---
title: Supplementary material
date: last-modified
format: 
  html:
    html-table-processing: none
    toc: true
---

# S1 Effort

::: {.callout-important}
Note logarithmic colour scale!
:::

![Survey effort in km ship transect per European 10 $\times$ 10 km reference grid cell together with the German Exclusive Economic Zone. Note logarithmic colour scale.](../figures/map_effort.svg)

![Survey effort in km ship transect per day of the year.](../figures/pheno_effort.svg)

# S2 Observation data

::: {.callout-important}
Note logarithmic colour scale!
:::

![Map showing the total number of observed individuals per 10 $\times$ 10 km reference grid cell. Note logarithmic colour scale.](../figures/map_raw.svg)

```{r setup, include=FALSE}
library(dplyr)
library(gt)

o <- read.csv("../results/overview.csv") |>
  mutate(Species = paste0(Species, " *", Name, "*")) |>
  select(-Name)
```

```{r}
#| label: tbl-data
#| tbl-cap: Observation data for all observed taxa in the North and Baltic Sea, reporting the migration type, the number of observations, total individual counts, and maximum flock size (Max).
o |>
  gt(groupname_col = "region", row_group_as_column = TRUE) |>
  fmt_markdown() |>
  tab_options(table.font.size = 12)
```

# S3 Abundance throughout the year

![Animated daily maps of songbird migration intensity across the German North Sea (west) and Baltic Sea (east). For each day of the year, posterior predictions are displayed for every European 10 $\times$ 10 km reference grid cell and expressed as the number of birds observed per 100 km of ship transect. The German EEZ is outlined in thin black.](../figures/map.gif)

# S4 Most common species

::: {.callout-important}
Note different colour scales!
:::

![](../figures/map_Barn%20swallow.svg)

![](../figures/map_Eurasian%20skylark.svg)

![](../figures/map_European%20starling.svg)

![Abundance maps of songbird migration intensity for the four most common species across the German North Sea (western portion of the map) and the Baltic Sea (eastern portion), derived from ship-based survey data. Posterior predictions represent species-specific peak autumn migration for each European 10 $\times$ 10 km reference grid cell, expressed as the number of birds observed per 100 km of ship transect. Note different colour scales.](../figures/map_Meadow%20pipit.svg)

![Relationship between distance to the coast and migration intensity, measured as the number of songbirds observed per 100 km ship transect for the four most common species. Curves show 100 posterior predictions for expected outcome values, the locations of Helgoland and Dogger Bank are indicated for reference. Note that the y-axis is scaled logarithmically.](../figures/dist_to_coast_sp.svg)

# S5 Daytime and nighttime migrants

::: {.callout-important}
Note different colour scales!
:::

![](../figures/map_day.svg)

![Abundance maps of songbird migration intensity for daytime (upper) and nighttime (lower) migrants across the German North Sea (western portion of the maps) and the Baltic Sea (eastern portion), derived from ship-based survey data. Posterior predictions represent peak autumn migration for each European 10 $\times$ 10 km reference grid cell, expressed as the number of birds observed per 100 km of ship transect. Note different colours scales.](../figures/map_night.svg)

![Relationship between distance to the coast and migration intensity, measured as the number of songbirds observed per 100 km ship transect for daytime and nighttime migrants. Curves show 100 posterior predictions for expected outcome values, the locations of Helgoland and Dogger Bank are indicated for reference. Note that the y-axis is scaled logarithmically.](../figures/dist_to_coast_groups.svg)