Species Frequency Maps provide insight into species population patterns geographically and chronologically. In comparison to the Ohio Species Distribution Maps, which depicts the most recent observation of each species on a county by county basis, the maps on this page depict the number of observations of each species on a county by county basis. The county data depicted here is meant to be a sort of heat map, providing insight into each species’ relative population in each Ohio county. The bar chart provides depicts the species observation frequency across the most recent 25 years, providing insight into the overall population of each species, and the degree to which it might be increasing or declining in population.
This data is significantly impacted in multiple ways by observation bias, but given the hundreds of thousands of odonata observations tracked by the OOS survey, and the lack of any other mechanism useful for measuring odonata population, it is reasonable to treat this form of information as a useful proxy for the actual geographic and chronological distribution of our damselfly and dragonfly species.
There’s room here for a bar chart showing the number of observations in each of the last 25 years. I think that would be useful in helping people normalize the bar charts within their brains.
