KlefothEtAl_data

KlefothEtAl_dat

Seasonal changes in observed migration of roach (number of tagged roach in stream; black line, left y-axes) compared to predictions from seasonal changes in the piscivore consumption/roach growth ratio ((P/G; hatched line, right y-axes) during two years.

<p>Seasonal changes in observed migration of roach (number of tagged roach in stream; black line, left y-axes) compared to predictions from seasonal changes in the piscivore consumption/roach growth ratio ((P/G; hatched line, right y-axes) during two years.</p

A conceptual model for seasonal changes in predation rate by piscivores, growth rate in zooplanktivorous fish and the trade-off, i.e. the ratio of predation and growth, in the lake and stream habitat.

<p>Migrating fish are expected to change habitat so that they minimize the ratio and, thus, migrate from the lake to the stream in autumn and back to the lake in spring, as indicated by arrows.</p

Seasonal development of piscivore consumption rate, growth rate of roach and the ratio between piscivore consumption and roach growth in Lake Krankesjön during 2003/4 and 2004/5.

<p>Seasonal development of piscivore consumption rate, growth rate of roach and the ratio between piscivore consumption and roach growth in Lake Krankesjön during 2003/4 and 2004/5.</p

Grouping of individuals based on observed migration in first (Y1)- and second year (Y2) after tagging and associated potential universal individual migration strategies (UIMS) and survival.

<p>The three UIMS include obligate migrantion (OM), facultative migrantion (FM) and obligate residency (OR). See text for further explanation. <i>N</i> refers to the number of individuals in the different groups in the present study.</p

Mean condition of four groups of individuals based on their residency (N) or migration (Y) during each of the first two years after tagging.

<p>Error bars indicate 95% confidence interval of the mean. Fish that changed from residency to migration (NY) were in significantly lower condition as compared to other groups.</p

Post hoc (tukey HSD) table for ANOVA test of between group difference in somatic condition.

<p>Groups correspond to migration patterns during the first two winters of tagged fish: Yes (Y) and No (N). For further explanation of groups see text and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0090294#pone-0090294-t001" target="_blank">Table 1</a>. Redundant comparisons are removed from the table.</p><p>*The mean difference is significant at the 0.05 level.</p

The effect of somatic condition on the probability of migration in the first winter after tagging for roach migrating at least once in subsequent winters.

<p>A higher somatic condition at the time of tagging increases the likelihood of migration during the first winter after tagging. Circles indicate observed individual participation in migration during the first year after tagging (1: Migration; 0: Residency), whereas line indicate predicted probability of migration based on observed values.</p

Size distribution of all tagged roach in Lake Krankesjön from 2003 to 2007.

<p>Note missing data for fish smaller than 120mm, which were too small to be tagged. As all captured individuals above 125mm were tagged, the data is representative for the general size distribution within the population and consistent with survey data from the lake.</p

Lengths of tow tracks

Length of tow tracks calculated by the APTs and the true trajectory obtained using DGP