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Item A wood-concrete nest box to study burrow-nesting petrels(2016) Bedolla-Guzmán, Yuliana; Masello, Juan F.; Aguirre-Muñoz, Alfonso; Quillfeldt, PetraItem Acute stress hyporesponsive period in nestling Thin-billed prions Pachyptila belcheri(2009) Quillfeldt, Petra; Poisbleau, Maud; Chastel, Olivier; Masello, Juan F.When confronted with acute stressors, vertebrates show a highly conserved evolved sequence of physiological, hormonal and behavioural responses, including the activation of the hypothalamic-pituitary-adrenal axis. Many young vertebrates show a stress hyporesponsive period, where they exhibit a reduced glucocorticoid response. Here, we analyzed the stress response of nestling Thin-billed prions Pachyptila belcheri and compared chicks with different previous experience with capture and handling. We found that chicks had a stress response, but baseline and peak levels were below those measured in adults. The stress response of the chicks was rapid and followed by fast recovery, such that the total amount of corticosterone released in response to handling was very much lower in chicks than adults. These results indicate that nestling Thin-billed prions exhibit a stress hyporesponsive period. This was not due to habituation, as CORT measurements at baseline and elevated levels were similar in chicks handled daily and naïve chicks. The comparison with other published studies showed that the stress response of chicks usually peaks earlier and lower than in adults, and researchers should take care to measure stress-induced levels at an appropriate sampling time.Item Additive Traits Lead to Feeding Advantage and Reproductive Isolation, Promoting Homoploid Hybrid Speciation(2019-04-26) Masello, Juan F; Quillfeldt, Petra; Sandoval-Castellanos, Edson; Alderman, Rachael; Calderón, Luciano; Cherel, Yves; Cole, Theresa L; Cuthbert, Richard J; Marin, Manuel; Massaro, Melanie; Navarro, Joan; Phillips, Richard A; Ryan, Peter G; Shepherd, Lara D; Suazo, Cristián G; Weimerskirch, Henri; Moodley, YoshanSpeciation through homoploid hybridization (HHS) is considered extremely rare in animals. This is mainly because the establishment of reproductive isolation as a product of hybridization is uncommon. Additionally, many traits are underpinned by polygeny and/or incomplete dominance, where the hybrid phenotype is an additive blend of parental characteristics. Phenotypically intermediate hybrids are usually at a fitness disadvantage compared with parental species and tend to vanish through backcrossing with parental population(s). It is therefore unknown whether the additive nature of hybrid traits in itself could lead successfully to HHS. Using a multi-marker genetic data set and a meta-analysis of diet and morphology, we investigated a potential case of HHS in the prions (Pachyptila spp.), seabirds distinguished by their bills, prey choice, and timing of breeding. Using approximate Bayesian computation, we show that the medium-billed Salvin's prion (Pachyptila salvini) could be a hybrid between the narrow-billed Antarctic prion (Pachyptila desolata) and broad-billed prion (Pachyptila vittata). Remarkably, P. salvini's intermediate bill width has given it a feeding advantage with respect to the other Pachyptila species, allowing it to consume a broader range of prey, potentially increasing its fitness. Available metadata showed that P. salvini is also intermediate in breeding phenology and, with no overlap in breeding times, it is effectively reproductively isolated from either parental species through allochrony. These results provide evidence for a case of HHS in nature, and show for the first time that additivity of divergent parental traits alone can lead directly to increased hybrid fitness and reproductive isolation.Item Amorphous and highly nonstoichiometric titania (TiOx) thin films close to metal-like conductivity(2014) Leichtweiss, Thomas; Henning, Ralph A.; Koettgen, Julius; Schmidt, Rüdiger M.; Holländer, Bernd; Martin, Manfred; Wuttig, Matthias; Janek, JürgenOxygen-deficient titanium oxide films (TiOx) have been prepared by pulsed laser deposition at room temperature. Samples in their as-deposited state have an average composition of TiO1.6, are optically absorbing and show electronic conductivities in the range of 10 S cm-1. The films are metastable and consist of grains of cubic titanium monoxide (gamma-TiO) embedded in an amorphous TiO1.77 matrix. Upon annealing in an argon atmosphere the electrical conductivity of the films increases and comes close to metal-like conductivity (1000 S cm-1) at about 450 [degree]C whereas the local structure is changed: nanocrystalline grains of metallic Ti are formed in the amorphous matrix due to an internal solid state disproportionation. The highly conductive state can be frozen by quenching. During heat treatment in an argon atmosphere a stoichiometric rutile TiO2 surface layer forms due to oxidation by residual oxygen. The combination of a highly conductive TiOx film with such an approximately 20 nm thick rutile cover layer leads to a surprisingly high efficiency for the water-splitting reaction without the application of an external potential.Item Are acoustical parameters of begging call elements of thin-billed prions related to chick condition?