program in Germany. The main epidemic area of the USUV outbreak in wild birds in southwest Germany has been similar for the last three years. In a second study during 2011 to 2013, 902 live migratory and resident birds (representing 87 bird species belonging to 14 bird orders) from four different sampling sites were bled and tested serologically and by qPCR for West Nile virus (WNV) and USUV infections. No USUV or WNV genomes were detected. Some migratory birds (mainly long-distance migrants and some partial migrants) carried neutralizing antibodies against WNV as discriminated by USUV and WNV cross-neutralization tests. Only few resident birds showed relevant USUV-specific neutralizing antibodies. The occurrence of USUV in the Upper Rhine valley area of southwest Germany is a proof of principle for the incursion and spread of other arthropod-borne (arbo)-viruses along these routes. Therefore, monitoring studies in birds and mosquitoes for the presence of arboviruses in these areas are indispensable.

Evolutionary history of passerine birds (Aves: Passeriformes) from the Qinghai–Tibetan plateau: from a pre-Quarternary perspective to an integrative biodiversity assessment

As one of the most prominent topographical features on Earth, the Qinghai–Tibetan plateau (QTP) underwent a long and complex history of the QTP uplift from the collision of the Indian and the Eurasian plates to the present. At its southern and southeastern margins, it is flanked by the most significant hotspots of organismic diversity of the northern hemisphere (including birds), the Sino-Himalayan mountain forests. In contrast, the central plateau region itself harbours species-poor communities but also a good number of endemics that presumably evolved from rather ancient (pre-Pleistocene) phylogenetic lineage splits. We discuss the evolutionary history of QTP passerines from a twofold perspective including examples from our own research. First, we provide an overview of those alpine QTP endemics that represent late Miocene and Pliocene lineage splits, i.e. early colonisations to the central alpine QTP region. As an example, true rosefinches (genus Carpodacus) presumably evolved from a forested eastern QTP centre of origin and colonised the (semi-)open plateau habitats several times independently. Second, we discuss younger speciation events corresponding to phylogeographic east–west divides along the southern QTP margin. A multidisciplinary approach combining genetic, bioacoustic and morphological markers shed new light on the phylogenetic relationships of Pnoepyga wren babblers and on the intraspecific subdivision of the Buff-barred Warbler (Phylloscopus pulcher).

A multilocus molecular phylogeny for the avian genus Liocichla (Passeriformes: Leiothrichidae: Liocichla)

BackgroundHistorically the babblers have been assigned to the family Timaliidae but several recent studies have attempted to rest the taxonomy of this diverse passerine assemblage on a more firm evolutionary footing. The result has been a major rearrangement of the group. A well-supported and comprehensive phylogeny for this widespread avian group is an important part of testing evolutionary and biogeographic hypotheses, especially in Asia where the babblers are a key component of many forest ecosystems. However, the genus Liocichla is poorly represented in these prior studies of babbler systematics.MethodsWe used a multilocus molecular genetic approach to generate a phylogenetic hypothesis for all five currently recognized species in the avian genus Liocichla. Multilocus DNA sequence data was used to construct individual gene trees using maximum likelihood and species trees were estimated from gene trees using Bayesian analyses. Divergence dates were obtained using a molecular clock approach.ResultsMolecular data estimate a probable window of time for the origin for the Liocichla from the mid to late Miocene, between 5.55 and 12.87xa0Ma. Despite plumage similarities between the insular Taiwan endemic, L. steerii, and the continental L. bugunorum and L. omeiensis, molecular data suggest that L. steerii is the sister taxon to all continental Liocichla. The continental Liocichla are comprised of two lineages; a lineage containing L. omeiensis and L. bugunorum and a lineage comprised of L. phoenicea and L. ripponi. The comparatively early divergence of L. steerii within the Liocichla may be illusory due to extinct and therefore unsampled lineages. L. ripponi and L. phoenicea are parapatric with a Pleistocene split (0.07–1.88xa0Ma) occurring between an Eastern Himalayan L. phoenicea and a Northern Indochina distributed L. ripponi. L. bugunorum and L. omeiensis underwent a similar split between the Eastern Himalaya (L. bugunorum) and Central China (L. omeiensis) divided by the Hengduan Mountains.ConclusionsThis study supports an origin of the Liocichla occurring sometime prior to the Miocene–Pliocene boundary, a period of significant climatic upheaval in Asia. The biogeographical patterns within the Liocichla mirror those of other birds in the region and allude to common geological and climatic drivers of avian diversification in Asia.

