Look up "pareidolia".
You have to consider, if this was carved by someone, how were they able to get the fine detail done? These were not done by artisans but by clerks or postmasters that were not necessarily artistic or good designers, and were likely just using a standard pocketknife. Use an easily carved soft/too soft wood and the cancel would last a few days at best.
So, what is this one?
image from Cole
Cole says this is a swan, used at Northampton, Mass. Okay... Turn it 45 degrees. The actual size is about that of a whole Banknote stamp. I've seen a couple of these in scans or real life, but the strikes were just bad enough that if I didn't know this one, I would have thought it to be a freeform ink blob otherwise. And none were oriented right side up, either.
Why don't I think pareidolia is at work here? Because this is another Northampton cancel used from a year or less away:
Now that looks like a swan. Size of cancel unknown, image also from Cole.
This also brings up a second problem of identifying fancy cancels. The outline pictures in reference books are generally tracings and seem to be composites often enough. In any case, they do not necessarily match ones I've seen in scans or real life. I'm guessing based on existing date gaps that there may be similar designs made by the same clerk or postmaster and some of the book illustrations are based on composites rather than similar but distinct designs. Also, wear over time can cause unexpected distortion. Put the eBay
sellers that are often really bad at identifying fancy cancels by Cole or other references into the mix and everything gets even more muddled.