Settling Decisions and Heterospecific Social Information Use in Shrikes

Animals often settle near competitors, a behavior known as social attraction, which belies standard habitat selection theory. Two hypotheses account for these observations: individuals obtain Allee benefits mediated by the physical presence of a competitor, or they use successfully settled individual as a source of information indicating the location of high quality habitat. We evaluated these hypotheses experimentally in two species of shrikes. These passerine birds with a raptor-like mode of life impale prey to create larders that serve as an indicator of male/habitat quality. Thus, two forms of indirect information are available in our system: a successfully settled shrike and its larder. Typically these two cues are associated with each other, however, our experimental treatment created an unnatural situation by disassociating them. We manipulated the presence of larders of great grey shrikes and examined the settling decisions of red-backed shrikes within and outside the great grey shrike territories. Male red-backed shrikes did not settle sooner on plots with great grey shrikes compared to plots that only contained artificial larders indicating that red-backed shrikes do not use the physical presence of a great grey shrike when making settling decisions which is inconsistent with the Allee effect hypothesis. In contrast, for all plots without great grey shrikes, red-backed shrikes settled, paired and laid clutches sooner on plots with larders compared to plots without larders. We conclude that red-backed shrikes use larders of great grey shrikes as a cue to rapidly assess habitat quality

Expression analysis of somatic embryogenesis-related SERK, LEC1, VP1 and NiR ortologues in rye (Secale cereale L.)

The genetic basis of the regeneration process in cultured immature embryos of rye (Secale cereale L.) was analyzed. The experiments were designed to reveal differences between the in vitro culture responses of two inbred lines: L318 (a high regeneration ability) and L9 (a low potential for regeneration). The rye ortologues of plant genes previously recognized as crucial for somatic embryogenesis and morphogenesis in vitro were identified. Using oligonucleotide primers designed to conserved regions of the genes Somatic Embryogenesis Receptor-like Kinase (SERK), Leafy Cotyledon 1 (LEC1), Viviparous 1 (VP1) and NiR (encoding ferredoxin-nitrite reductase), it was possible to amplify specific homologous sequences from rye RNA by RT-PCR. The transcript levels of these genes were then measured during the in vitro culture of zygotic embryos, and the sites of expression localized. The expression profiles of these genes indicate that their function is likely to be correlated with the in vitro response of rye. In line L9, increased expression of the rye SERK ortologue was observed at most stages during the culture of immature embryos. The suppression of ScSERK expression appears to start after the induction of somatic embryogenesis and lasts up to plant regeneration. The rye ortologues of the LEC1 and VP1 genes may function in a complimentary manner and have a negative effect on the production of the embryogenic callus. The expression of the rye NiR ortologue during in vitro culture reveals its importance in the process of plant regeneration

Maladaptive Habitat Selection of a Migratory Passerine Bird in a Human-Modified Landscape

In human-altered environments, organisms may preferentially settle in poor-quality habitats where fitness returns are lower relative to available higher-quality habitats. Such ecological trapping is due to a mismatch between the cues used during habitat selection and the habitat quality. Maladaptive settlement decisions may occur when organisms are time-constrained and have to rapidly evaluate habitat quality based on incomplete knowledge of the resources and conditions that will be available later in the season. During a three-year study, we examined settlement decision-making in the long-distance migratory, open-habitat bird, the Red-backed shrike (Lanius collurio), as a response to recent land-use changes. In Northwest Europe, the shrikes typically breed in open areas under a management regime of extensive farming. In recent decades, Spruce forests have been increasingly managed with large-size cutblocks in even-aged plantations, thereby producing early-successional vegetation areas that are also colonised by the species. Farmland and open areas in forests create mosaics of two different types of habitats that are now occupied by the shrikes. We examined redundant measures of habitat preference (order of settlement after migration and distribution of dominant individuals) and several reproductive performance parameters in both habitat types to investigate whether habitat preference is in line with habitat quality. Territorial males exhibited a clear preference for the recently created open areas in forests with higher-quality males settling in this habitat type earlier. Reproductive performance was, however, higher in farmland, with higher nest success, offspring quantity, and quality compared to open areas in forests. The results showed strong among-year consistency and we can therefore exclude a transient situation. This study demonstrates a case of maladaptive habitat selection in a farmland bird expanding its breeding range to human-created open habitats in plantations. We discuss the reasons that could explain this decision-making and the possible consequences for the population dynamics and persistence

