I like that your bucket test matched your pond test. Means you probably do not have a leak.
Surface area of your pond is one of the critical variables for total gallons evaporated. When your pond is full (and almost twice as large) your evaporation rate in gallons per day will be very high.
When your pond loses all of the 1' deep water and shrinks down to its smaller surface size, then your evaporative losses will be much less.
Good info.
I doubt there are significant changes to the watershed for old, well-established ponds. Are the neighbors' ponds that are mostly full upslope of your pond in the same watershed? When you start to get more rains after an extended drought, the upslope ponds will fill first. Only when those ponds begin to pass water through their outlets will your pond start to get more water than just what rain falls on the immediate slopes of your pond.
I attached a topo map that I came across. It appears my pond feeds the neighbors according to the blue lines. Where the blue line starts is a steep dropoff into a 15 foot ravine that levels out as it gets closer to my pond.
I added the yellow line to show where the water comes from. During heavy rains water will pool where I added the white circle. That is where I was thinking of adding a very small cattle tank. But, I guess that would further limit water getting to the pond.
Finally, if you did clear enough trees, then your might have slightly increased the evaporation rate at your pond. My creek is tree lined and in a low spot on the land. Many times it will be calm and humid at the creek, while it is dry and breezy when I work at other parts of the farm. You letting a little more wind reach the surface of your pond might have allowed a little more evaporation. However, in most pond situations, it is beneficial that you cleared the trees. Their roots can steal water from your pond if close enough, and the leaves, pine needles, twigs, etc. cause organic muck to build up on the bottom of the pond and steal some of your depth.
If your pond is mostly full when you go back in time on satellite views, then patience for the rains to get closer to normal may be your best option.
I didn't think about the wind accelerating the evaporation. Suppose all I can do is wait for the rains.