Scavenging of small bird carrion in southwestern Germany by beetles, birds and mammals

When considering the impact of wind turbines on the mortality of birds and bats, it is important to know the length of time that a carcass will be detectable. Thousands of small animals (such as many passerine birds with high mortality rates) die every day, but dead animals are rarely found by casual observers in the field. What is the fate of small carcasses in European ecosystems? During this project, we placed 120 defrosted day-old chicks (Gallus gallus f. domestica) as a model for a small carcass in a variety of habitats in southwestern Germany between the end of May and the beginning of December 2014. Using automatic trail cameras, we recorded the scavengers which visited the carrion or were feeding on it. Overall, two-thirds of the carcasses were removed under these conditions within a 5-day period. During the summer months, 20xa0% of the chicks were buried by burying beetles (Nicrophorus sp.), and 40xa0% were removed by nine mammal and three bird species. The most important vertebrate scavengers were the Red Fox (Vulpes vulpes), the Common Buzzard (Buteo buteo), the European Magpie (Pica pica) and the Domestic Cat (Felis catus). Among the scavenged chicks, 38.8xa0% vanished during the first 24xa0h of exposure. The median persistence time was 2.79 days. Persistence times were not dependent on habitat type, but carrion persisted longer on average in autumn than in summer. Knowledge of the factors influencing carcass persistence is important for estimating mortality in songbirds or bats in the context of wind turbines.ZusammenfassungWer entsorgt tote Kleinvögel? Die Rolle von Totengräbern, Vögeln und Säugetieren in Südwestdeutschland Wenn man die Gefährdung von Vögeln und Fledermäusen durch Windkraftanlagen ermitteln möchte, muss man wissen, wie lange tote Tiere auffindbar bleiben. Im Projekt wurden von Ende Mai bis Anfang Dezember 2014 insgesamt 120 aufgetaute Eintagsküken in verschiedenen Lebensräumen in Südwestdeutschland mit Hilfe von automatischen Wildkameras überwacht. Insgesamt wurden zwei Drittel der ausgelegten Kadaver innerhalb von fünf Tagen entfernt. 20xa0% wurden von Totengräbern (Nicrophorus sp.) vergraben, wobei der Anteil im Jahresverlauf abnahm. 40xa0% der Küken wurden von insgesamt neun Säugetier- und drei Vogelarten gefressen. Unter den Wirbeltieren waren Rotfuchs (Vulpes vulpes), Mäusebussard (Buteo buteo), Elster (Pica pica) und Hauskatze (Felis catus) die wichtigsten Aasfresser. Über 38xa0% der ausgelegten toten Küken verschwand innerhalb der ersten 24 h. Der Median der Persistenzzeit betrug 2,79 d. Es konnte kein Zusammenhang zwischen Habitattypen und Persistenzzeiten festgestellt werden; die Küken blieben jedoch im Herbst im Durchschnitt länger liegen als im Sommer. Die Umgebungstemperatur kann in diesem Zusammenhang als wichtiger Faktor angesehen werden. Diese Erkenntnisse sind ein erster Schritt, um die Gefährdung von Singvögeln oder Fledermäusen an Windkraftanlagen besser einschätzen zu können.

Seasonal patterns of urban bird diversity in a Mediterranean coastal city: the positive role of open green spaces

Urbanization causes rapid changes in the landscape and land use, exerting a significant pressure on bird communities. The effect of urbanization on bird diversity has been widely investigated in many cities worldwide; however, our knowledge on urban bird communities from the eastern Mediterranean region is very scarce. In this context, we aimed to investigate the effect of the different land-cover types on bird species richness and abundance in a densely built coastal Mediterranean city (Patras, Greece) during the breeding and wintering seasons. We sampled the bird community in 90 randomly selected sites along an urbanization gradient. Open green spaces proved to be the most significant factor favouring bird diversity in both seasons. In winter, woody vegetation and impervious surfaces had a positive effect on species richness as well. The local bird community consisted of a large number of species associated with open and semi-open unmanaged green areas, 12 of which are Species of European Conservation Concern (SPECs) showing a declining trend in Europe. On the other hand, in winter the number of forest-dwellers increased significantly. Species richness was significantly higher in winter indicating that the urban environment provides important wintering grounds. Thus, management actions in cities with similar characteristics in the Mediterranean region should focus on the maintenance of open green spaces and woody vegetation patches to enhance bird diversity.

