The bird survey data has been collected since 1987. It is divided into 5 year survey periods,
and each year is divided into 48 quarter months.
Below are some graphical summaries of the survey results.
- Species vs Time and Period
A plot of the number of species versus time of
year for the combined survey as well as for each of the three survey periods.
Species vs Time and Survey Combination: A plot of the number of species versus time of year
broken down by the various combinations of survey periods in which records occurred.
Species vs Time and Status: A plot of the number of species versus time of
year broken down in terms of the following categories:-
Year round residents: Occur regularly throughout the year.
Summer residents: Occur regularly through the summer months but not
Winter residents: Occur regularly through the winter months but not
Migrants and vagrants: Fit none of the above categories.
Species vs Time and Family: This plot shows how the family composition of migrants evolves
during migration periods.