Every time you bird your favorite birding area, you add to the accuracy of the bird list in that location. Additionally, you increase accuracy of frequency and abundance for the county, state, and country.
Other ideas for repeated bird counts:
Keep track of birds out the window at your bird feeder for 10 or 15 minutes, and do so several times during same day. Each time you look is a different stationary count.
Occasionally, I take the dog for a 20 minute walk around the neighborhood on the same route.
Get out of the office! Take a lunchtime walk at work and keep track of what you see.
If you have a special place that you bird every week or more often, then you may want to consider a special eBird Site Survey.
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