Probability of snail kite selecting a native or exotic snail.

<p>Model predicted foraging preference (with 95% confidence intervals) of snail kites foraging on native or exotic snails using only the first choice made during experimental trials.</p

Results of conditional logistic regression testing for the effects of various factors on preference using all choices made during a trial.

<p>Results of conditional logistic regression testing for the effects of various factors on preference using all choices made during a trial.</p

Snail kite consumption of native and exotic snails.

<p>The proportion of native (black) and exotic (gray) snails consumed by snail kites between 2004 and 2014 in the (B) Kissimmee Chain of Lakes and the (D) Everglades. Sample sizes are noted in parentheses above each bar. Histograms show the proportion of native (black) and exotic (gray) snails consumed, by size class, in the (C) Kissimmee Chain of Lakes in 2013 (n = 292) and the (E) Everglades in 2014 (n = 813). This species distinction illustrates the expansion of snail sizes made available by the presence of the exotic snail. These data were collected as part of a long-term monitoring program monitoring snail kite demography [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165427#pone.0165427.ref021" target="_blank">21</a>]. During this monitoring effort snail shells were collected opportunistically from snail kite foraging perches within each of the sampling regions. (A) An example of a foraging perch; a cypress tree (<i>Taxodium distichum</i>), with a pile of discarded snail sells underneath. Shell length was measured in the same way that snails were for experiments (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0165427#sec002" target="_blank">Methods</a>). No snail shells were collected in the Everglades in 2008.</p

Choice experiment trial setup.

<p>An example of a two-tray choice experiment trial placed next to a common snail kite foraging perch (<i>Taxodium distichum</i>).</p

Results of conditional logistic regression testing for the effects of various factors on preference using the first choice made during trials.

<p>Results of conditional logistic regression testing for the effects of various factors on preference using the first choice made during trials.</p

Appendix A. Predators of the Blackfoot Valley.

Predators of the Blackfoot Valley

Appendix E. Survival estimates for Spermophilus columbianus during the experiment.

Survival estimates for Spermophilus columbianus during the experiment

The number of eggs laid(least square means + SE) by <i>N. femorata</i> on the basis of social and non-social (resource quality) cues.

<p>Resource quality refers to cactus with cactus fruit (high quality) or without cactus fruit (low quality). Egg numbers are adjusted for female size and effects associated with placement in different areas of the greenhouses. Different letters denote significant pair-wise effects (α = 0.05) based on post hoc multiple comparisons (Tukey-Kramer adjusted <i>P</i>-values).</p

Appendix A. Identification of the best grain size (resolution) for assessing matrix resistance.

Identification of the best grain size (resolution) for assessing matrix resistance

Juvenile <i>Narnia</i><i>femorata</i> (left) and <i>Chelinidea</i><i>vittiger</i> (right) on the same <i>Opuntia</i><i>cactus</i>.

<p>Juveniles form aggregations that can include members of both species.</p