Does urbanization affect wing pointedness in the Blackbird Turdus merula

AbstractColonization of urban habitats requires physiological, behavioral and morphological changes in many species. This is well studied in the Common Blackbird (Turdus merula), one of the most common bird species in Europe. Former studies found that urban Blackbirds show decreased migratory behavior. However, it is still a matter of debate whether this is linked to morphological changes. According to Seebohm’s rule, sedentary individuals have less pointed wings in contrast to migratory individuals. Here we assess if wing pointedness—as measured by Kipp’s index—decreases along a rural to urban gradient in Blackbirds. To determine this, Blackbirds were caught in Frankfurt am Main and Heidelberg, as well as in the neighboring uplands of the Taunus and Odenwald, along a virtual continuous urbanization gradient, ranging from nearby forests to city centers. Along this gradient, wing pointedness significantly decreased in male, but not in female, Blackbirds. However, this trend was no longer significant when considering single regions. This indicates that wing pointedness does not change uniformly across the species’ range because of different intensities of urbanization. Sex-specific differences might be due to distinct territorial and dominance behavior. Variations in wing shape of urban and rural Blackbird populations are most likely based on a combination of better climatic conditions and increased food availability, as well as behavior adjusted to urban habitats. This study shows urbanization effects on the wing morphology of Blackbirds that might coincide with reduced migratory behavior.ZusammenfassungBeeinflusst die Urbanisierung die Flügelspitzigkeit bei der AmselTurdus merula?n Die Besiedlung urbaner Lebensräume erfordert bei vielen Arten Veränderungen in Physiologie, Verhalten und Morphologie. Dies ist bei der Amsel (Turdus merula) gut untersucht, einer der häufigsten Vogelarten in Europa. Frühere Studien fanden heraus, dass Stadt-Amseln ein reduziertes Zugverhalten zeigen. Allerdings ist es immer noch umstritten, ob dies mit morphologischen Veränderungen einhergeht. Nach Seebohm’s Regel besitzen nicht-ziehende Individuen weniger spitze Flügel als ziehende Individuen. In dieser Studie untersuchten wir, ob die Flügelspitzigkeit—basierend auf dem Kipp-Index—bei Amseln entlang eines Land-Stadt-Gradienten abnimmt. Um dies festzustellen, wurden Amseln in Frankfurt am Main und Heidelberg sowie in den angrenzenden Mittelgebirgen Taunus und Odenwald gefangen, und zwar entlang eines virtuellen kontinuierlichen Urbanisierungsgradienten, der von nahegelegenen Wäldern bis in die Innenstädte hineinreicht. Entlang dieses Gradienten nahm die Flügelspitzigkeit bei männlichen, aber nicht bei weiblichen Amseln signifikant ab. Dieser Trend ist jedoch nicht mehr signifikant, wenn die Regionen separat betrachtet werden. Das bedeutet, dass sich die Flügelspitzigkeit aufgrund unterschiedlicher Urbanisierungsintensitäten nicht einheitlich über das Artareal hinweg ändert. Geschlechterspezifische Unterschiede gehen möglicherweise auf unterschiedliches Territorial- und Dominanzverhalten zurück. Variationen in der Flügelform von Stadt- und Landpopulationen der Amsel basieren höchstwahrscheinlich auf einer Kombination von besseren klimatischen Bedingungen und höherer Nahrungsverfügbarkeit sowie an städtische Habitate angepasstem Verhalten. Diese Studie zeigt Auswirkungen der Verstädterung auf die Flügelmorphologie von Amseln, die möglicherweise mit reduziertem Zugverhalten in Zusammenhang stehen.

How weather instead of urbanity measures affects song trait variability in three European passerine bird species

Abstract Previous studies detected an influence of urban characteristics on song traits in passerine birds, that is, song adjustments to ambient noise in urban areas. Several studies already described the effect of weather conditions on the behavior of birds, but not the effect on song traits. We investigate, if song trait variability changes along a continuous urbanity gradient in Frankfurt am Main, Germany. We examined, for the first time on a larger scale, the influence of weather on song parameters. We made song recordings of three common passerine species: the blue and great tit (Cyanistes caeruleus (Linnaeus, 1758) and Parus major Linnaeus, 1758) and the European blackbird (Turdus merula Linnaeus, 1758). We measured different song traits and performed statistical analyses and modeling on a variety of variables—among them urbanity and weather parameters. Remarkably, we found only few cases of a significant influence of urbanity parameters on song traits. The influence of weather parameters (air pressure, atmospheric humidity, air and soil temperatures) on song traits was highly significant. Birds in Frankfurt face high noise pollution and might show different adaptations to high noise levels. The song trait variability of the investigated species is affected more by weather conditions than by urban characteristics in Frankfurt. However, the three species react differently to specific weather parameters. Smaller species seem to be more affected by weather than larger species.

New Microsatellite Markers for the Common Tern (Sterna hirundo) Developed with 454 Shot-Gun Pyrosequencing

Long term studies, focusing on populationand socio-biology research, require the unequivocal identification of individuals. DNA studies with Short Tandem Repeats (STR loci) became a widespread tool in population genetics. We used the nextgeneration sequencing (NGS) approach with 454 shot-gun pyrosequencing to identify 13 new polymorphic STR loci for the Common Tern, Sterna hirundo. To enlarge the marker set we added two more loci originally developed for Black-legged Kittiwake (Rissa tridactyla) and Red-billed Gull (Chroicocephalus scopulinus) and arranged these 15 loci into three multiplex PCR panels for high throughput genotyping. Loci characterization demonstrated that our marker set is of high quality. A PIC value of about 0.67 and a power of exclusion value of 0.99 were reached. Deviation from Hardy-Weinberg expectations of some loci and low frequencies for null alleles are interpreted as a result of inbreeding and founder effect in the investigated tern colony. We used a test data set of this well-studied breeding colony of Common Tern at Banter Lake, Wilhelmshaven, Germany, to perform a parentage test. Parent-chick relationships, known from the social pedigree of that colony, were compared with genetically calculated ones. In order to test our markers and the used parentage program COLONY, we conducted six competing data sets with varying completeness of included parental genotypes. By including fully sampled parent pairs of known family assignment, results were correct for nest mates, single parents and parent pairs. Our marker set provides a powerful tool to investigate life-time reproductive success and other issues of population and socio-biology for Common Terns, e.g. in the aforementioned colony monitored for decades.