Did a person really see six chickadees, or eight? Whether they had the right number of chickadees won't make a difference when you have this much data. It's allowing high-level visualizations of migration distributions, for example, things like that, even though individual records may well have errors. It's a good point, and it's something the scientists who analyze those data think about a lot.
On February 9th, 2023. See this statement in context.