(2010) Quillfeldt, Petra; Poisbleau, Maud; Mundry, Roger; Masello, Juan F.Chicks of burrowing petrels use begging calls to advertise their hunger levels when parents arrived at the nest. In a previous study, adult thin-billed prions Pachyptila belcheri responded to higher begging call rates of their single chick by regurgitating larger meals. We tested whether acoustic parameters of begging call elements may also be involved in signalling. To describe variation in begging, we determined begging session parameters, namely the duration, number of calls and the mean and maximum rate of calling. We then digitised calls and carried out a semi-automatic extraction of six acoustic parameters of call elements, including mean and maximum acoustic frequency, the length of call elements and the location of the maximum frequency and amplitude within calls. Chicks showed strong individual differences in all parameters. While the session parameters were correlated with body condition and with the meal size the chick received, none of the acoustic parameters were related to body condition and provisioning. A cross-fostering experiment showed the same pattern, as only session parameters changed related to an experimentally altered body condition, while acoustical cues appear to play no role in signalling hunger levels. We suggest that this may be explained by the absence of sibling competition in these birds. As parents do not need to decide which chick to feed, immediate information on condition at the time of adult arrival may not be required.Item Aspects of the breeding biology of the southern rockhopper penguin Eudyptes c. chrysocome and new consideration on the intrinsic capacity of the A-egg(2008) Poisbleau, Maud; Demongin, Laurent; Strange, Ian J.; Otley, Helen; Quillfeldt, PetraThe rockhopper penguins Eudyptes chrysocome have recently been split into the northern E. moseleyi and the southern E. chrysocome rockhopper penguin. It is therefore crucial to have a comprehensive understanding of the biology of each species in order to develop appropriate conservation measures. We investigated the breeding biology of the southern rockhopper on New Island, in the western part of the Falklands Islands, by following the breeding attempt of 160 pairs during the 2006/2007 season and examining the effect of lay time and colony habitat on breeding success. Specifically, we compared survival and growth parameters between A- and B-eggs and chicks from non-manipulated and artificially manipulated nests to investigate why southern rockhopper penguins in the Falkland Islands are more able to fledge an A-egg (first laid) than conspecifics elsewhere. Breeding was highly synchronous, with no significant difference in the breeding success between early and late breeders or between pairs breeding in different habitats. We demonstrate for the first time that the A-egg produced by the southern rockhopper penguin has, when alone, the same theoretical intrinsic potential to lead to a fledged chick as the B-egg. In contrast, the hatching success and survival of the B-chick was similar when alone or in a two-egg clutch.Item Bimodal mesoporous titanium dioxide anatase films templated by a block polymer and an ionic liquid: influence of the porosity on the permeability(2013) Sallard, Sébastien; Schröder, Michael; Boissière, Cédric; Dunkel, Christian; Etienne, Mathieu; Walcarius, Alain; Oekermann, Torsten; Wark, Michael; Smarsly, Bernd M.In the present paper, we report the synthesis of bimodal mesoporous anatase TiO2 films by the EISA (Evaporation-Induced Self-Assembly) method using sol-gel chemistry combining two porogen agents, a low molecular weight ionic template and a neutral block copolymer. The surfactant template (C(16)mimCl) generates non-oriented worm-like pores (8 to 10 nm) which connect the regularly packed ellipsoidal mesopores (15 to 20 nm diameter) formed by an amphiphilic block copolymer of the type poly(isobutylene)-b-poly(ethylene oxide) (PIB-PEO). The surfactant template can also significantly influence the size and packing of the ellipsoidal mesopores. The mesostructural organization and mesoporosity of the films are studied by Environmental Ellipsometry-Porosimetry (EEP), Grazing-Incidence Small-Angle X-ray Scattering (GISAXS) and electron microscopy techniques. Electrochemical characterization is performed