Bird tolerance to humans in open tropical ecosystems

AbstractAnimal tolerance towards humans can be a key factor facilitating wildlife–human coexistence, yet traits predicting its direction and magnitude across tropical animals are poorly known. Using 10,249 observations for 842 bird species inhabiting open tropical ecosystems in Africa, South America, and Australia, we find that avian tolerance towards humans was lower (i.e., escape distance was longer) in rural rather than urban populations and in populations exposed to lower human disturbance (measured as human footprint index). In addition, larger species and species with larger clutches and enhanced flight ability are less tolerant to human approaches and escape distances increase when birds were approached during the wet season compared to the dry season and from longer starting distances. Identification of key factors affecting animal tolerance towards humans across large spatial and taxonomic scales may help us to better understand and predict the patterns of species distributions in the Anthropocene.</jats:p

Animals of different phenotype differentially utilise dietary niche- the case of the Great Grey Shrike Lanius excubitor

We tested the morphological trait utility in Great Grey Shrike Lanius excubitor. The food composition was used as an indicator of phenotype performance advantage in utilising of particular dietary niche. Mounts and accompanying data (measurements and stomach contents) from the Slovak extensive collection, involving adult birds obtained from April to October, were selected for analysis (n = 48). Ordination methods (redundancy analysis) and Generalized Linear Model regression show that the composition of the bird's food was non-random in respect to body characteristics. Tarsus and wing lengths were the most important morphometric predictors and ex- plained 12.7% of overall variance in food data. Smaller birds foraged mainly on Carabidae. Individuals with longer wings and tails more frequently preyed on flying and plant-dwelling insects. We conclude that phenotypic characteristics of an animal at least partially determine its diet

SSAP markers based on a novel Ty1-copia like element are a powerful tool for the assessment of genetic diversity in rye (Secale cereale L.) inbred lines

A partial sequence of a Ty1-copia retrotransposon was isolated from the genome of the rye (Secale cereale L.) inbred line L318 using degenerate primers targeted at the RNaseH sequence. Its putative 3’LTR region exhibited similarity to LTRs of known plant retrotransposons such as BARE-1, while no significant similarity to known rye retrotransposon sequences was found. A Sequence Specific Amplification Polymorphism (SSAP) protocol employing primer designed to correspond to the putative polypurine tract was developed and used for analysis of 30 rye inbred lines. Values of the parameters calculated to evaluate the efficiency of the method as well as the results of cluster analysis demonstrate that it is a powerful tool for genetic diversity analyses of rye

Addition of Dried Blood Plasma to Feed of Minks During Lactation and Rearing of Kits

Studies on the effects of dried blood plasma on certain health parameters of mink (of the pastel variety) were conducted during lactation and the rearing of the kits. The study included two groups of mink (control group and experimental group). Animals in the experimental group received 0.5 % of dry blood plasma and the control group did not receive the plasma supplement. From the whole blood of both groups the direct and indirect haematological indices were recorded. Also, in both groups, the histopathological and immunohistochemical studies were performed on the: liver, kidneys, lymph nodes, spleen, and intestinal segments. From the experimental group some of the organs examined demonstrated slightly altered histopathology

Where Has All Our Research Gone? A 20-Year Assessment of the Peer-Reviewed Wildlife Conservation Literature

We conducted a review of the wildlife conservation literature to identify broad trends in the publishing record and focal areas of research over the past 20 years. A total of 5,853 papers were reviewed with an emphasis on decadal changes between 1993, 2002, and 2012. For each paper we identified the journal and common keywords, and also determined the research scope, conservation issues and applications, and geographic focus. We found that both the number of journals publishing in the field, as well as the number of published articles, has increased significantly over time. The proportional contribution of the most prominent journals in the field has decreased over time, but not the importance of the articles within those journals. Previously reported biases in the literature towards mammals and birds, persisted in our study, leaving large proportions of globally threatened taxa (e.g. amphibians) underrepresented. There was also a disparity in the number of publications from particular geographic regions, however, the proportional contribution of under-represented geographic regions (e.g., Central &amp; South America) increased over time. Finally, using the prevalence of keywords, we identified wildlife/adaptive management, hunting/bushmeat, and human wildlife conflict as contemporary (1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012) research priorities. The persistence of biases towards charismatic taxa can hinder conservation efforts, and we suggest that researchers refocus their efforts towards vulnerable regions and taxa in order to better address conservation priorities