Comparing the reporting rates of species between SABAP1 and SABAP2 is a very useful exercise when investigating range change and abundance change. For this reason, we have introduced an online tool that allows you to research these changes.
However, it is very important to understand the key differences between SABAP1 and SABAP2 in order to understand what the data means. The data indicates a direct comparison between the reporting rates (the percentage of cards the species was recorded on) of the species between the two projects. No attempt has been made to account for differences in effort.
The most important difference to understand between SABAP1 & 2 is the differences in the survey protocol employed by the two projects. SABAP1 (1981-1998) had a far looser protocol, with cards being un-ordered lists, including observations over a range of 1 up to 30 days. The spatial unit surveyed was a Quarter Degree Grid Cell (0°15' x 0°15' or 0.25 degrees x 0.25 degrees). There was also no measure of true effort associated to the surveys.
SABAP2 (2007 – present) introduced a much more rigorous protocol, where effort is measured in hours atlasing, and the spatial resolution is smaller (‘pentad’ 0°05' x 0°05' or 0.8667 degrees x 0.8667 degrees). Each SABAP2 full protocol survey ranges from a minimum of 2 hours to a maximum of 5 days (or 120 hours). Atlasers also log the species in the order (sequence) in which they are observed and keep cumulative hourly totals for each survey. For more information on the SABAP2 protocol see the How to section.
Please bear this in mind when analysing the data.
include coverage on map
|Relative change in Reporting rate|
|50 - 100%|
|25 - 50%|
|10 - 25%|
|5 - 10%|
|0.001 - 5%|
|-0.001 - (-5)%|
|(-5) - (-10)%|
|(-10) - (-25)%|
|(-25) - (-50)%|
|(-50) - (-100)%|
|Insufficient data (below 4 SABAP2 cards per QDGC)|
The following charts represent the changes in Reporting Rate within the species known range of the region.