to study the permeability of the films to liquid solutions, using two types of probe moieties (K3FeIII(CN)(6) and Ru(bpy)(3)(2+)) by the wall-jet technique. An optimum ratio of C(16)mimCl/PIB-PEO provides anatase films with a continuous bimodal mesopore structure, possessing a permeability up to two times higher than that of the mesoporous films templated by PIB-PEO only (with partially isolated mesopores). When C(16)mimCl is used in large quantities, up to 20% weight vs. PIB-PEO, large overall porous volume and surface area are obtained, but the mesostructure is increasingly disrupted, leading to a severe loss of permeability of the bimodal films. A dye-sensitized solar cell set-up is used with anatase films as the photoelectrode. The photosensitizer loading and the total energy conversion efficiency of the solar cells using the mesoporous films templated by an optimal ratio of the two porogen agents C(16)mimCl and PIB-PEO can be substantially increased in comparison with the solar cells using mesoporous films templated by PIB-PEO only.Item Birds from the endangered Monte, the steppes and coastal biomes of the province of Río Negro, northern Patagonia, Argentina(2011) Llanos, Fabián A.; Failla, Mauricio; García, Gustavo J.; Giovine, Pablo M.; Carbajal, Mirta; González, Patricia M.; Paz Barreto, Daniel; Quillfeldt, Petra; Masello, Juan F.The main ecosystem in northern Patagonia, Argentina, is the Monte, a semi-desert scrubland home to a high biodiversity. Monte is the most endangered ecosystem of southern South America, with an annual rate of clearance of the native vegetation estimated at 3.7%. Here we report the results of bird surveys carried out in the province of Río Negro, northern Patagonia. We surveyed four localities mostly dominated by the Monte ecosystem, between 1986 and 2010. Three localities are Important Bird Areas (IBAs): El Cóndor, San Antonio Oeste and Meseta de Somuncurá. The fourth locality is the Paso Córdoba nature reserve. We recorded a total of 263 bird species. The highest species richness was observed at San Antonio Oeste, followed by El Cóndor. Information regarding the period of occurrence and habitats are provided for all species and localities. Additionally, we indicated the cases in which breeding behavior was observed. This information is urgently needed for the evaluation of the consequences of habitat destruction and deterioration as well as for the success of intended remediation measures.Item Blood and Intestinal Parasites in Wild Psittaciformes: A Case Study of Burrowing Parrots (Cyanoliseus Patagonus)(2006) Masello, Juan F.; Choconi, R. Gustavo; Sehgal, Ravinder N.M.; Tell, Lisa; Quillfeldt, PetraQuantifying parasites is essential for understanding the ecological and evolutionary implications of parasites on their hosts. It is also crucial for many conservation attempts carried out in endangered groups of birds, like the Psittaciformes. The aim of the present study was to test for the presence of blood and intestinal parasites of Burrowing Parrots (Cyanoliseus patagonus) (Psittaciformes) breeding in a large colony at the Atlantic coast of Patagonia, Argentina. Although Burrowing Parrots in this colony have several blood-sucking ectoparasites, no blood parasite was detected in blood smears or with the use of a PCR detection method. Likewise, faecal samples of Burrowing Parrots contained no eggs or oocysts of intestinal parasites. We also review the literature on blood and intestinal parasites in wild Psittaciformes, showing that blood parasites were absent in all cases, and 20 out of 28 studies were negative for intestinal parasites. The observed apparent absence of blood parasites in Burrowing Parrots and other Neotropical Psittaciformes is in line with the theory that avian hemosporidians could have been evolved in the tropics of the Old World, where they are widely distributed and prevalent, and they probably penetrated to Central and South America through the Nearctic region of the Holarctic recently. The observed apparent absence of blood parasites could also be explained by innate immunity in Psittaciformes, as has recently been suggested for other long-lived birds.Item Blood parasites in noddies and boobies from Brazilian offshore islands : differences between species and influence of nesting habitat(2014) Quillfeldt, Petra; Martinez, Javier; Bugoni, Leandro; Mancini, Patricia L.; Merino, SantiagoSeabirds are often free from blood parasites, and a recent review suggested that phylogenetic, ecological and life-history parameters can determine the prevalence of blood parasites in seabirds. However, there is a lack of data available frommany seabird groups, and a larger database is needed to understand prevalence patterns of blood parasites. We used a molecular screening approach to detect parasites of the genera