How nests work in-game

Specific real-life parks can turn into in-game nests. Nests are areas in which a specific Pokémon spawns more frequently.

Spawns

There’s a pool of Pokémon that are able to nest. It’s a set list of base-evolution Pokémon, that rarely ever changes permanently. However, there can be temporary changes. Those might happen for the majority of events that influence spawn pools.

An updated list of permanent nesting species can be found here

Each Spawnpoint in a nest has a chance of 25% to spawn the nesting Pokémon.

Migrations

Regular migrations occur every 2 weeks, Thursday at 01:00am UTC. A countdown to the next migration can be found here.

Apart from regular migrations, there’s also forced migrations. Those take place whenever a Mon species is added to or removed from the nesting species pool.

How Parks become Nests

As everything else map-related, Pogo takes its nest data from OpenStreetMap (OSM). In this case, that data is from April 4th 2018. A park requires a specific tag to become a nest.

To find nests, you can use this Overpass query

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