That certainly sounds like a nest, albeit a small one. I also have one small nest in my city and it is almost never worth paying a visit because the spawns are so sparse, something like 2 per hour, maybe 3 or 4 if I'm lucky. I only hit that nest when it was a Machop nest, but other than that I just ignore it.
Is this considered a nest?
Tl;dr does one infrequent spawn of a nesting pokemon that changes species with each nest migration equal a nest?
To set this up, once I discovered TSR's near atlas, I checked it frequently, but no nests ever appeared in my town, and I had never found one. Until this however.
So I have a small park (roughly 2 square city blocks) within range of my house. It has one stop so I can basically see everything at the park from my couch whenever I choose. I started checking more frequently when I saw an Electabuzz there once a few months ago. I then saw another one the next day, and as I checked more often, more Electabuzz spawned. I figured it had to be a nest and I was thrilled that I found one! Turns out this may be the lamest "nest" in existence. The park basically has one cluster spawn point (2-6 mons at any given time) and that's it. I've noticed nesting pokemon, but rarely more than 1 at a time, never more than 2, and frequently none. Other than Electabuzz, I've seen Voltorb, Pinser, Jynx, Diglett, Pikachu, and other unusual for my biome pokemon. I check after migrations, but it usually takes me a couple days to figure it out because of the infrequent spawns. There are also some migrations where I recognize nothing, and all I can figure is that it turned into Ratata or Nidoran or something like that.
Anywho, would you guys consider this a nest, or is there another name for it?
Answers
Yup...a VERY small nest, but that is a nest all the same.
My nearest pokestop is the same - it has 2 spawn points that spawn basics, or a 'nesting' mon. It is usually very hard to tell what is exactly nesting as it is often just a basic common mon, but occassionally you can tell the nesting mon very easily (exactly as you described).
A couple of weeks ago it was Sneasel, so I actually bothered to go there a couple of times...and it made it easy to know what the nest was.
Migrating frequent spawns are exactly what a nest is. I don't think there is such thing as non-nest migrating frequent spawns other than during major game updates such as gen 2 release.
The unique characteristics of a nest are that there is only one nesting species at a time; participating spawn points spawn the nesting species 25% of the time; and the nesting species changes with the global nest migrations. It doesn't matter how big it is, if an area has these characteristics then it is a nest.
I have a very small park that is the same way. It has one Pokestop that spawns two to three Pokemon and the nest Pokemon at the time will spawn at the same point every time.
I also have a Pokestop that will act as a nest with a single nest spawn. Last migration I noticed something was up because I kept seeing Magmar on my nearby list multiple times per day.