Eight-month cage experiment: Seedling establishment.

<p>Seeds with no cage (Open), cage with small holes that let predators in, but prevent seed transport by hydrodynamics (Open Cage) and seeds protected with cages (Cage C). Different letters above bars denote significant different means (SNK-test at P<0.05). 200 seeds planted per plot. Mean+SE.</p

Seed burial depth and predation.

<p>Seeds consumed per day (mean+SE) by three potential seed predator species as a function of burial depth. Different letters above bars denote significant different means between sediment treatments (SNK-test at P<0.05).</p

Diagram of treatments used in the 1-week field experiment.

<p>a) seeds on the sediment surface (Open), b) seeds covered with sand (Open+S), c) cage with seeds and a shore crab (Cage+P), d) cage with seeds covered with sand and a shore crab (Cage P+S) and e) cage with seeds (Cage C). Seed mimics represented in blue. The figure is not drawn to scale.</p

Seed predation in the laboratory.

<p>Tested sizes for each species (carapace width for <i>C</i>. <i>maenas and P</i>. <i>bernhardus</i>, total length for <i>Palaemon sp</i>., shell length for other species) and biomass (wet weight). Seeds consumed after 24 h, mean+SE, (10 seeds offered).</p

Two-factor ANOVA model testing the proportion of seeds eaten (sqrt-transformed) as a function of seed predator (shore crab, hermit crabs and sea urchins) and burial depth (0, 1, and 2 cm).

<p>Two-factor ANOVA model testing the proportion of seeds eaten (sqrt-transformed) as a function of seed predator (shore crab, hermit crabs and sea urchins) and burial depth (0, 1, and 2 cm).</p

Size of shore crab (<i>C</i>. <i>maenas)</i> and predation of eelgrass seeds.

<p>Size of shore crab (<i>C</i>. <i>maenas)</i> and predation of eelgrass seeds.</p

Summary of species that prey on <i>Z</i>. <i>marina</i> seeds.

<p>nd = no data, b = biomass (g) and b = head width.</p

One-week and one-month cage experiment.

<p>Loss of (a) eelgrass seeds and (b) seed mimics in the one-week, and loss of (c) eelgrass seeds and (d) seed mimics in the one-week. Seeds with: no cage (Open), no cage + sand cover (Open+S), cage + shore crab (Cage P), cage + shore crab + sand cover (Cage P+S) and cage (Cage C). Different letters above bars denote significant different means (SNK-test at P<0.05). 200 eelgrass seeds and 20 seed mimics used per experimental. Mean+SE.</p

Cage experiments.

<p>One-way ANOVA models testing the effect of cage treatments on the loss of natural and seed mimics in 1-week, 1-month and 8-month long field experiments.</p

Estimates of seed losses in the 1-week and 1-month experiments.

<p>Percent loss of eelgrass seeds and mimics in all treatments. Seed losses were estimated by subtracting the losses on each treatment to the losses on the Cage C (to exclude the handling effect, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0168128#pone.0168128.e001" target="_blank">Eq 1</a>). Losses by transport were estimated as the losses of mimics. Losses by predation were estimated as the difference between losses by transport and losses excluding handling. Mean and (Std. Err).</p