All birders know that not every bird is identifiable. Sometimes you just can't get a good enough look to be sure what it is, or even when you can get a good look, the bird might be a hybrid or otherwise intermediate between two species. These unidentified birds are sometimes called "spuhs." This comes from the abbreviation "sp." for "species," as it was originally used with latin names. For example, "Buteo sp." indicates a hawk that is known to be in the genus Buteo, but it is uncertain which species it is.
Usually unidentified birds are just dismissed - there are plenty more birds that can be identified with certainty. However, when you're doing a listing project like this, it can be important to count every bird. So I've decided to articulate my policy for dealing with spuhs here. I will include spuhs in my species total until I see another bird that could possibly be the same species as the unidentified bird. For example, on the 19th of January I saw a bird that I know certainly was a jay, but I didn't see it well enough to be 100% certain which species. If by the end of the year, I have seen 199 identified species (none of which are jays) and one unidentified jay, then this species will count as number 200. However, as soon as I see another jay that I CAN identify, this spuh disappears from the list because there is a chance that the two birds were of the same species. Therefore, as of today I have seen 83 species: the 81 species listed to the right, plus a jay sp. and a grackle sp. (Spuhs will not be listed in my species list while the list is in progress.) I expect I will be able to find at least one identifiable jay and at least one identifiable grackle, so these uncertain IDs will most likely be absorbed into other, more certain ones by the end of the year.