Plasmodium, Haemoproteus, Leucocytozoon and Babesia in five species of two genera of seabirds that breed on Atlantic Ocean islands off Brazil. The observed patterns differed between the two bird genera. Like other Laridae, brown noddy, Anous stolidus adults were infected with Haemoproteus with low prevalence. Masked boobies, Sula dactylatra and brown boobies, Sula leucogaster were infected with Babesia. Of the latter, mainly juveniles were infected. In all species, intensity of infection (i.e. number of infected erythrocytes) was so low that parasites remained undetected in blood smears. This may explain the absence of major effects on the body condition of birds, although infected juvenile masked boobies were lighter than juveniles that were not infected with Babesia. Two tree-nesting species; black noddy, Anous minutus and red-footed booby, Sula sula did not have blood parasites, suggesting that treenesting may reduce the exposure to arthropod vectors compared with ground nesting in these species.Item Book review on Heinrich Reichert´s "Neurobiologie"(1991) Schmidt, RupertItem Brachsysteme und Zelgengebundener Anbau in Zentral- und Ostnepal(1973) Haffner, WillibaldDie sehr variablen geographischen und klimatischen Bedingungen in Nepal resultieren in einer Bandbreite agrarischer Anbaumethoden. Während in tieferen Lagen der Nassreisanbau dominiert, gibt es in größeren Höhen eine vielfältige, den Jahreszeiten angepasste Fruchtfolge. Brachen werden verbreitet genutzt.Item Breeding biology, chick growth, and diet of the Least Storm-Petrel Oceanodroma microsoma on Islas San Benito, Mexico(2017) Bedolla-Guzmán, Yuliana; Masello, Juan F.; Aguirre-Muñoz, Alfonso; Lavaniegos, Bertha E.; Quillfeldt, PetraThe Least Storm-Petrel Oceanodroma microsoma is endemic to islands on both coasts of Baja California, in Mexico. It is the smallest seabird species and one of the least studied of the order Procellariiformes. We present a detailed account of its breeding success, chick growth, and diet at Islas San Benito, Baja California, during three consecutive breeding seasons (2013 to 2015) and of sex differences in adult morphology, a study conducted in 2012. Eggs hatched between late July and mid-September, and the fledging period started in mid-October. The timing of breeding varied from year to year: the hatching period began earlier in 2013 than in 2015 and was longer in 2014, while the fledging period started later in 2014 than in 2013. Hatching success (around 80%) and fledging success (about 90%) were consistently high in all three years. Nevertheless, nestlings fledged with longer wings, tails, and bills in 2015. Four species of euphausiids, two species of larval fish, and one species of squid were identified in food samples. Differences in the timing of breeding and chick growth during the period of this study may reflect a variation in food supply associated with anomalous climate conditions recorded in 2014 and 2015.Item Burrowing Parrots an agricultural pest?(2005) Pérez, M. Rita; Failla, Mauricio; Seijas, Verónica; Quillfeldt, Petra; Masello, Juan F.Item Can faecal glucocorticoid metabolites be used to monitor body condition in wild Upland geese Chloephaga picta leucoptera?(2011-07-01) Gladbach, Anja; Gladbach, David Joachim; Koch, Martina; Kuchar, Alexandra; Möstl, Erich; Quillfeldt, PetraThe measurement of faecal glucocorticoid metabolites is used as a non-invasive technique to study stress in animal populations. They have been used most widely in mammals, and mammalian studies have also treated issues such as sample stability and storage methods. In birds, faecal corticosterone metabolite (CM) assays have been validated for a small number of species, and adequate storage under field conditions has not been addressed explicitly in previous studies. Furthermore, while it is well-established that baseline plasma corticosterone levels in birds rise with declining body condition, no study so far investigated if this relationship is also reflected in faecal samples. We here present data of a field study in wild Upland geese Chloephaga picta leucoptera on the Falkland Islands, testing different storage methods and investigating the relationship of faecal CM concentrations to body condition and reproductive parameters. We found that faecal CM measures are significantly repeatable within individuals, higher in individuals with lower body condition in both male and female wild Upland geese and higher in later breeding females with smaller broods. These results suggest that measuring faecal CM values may be a valuable non-invasive tool to monitor the relative condition or health of individuals and populations, especially in areas where there still is intense hunting practice.Item Changes in subcellular distribution of ependymins in goldfish brain induced by learning(1987) Schmidt, Rupert