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Misteln wachsen auf Ästen und Zweigen von Laub- und Nadelbäumen. Typische Wirtsbäume der Laubholzmistel sind in Mitteleuropa Apfel oder Pappel. Die Besiedlung eines Wirtsbaumes ist ein Zusammenspiel zwischen Eigenschaften des Wirtsbaumes, des Parasiten und seiner Vektoren, im Fall der Mistel von beerenfressenden Vögeln (Zoochorie). Per Vogel erreicht die Mistel geeignete Äste in Baumkronen, die ein erfolgreiches Keimen und Wachsen ermöglichen. Samen verbreitende Drosseln profitieren andererseits von der Beerennahrung in einem von ihnen ausgesuchten, sicheren Ausguck. Aber Misteln breiten sich auch durch „Abtropfen“ innerhalb befallener Bäume aus. Wenn sich die reifen Beeren öffnen, entleert sich das Mesokarp mit den von Viscin und Cellulose überzogenen Samen. Diese Naturstoffe sind von hoher Klebrigkeit und bilden 15 bis 20 Zentimeter lange stabile Fäden, an denen die Samen kleben. Solche Mistelschnüre baumeln im Winter zahlreich aus den Mistelbüschen herab und fallen entweder auf tiefer gelegene Strukturen oder der Wind verdriftet sie in die Umgebung. Offenbar trägt zumindest in manchen Regionen diese Schnur-Wind-Verbreitung zur effektiven Ausbreitung von Misteln innerhalb ihrer Wirtsbäume und deren Nachbarbäume bei. Mistelschnüre ermöglichen eine Vogel-unabhängige Ausbreitung., Mistletoe grows on the twigs and branches of deciduous and coniferous trees. Typical deciduous hosts in central Europe are apple and poplar trees. The colonisation of a host tree is an interactive process between the innate characteristics of the host tree and the parasite with its vectors, in this case berry-eating (frugivore) birds (zoochory). The mistletoe is placed by birds on a suitable branch within the crown of a tree thus enabling a successful germination and growth. In turn, thrushes dispersing mistletoe seeds profit from the berry food in a safe lookout chosen by them. However, mistletoe also disperse by „dripping down“ from infested/parasitized trees. When the ripe berries of the mistletoe open, the mesocarp releases the seeds coated with cellulose and viscin. The latter is a natural substance that is very sticky and forms 15 to 20 cm long threads to which the seeds stick. During winter, these mistletoe threads dangle from the mistletoe bushes and either drop down onto lower branches or are dispersed by the wind. In some regions, this thread-wind-dispersal apparently contributes to the effective spreading of mistletoe within their hosts and their neighbouring trees. Thus, mistletoe threads enable a form of dispersal independent of birds.

Misteln wachsen auf Ästen und Zweigen von Laub- und Nadelbäumen. Typische Wirtsbäume der Laubholzmistel sind in Mitteleuropa Apfel oder Pappel. Die Besiedlung eines Wirtsbaumes ist ein Zusammenspiel zwischen Eigenschaften des Wirtsbaumes, des Parasiten und seiner Vektoren, im Fall der Mistel von beerenfressenden Vögeln (Zoochorie). Per Vogel erreicht die Mistel geeignete Äste in Baumkronen, die ein erfolgreiches Keimen und Wachsen ermöglichen. Samen verbreitende Drosseln profitieren andererseits von der Beerennahrung in einem von ihnen ausgesuchten, sicheren Ausguck. Aber Misteln breiten sich auch durch „Abtropfen“ innerhalb befallener Bäume aus. Wenn sich die reifen Beeren öffnen, entleert sich das Mesokarp mit den von Viscin und Cellulose überzogenen Samen. Diese Naturstoffe sind von hoher Klebrigkeit und bilden 15 bis 20 Zentimeter lange stabile Fäden, an denen die Samen kleben. Solche Mistelschnüre baumeln im Winter zahlreich aus den Mistelbüschen herab und fallen entweder auf tiefer gelegene Strukturen oder der Wind verdriftet sie in die Umgebung. Offenbar trägt zumindest in manchen Regionen diese Schnur-Wind-Verbreitung zur effektiven Ausbreitung von Misteln innerhalb ihrer Wirtsbäume und deren Nachbarbäume bei. Mistelschnüre ermöglichen eine Vogel-unabhängige Ausbreitung., Biologie in unserer Zeit, Early View

