I think the biodiversity and rate of endemism definitely has some influence on the statistics. I know that at least for myself, the more species in an area the more observations I will make. At least for me, my species repeat percentage remains relatively constant no matter where I observe, with a exponential curve for species in an area and number of species with 2 or more observations. But that is also just my style of using the platform.
Bonap is only for plants but these maps are very helpful in visualizing the potential influence, and could be an entire thread of it’s own
Density Gradient of Native Vascular Plant Species per 10,000 km²
The Wyoming effect shows up again here: US Counties (in blue) with extensive floristic surveys/inventories plus those that house significant plant collections (herbaria/museums)
Density Gradient of “Endemic” (Range Limited <50,000 km²) Plant Species per 10,000 km²
Have fun with the rest of the maps:
http://bonap.org/2015_SpecialtyMaps/Density%20Gradient%202015/Density%20Gradient%202015.html
http://bonap.org/2015_SpecialtyMaps/State%20Flora%20Similarity%202015/State%20Flora%20Similarity%202015%209-21-15.html
http://bonap.org/2015_SpecialtyMaps/