Natremia (plasma sodium concentration) of thirteen free-ranging individual <i>N. tessellata</i> captured at Poda Protected Area, Bulgaria.

<p>The dashed lines indicate the range of normonatremia (130–160 mmol.l⁻¹<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Campbell1" target="_blank">[45]</a>) and the horizontal black line indicates mean normonatremia (145 mmol.l⁻¹). For clarity, individuals are ranked by ascending order of natremia.</p

Map of the study area.

<p>The upper panel gives the location of the Poda Protected Areas in the vicinity of Bourgas, Bulgaria. Emergent lands are indicated in white, water is indicated in light grey. The lower panel shows the Poda Protected Area (dashed area). Emergent lands are indicated in white and water is indicated in light grey. Numbers designate salinity (‰) recorded for three ponds, two locations on the shore of the Black Sea, and one location at the mouth of the Mandra Lake. The two arrows show sites where tracks from snakes commuting between the land and the Black Sea were observed.</p

Published data on snake natremia.

<p>These data were available from strictly fresh water species (<i>Nerodia fasciata</i> and <i>N. sipedon </i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Babonis2" target="_blank">[24]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Dunson9" target="_blank">[26]</a>), salt tolerant species lacking salt glands (<i>N. clarckii clarckii</i>, <i>N. clarckii compressicauda</i>, <i>Thamnophis valida </i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Babonis2" target="_blank">[24]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Dunson9" target="_blank">[26]</a>), amphibious sea kraits with functional salt glands (<i>Laticauda saintgironsi</i>, <i>L. laticaudata</i>, <i>L. semifasciata </i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Babonis2" target="_blank">[24]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Brischoux3" target="_blank">[25]</a>) and fully marine sea snakes with functional salt glands (<i>Acrochordus granulatus</i>, <i>Hydrophis elegans</i>, <i>H. cyanocinctus</i>, <i>Pelamis platurus </i><a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Dunson4" target="_blank">[18]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Dunson5" target="_blank">[19]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Dunson7" target="_blank">[21]</a>–<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Duggan1" target="_blank">[23]</a>. The dashed lines indicate the range of normonatremia (130–160 mmol.l⁻¹<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0092617#pone.0092617-Campbell1" target="_blank">[45]</a>) and the horizontal black line indicates mean normonatremia (145 mmol.l⁻¹). Numbers above the bars indicate survival rates (no number  = 100%). Data are mean values per species ± SD.</p

Sampling of “priority protection species”.

<p>The adequacy of sampling was based on richness estimator (Chao estimator) for the internet (raw and adjusted, N = 236 samples; see text for details) and schoolchildren (raw and adjusted, N = 250 samples; see text for details). All the curves reached a plateau, indicating that we adequately sampled the diversity of “priority protection species” both for the internet and for schoolchildren.</p

Local vs. exotic biodiversity.

<p>Proportion of exotic (grey bars) and local (black bars) species for which live specimens have been seen/observed by schoolchildren (“Species observed”), that were successfully identified by schoolchildren (“Species identified”) and that were perceived as “priority protection” by schoolchildren (“Priority protection species”). See text for details.</p

Mean ± SE (A) fat and (B) muscle scores of sparrows captured in 4 sites with different levels of urbanization.

<p>Sites are ordered from least to most urbanized (PC1 values) with two rural (CEBC and Villefollet) and two urban sites. Filled circles represent adults and open circles represent juveniles (n = 110, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135685#pone.0135685.t002" target="_blank">Table 2</a> for details). Differing letters indicate statistical difference between sites for juveniles only (A) or for both adults and juveniles (B) (Tukey’s HSD test).</p

Minimum adequate models when investigating the influence of capture site on several morphological parameters.

<p>Models were selected by using a stepwise approach starting from the full models (including site, age, sex, and interactions) and removing independent variables with P > 0.10.</p><p>Minimum adequate models when investigating the influence of capture site on several morphological parameters.</p

Mean ± SE (A) tarsus lengths and (B) body mass of sparrows captured in 4 sites with different levels of urbanization.

<p>Sites are ordered from least to most urbanized (PC1 values) with two rural (CEBC and Villefollet) and two urban sites. Filled circles represent adults and open circles represent juveniles (n = 110, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135685#pone.0135685.t002" target="_blank">Table 2</a> for details). Differing letters indicate statistical difference between sites for both adults and juveniles (Tukey’s HSD test).</p

Mean ± SE scaled mass index values of (A) adult and (B) juvenile sparrows captured in 4 sites with different levels of urbanization.

<p>Sites are ordered from least to most urbanized (PC1 values) with two rural (CEBC and Villefollet) and two urban sites. Filled circles represent adults and open circles represent juveniles (n = 110, see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0135685#pone.0135685.t002" target="_blank">Table 2</a> for details). The SMI did not significantly differ between sites as indicated by the similar letters (Tukey’s HSD test).</p

Minimum adequate models when investigating the influence of capture site on several physiological parameters.

<p>Models were selected by using a stepwise approach starting from the full models (including site, age, sex, time, time² and interactions) and removing independent variables with P > 0.10.</p><p>Minimum adequate models when investigating the influence of capture site on several physiological parameters.</p