Because your pivot table gives identical Easting/Northing
values to all species, and because the presence/absence
data that distinguishes species is missing in your ggplot
code.
Does this give you what you're looking for?
#plotting scatterplots
ggplot(
df.piv |>
# include only species present at each site
filter(`presence/absence` == 1)
) +
geom_point(aes(x=Easting,y=Northing)) +
facet_wrap(~Species) +
theme_bw() +
ylab("Northing")+ xlab("Easting")
Created on 2024-01-19 with reprex v2.0.2