Sampling localities of <i>Sciurus vulgaris</i> in France.

<p>Locations of the centroide of our sampling sites are indicated in black points, <i>n</i> indicates the number of specimens analysed in each locality.</p

Summary Statistics of molecular variation and neutrality tests in nine <i>S. vulgaris</i> European populations.

*<p>, significant at the 0.05 level;</p>**<p>, significant at the 0.01 level.</p>***<p>, significant at the 0.001 level.</p><p>In order to be able to compare values between populations, the 252 pb fragment analyzed by Grill, <i>et al.</i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0047607#pone.0047607-Sidorowicz1" target="_blank">[11]</a> was used for all samples. It corresponds to the positions 1–252 of the fragment analyzed in previous studies <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0047607#pone.0047607-Ogden1" target="_blank">[16]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0047607#pone.0047607-Barratt1" target="_blank">[17]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0047607#pone.0047607-Hale1" target="_blank">[18]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0047607#pone.0047607-Hale2" target="_blank">[19]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0047607#pone.0047607-Finnegan1" target="_blank">[20]</a> and to the positions 111–362 of the fragment analyzed in the present study.</p

Mismatch distribution for the 110 French <i>Sciurus vulgaris</i> D-loop haplotypes (516 bp).

<p>The Mismatch distribution is the distribution of the number of pairwise differences among sequences. The expected distribution under a model of population expansion is given as a continuous line, and the observed distribution is given as a dashed line.</p

Maximum likelihood tree of French and European <i>Sciurus vulgaris</i> D-loop haplotypes (252 bp).

<p>Bootstrap values are shown as percentage of 1000 replicates at each node only if they are 50% or greater. The numbers of identical haplotypes per locality are indicated in brackets. Abbreviations indicate the geographical origin of French samples : Aq: Aquitaine Midi Pyrénées; Bn: Basse Normandie; Br: Bourgogne; Fc: Franche Comté; Hn : Haute Normandie; If : Ile-de-France; Lc : Lorraine Champagne; Mc : Massif Central; Pl : Paca Languedoc-Roussillon; Ra : Rhône Alpes.</p

Mandible descriptors and PCs for comparison

Sheet 1: Mandible area and Fourier coefficients from A0 to B7 describing size and shape of the mandible. Sheet 2: Mechanical advantages (MAs) and axes for comparisons: PCclimate, PC for D-loop analysis, and PC for mitochondrial analysis

A Viable Population of the European Red Squirrel in an Urban Park

<div><p>Whether urban parks can maintain viable and self-sustaining populations over the long term is questionable. In highly urbanized landscapes, urban parks could play a role in biodiversity conservation by providing habitat and resources to native species. However, populations inhabiting urban parks are usually small and isolated, leading to increased demographic stochasticity and genetic drift, with expected negative consequences on their viability. Here, we investigated a European red squirrel population located in an urban park close to Paris, France (Parc de Sceaux; 184 ha) to assess its viability. Using mitochondrial D-loop sequences and 13 microsatellite loci, we showed that the population presented high levels of genetic variation and no evidence of inbreeding. The size of the population was estimated at 100–120 individuals based on the comparison of two census techniques, Distance Sampling and Capture-Mark-Recapture. The estimated heterozygosity level and population size were integrated in a Population Viability Analysis to project the likelihood of the population's persistence over time. Results indicate that the red squirrel population of this urban park can be viable on the long term (i.e. 20 years) for a range of realistic demographic parameters (juvenile survival at least >40%) and immigration rates (at least one immigration event every two years). This study highlights that urban parks can be potential suitable refuges for the red squirrel, a locally threatened species across western European countries, provided that ecological corridors are maintained.</p></div

Results of simulations run for the population viability analysis of red squirrels population of the Parc de Sceaux.

<p>Results of simulations run for the population viability analysis of red squirrels population of the Parc de Sceaux.</p

Map of the Parc de Sceaux showing the distribution of line transects, traps, and woody areas suitable to red squirrels.

<p>Map of the Parc de Sceaux showing the distribution of line transects, traps, and woody areas suitable to red squirrels.</p

Phylogeny of <i>virB5</i> gene sequences using Maximum likelihood, with a GTR substitution model.

<p>Clusters in which <i>virB5</i> alleles were found are indicated by colors and shapes identical to <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0068956#pone-0068956-g001" target="_blank">Figure 1</a> (see legend). Bootstrap values higher than 80% are given at the nodes. Arrows indicate <i>virB5</i> sequences amplified and sequenced from strains obtained from wood mice.</p

Schema of our approach to modelling interaction.

<p>Schema of our approach to modelling interaction.</p