Counts of individual birds help eBird's bar charts, abundance graphs, and frequency graphs be more accurate and, in fact, exist at all.
You don't have to be exact. 1, 2, 5, 10, 20, 50, 100, 200, 500, 1000... If you are in the correct order of magnitude, these estimates are better than X, which is what you use when you don't count. [Please remember that X is correct when you don't count. Don't enter 1 for each species when you mean X.]
More information on this topic can be found on the eBird site, The trouble with 'X'.
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