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Photo © Al Tuttle

What are some common data entry mistakes?

Sometimes, monitors make mistakes when entering data. Read on to avoid some common pitfalls:

  • Creating a new nest site for every year/breeding season. You are already entering dates for each of your nest visits, so you can re-use the same nest site year after year, as long as that box/site has not been moved or taken down.
  • Recording too many visits. Nest checks should be made every 3-4 days at most. For a typical songbird nest, this equates to about 10 checks per nest attempt. Read more tips in our Code of Conduct. If you have a camera on a nest, it is okay to report once a day as long as the birds are not disturbed.
  • Making a new attempt for every nest visit. Some monitors have mistakenly started a new nesting attempt for each time they visit the nest, rather than adding all their nest visits under one nesting attempt. Remember, the nest attempt should be a record of one clutch of eggs from start to finish. Review the data structure here.
  • Adding data from more than one clutch of eggs in a single nest attempt. Do not add data from more than one clutch to your nest attempt record. For example, if your first clutch of eggs disappears before they hatch, and then on your next nest visit you see several eggs, you should summarize the attempt with the appropriate outcome for that first clutch (a failed attempt). Then, start a new nest attempt to report on the new clutch, even if you think the new clutch has been laid by the same bird. Similarly, do not add together multiple nests into one attempt (e.g., 4 eggs in Box 1 plus 5 eggs in Box 2 = 9 eggs). In NestWatch, each nest gets reported separately.
  • Entering the first egg date. A few people have entered the wrong date in the nest summary when asked for the “First Egg Laid Date.” If you accidentally put down the first day of incubation, you can easily count back to the day the first egg was laid, because birds generally lay one egg per day, and incubate almost immediately after the last egg is laid. Remember, this question is about the first date on which an egg was laid, NOT the first date which you saw an egg (e.g., you might not see the eggs until well after the first egg is laid).
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Cornell Lab of Ornithology

Cornell Lab of Ornithology