Observed adult tertiary sex ratio (proportion of all adult birds that were males) of birds captured in mist nets in relation to level of background radiation (µSv/h) during 2010–2011. Error bars represent standard errors.

<p>Observed adult tertiary sex ratio (proportion of all adult birds that were males) of birds captured in mist nets in relation to level of background radiation (µSv/h) during 2010–2011. Error bars represent standard errors.</p

Proportion of birds with sperm in relation to background radiation level (µSv/h).

<p>Proportion of birds with sperm in relation to background radiation level (µSv/h).</p

Map of background radiation (µSv/h) in the Chernobyl region and location of the study sites.

<p>Adapted from European Union <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0100296#pone.0100296-European1" target="_blank">[77]</a>.</p

Age ratio (% yearlings), sample size and difference between adult survival rate and adult survival rate estimate based on age ratio (100 - % yearlings) for areas with normal (< 0.05 µSv/h) and higher levels of background radiation ((≥ 0.05 µSv/h) during 2010–2011.

<p>Northern Ukraine has low levels of background radiation around 0.01–0.05 µSv/h in areas that are unaffected by contamination from Chernobyl <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0035223#pone.0035223-Shestopalov1" target="_blank">[25]</a>. The null expectation for difference in survival rate is zero, while the predicted difference is expected to be zero for normal background radiation, but a significantly lower difference survival rate at higher levels of background radiation.</p

Box plots of background radiation level (µSv/h) for birds without and with sperm.

<p>Values are medians, quartiles, 5- and 95-percentiles and extreme values.</p

Generalized linear mixed models of the relationship between three principal components of sperm behavior and radiation, species×radiation and year.

<p>The random species effects were as follows: PC1: variance component 0.585, 95% CI = 0.1081, 1.0612, accounting for 21% of the variance. PC2: variance component 0.360, 95% CI = 0.0694, 0.6501, accounting for 24% of the variance. PC3: variance component 0.095, 95% CI = −0.0631, 0.2533, accounting for 7% of the variance.</p

Absence of sperm in relation to level of background radiation (model 1) and level of background radiation, keel length and body mass (model 2).

<p>The models had the statistics χ² = 68.74, d.f. = 2, <i>r</i>² = 0.15, <i>P</i><0.0001 and χ² = 81.44, d.f. = 4, <i>r</i>² = 0.18, <i>P</i><0.0001.</p

Observed age ratio (proportion of all birds that were yearlings) of birds captured in mist nets in relation to level of background radiation (µSv/h) during 2010–2011. Error bars represent standard errors.

<p>Observed age ratio (proportion of all birds that were yearlings) of birds captured in mist nets in relation to level of background radiation (µSv/h) during 2010–2011. Error bars represent standard errors.</p

DataSheet1_Diet and disturbance: Seaside Sparrow resource use driven by oiling and Hurricane Isaac.docx

The 2010 Deepwater Horizon (DWH) disaster led to extensive oil deposition in Louisiana’s coastal wetlands, followed two years later by Hurricane Isaac. These disturbances led to changes in saltmarsh invertebrate communities, potentially affecting higher-level predators and the saltmarsh food web. Seaside Sparrows (Ammospiza maritima) are ubiquitous, year-round residents of the coastal saltmarsh affected by the DWH spill, where they consume diverse invertebrates and may be considered an indicator species for the ecosystem’s integrity. We used DNA metabarcoding to evaluate prey consumed by Seaside Sparrows to understand how sparrows responded to residual contamination from the DWH oil spill and ecosystem disturbance caused by Hurricane Isaac. To do so, we evaluated metrics of diet (prey richness, diversity, overall diet composition) and resource use (total niche width, individual specialization) from 2011 to 2017 on oiled, unoiled, and reference sites. We found that while diet composition varied across years and site type, Hurricane Isaac had an even greater effect on the richness and diversity of prey consumed. Resource use—as measured by the total niche width of the populations and degree of individual specialization—was most stable on unoiled sites compared to unoiled and reference sites. Finally, we analyzed resource use for each combination of site type and year (i.e.: “2014 oiled sites”), which indicated a strong correlation between individual specialization and total niche width: as total niche width increased, individuals became more specialized, following the predictions of the Niche Variation Hypothesis.</p

Survival of barn swallows in relation to antioxidant capacity (AOC; mmol l⁻¹ of HClO neutralised).

<p>Survival functions were fitted to data stratified according to individuals being of low (< population mean −1 Standard Deviation), intermediate (comprised between mean −1 SD and mean +1 SD), or high (> mean+1 SD) AOC. This analysis differs from that presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0019593#pone-0019593-t001" target="_blank">Table 1</a> and was performed to allow representation of the association between AOC and survival.</p