Pokemon-go – Total stardust doesn’t refresh at first power up. Is this a bug

The Silph Road has done quite a bit of research into spawning mechanisms and their findings have been corroborated by much of the community. It isn't necessarily guaranteed to be 100% accurate but the evidence supporting it is overwhelming. In either case, all their work is reproducible and peer-reviewed so it's largely considered to be the most accurate non-official information available.

From what I understand of their findings, the world map is littered with "spawn points" (marked by the rustling grass animations), which spawn one pokemon at regular intervals. Most spawn points trigger once per hour but I've heard of some spawning as often as every half hour (although it is possible that the location simply has two spawn points very close together). A pokemon spawned in this way lasts for 15 minutes before despawning and will be available to any player who is in range during that time. Every spawn location has different timings so one might trigger at :02 past the hour and another might trigger at :29.

I have not yet seen any evidence to suggest that these points may cease spawning at any time for any reason. We do know that they are tied to locations that historically have increased mobile data usage, which is why there are tons in the downtowns of larger cities but very few, if any, out in the country.

Assuming this is all correct, it is theoretically possible to momentarily deplete an area of pokemon by catching everything that is currently spawned but that will only affect you and will only last until the next spawn point triggers.

If I were to speculate, I would say that the "dry area" effect is a description of the 45 minutes per hour that there are no pokemon at a given spawn point. If your area only has one or two spawn points within radar range (especially if they all trigger at roughly the same time), the effect would be highly visible, which is likely what that other user was seeing. I don't know whether the map turning grey is related to this but I would suspect it isn't. Instead, I would chalk that up to a graphical glitch but I don't know that for certain.

I did some timings. I started the time at the white flash and ended it when the actions screen is able to be pressed.

These results aren't comphrehensive but it gives you a good idea. About ~21-22 seconds for a normal evolution and about ~24-26 seconds for a 'new to Pokedex' evolution.

This doesn't seem to be too different from what it was before, but then again I don't know how the person in that answer came up with his numbers.

New to Pokedex Evolution:

Time: 24.05

Pokemon: Staryu to Starmie

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Time: 25.25

Pokemon: Eevee to Flareon

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Normal Evolution:

Time: 21.05 sec

Pokemon: Pidgey to Pidgeotto

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Time: 21.24 sec

Pokemon: Rattata to Raticate

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