Timber harvesting practises can lead to loss of suitable nesting opportunities and thus have a negative impact on reproductive success and abundance of arboreal species. For many species, the impact of forest operations and the effectiveness of mitigation, such as pre-operational surveys, re-tention of trees with nests or the use of nest boxes, are unknown. This study aimed to assess the impact of forest operations and the utility of nest boxes as a conservation tool, using the Eurasian red squirrel (Sciurus vulgaris) as study species. We carried out the first quantitative assessment of drey survey effectiveness and tested the predictions that (1) red squirrel drey use increases post-thinning (2) nest box use increases post-thinning when their availability may be critical; (3) nest box use increases over time due to habitation and (4) nest box characteristics and placement affect nest box use. Our results show that thinning has led to squirrels changing their nesting behaviour with increased drey use post forest operations. We conclude that drey surveys are inefficient due the dynamic nature of drey use by red squirrels and that although foresters can detect a small pro-portion of active dreys, it is impossible to assess whether dreys are in use. Furthermore, nest box use increased after forest operations and nest boxes placed at a lower position in the tree were pre-ferred. Our results suggested that red squirrels habituate to nest boxes over time as nest box use was higher during the second year after deployment. Overall, we propose that nest boxes can be a useful conservation tool to mitigate the impacts of forest operations and conclude that early deployment of nest boxes can contribute to red squirrel conservation by providing shelter for red squirrels after forest operations – and potentially for juveniles during natal dispersal.

Additional file 5. Maximum likelihood tree analysis of polyomaviruses based on conserved amino acid blocks of the VP1 sequences. Phylogenetic relationships of polyomaviruses, including classification of the novel viruses, based on conserved amino acid blocks of VP1 sequence. Branch support values displayed at the nodes were assessed using Shimodaira-Hasagawa-like approximate likelihood ratio tests (SH-like aLRT). For further details see legend of Fig. 3.

Additional file 2. Flow chart of multi-level PCR analysis for detection of squirrel polyomaviruses. Generic nested VP1 PCR (second-round product displayed as magenta-coloured bar) with degenerate primers was conducted. For full genome amplification, this was followed by specific nested long-distance PCR (LD-PCR; second-round product of approximately 5 kbp shown as red bar) and overlapping standard nested PCR (second-round product of approximately 800 bp shown as green bar) with specific primers. Grey bars represent coding sequences, black bar the non-coding control region.

Additional file 4. Maximum clade credibility tree analysis of polyomaviruses based on conserved amino acid blocks of the LTAg sequences. Phylogenetic relationships of polyomaviruses, including classification of the novel viruses, based on conserved amino acid blocks of LTAg sequence. Branch support values displayed at the nodes correspond to their posterior probability. For further details see legend of Fig. 3.

Additional file 10. Maximum clade credibility tree analysis of gammaherpesviruses based on conserved amino acid blocks of the DPOL sequences. Phylogenetic relationships of gammaherpesviruses, including classification of the novel viruses, based on conserved amino acid blocks of DPOL sequence. Branch support values displayed at the nodes correspond to their posterior probability. For further explanation see legend of Fig. 5.

Additional file 9. Maximum clade credibility tree analysis of betaherpesviruses based on conserved amino acid blocks of the gB sequences. Phylogenetic relationships of betaherpesviruses, including classification of the novel viruses, based on conserved amino acid blocks of gB sequence. Branch support values displayed at the nodes correspond to their posterior probability. For further explanation see legend of Fig. 4.