"Pokemon Nests" are places in Pokemon Go that regularly spawn a specific type of Pokemon. Pokemon nests have been reported all around the globe, to the point that some online communities are gathering data to create a map that shows where all of these Pokemon nests are. This morning, Pokemon Go players noticed something different about their local Pokemon nests: they were now spitting out different Pokemon.

It appears that Niantic Labs has changed the algorithm or coding that decides which Pokemon spawn from different nests. The changes occured worldwide and appear to follow a set pattern. Basically, it looks like the nests now spawn the basic Pokemon immediately before it in the Pokedex. So, a Charmander nest now spawns Bulbasaur instead, and a nest that previously spawned Squirtle now spawns Charmander.

Because all of the nests shifted "down" one spot, it seems that there are no longer Dratini nests, which will make Dragonites significantly harder to get in Pokemon Go. Other Pokemon that don't have nests include Porygon, Chansey, Lapras, and Snorlax, although it seems they never had nests to begin with.

Below is a list of the changes compiled by /r/TheSilphRoad, a Reddit community that tracks data on Pokemon Go. The Pokemon on the left are what used to appear at the Pokemon nests and the Pokemon on the right is what appears now:

Abra - Growlithe

Bellsprout - Poliwag

Charmander - Bulbasaur

Clefairy - Nidoran♂

Cubone - Drowzee

Diglett - Paras

Doduo - Ponyta

Dratini - Eevee

Drowzee - Seel

Eevee - Magikarp

Electabuzz - Jynx

Gastly - Magnemite

Growlithe - Meowth

Geodude- Machop

Hitmonchan - Voltorb

Hitmonlee - Krabby

Jigglypuff - Vulpix

Jynx - Scyther

Krabby - Shellder

Machop - Growlithe

Magmar - Electabuzz

Magikarp - Pinsir

Magnamite - Geodude

Mankey - Meowth

Nidoran♀ - Sandshrew

Nidoran♂ - Nidoran♀

Oddish - Jigglypuff

Onix - Doduo

Pikachu - Ekans

Rhyhorn - Cubone

Pinsir - Magmar

Ponyta - Bellsprout

Sandshrew - Pikachu

Scyther - Staryu

Shellder - Slowpoke

Slowpoke - Tentacool

Squirtle - Charmander

Tangela - Cubone

Tauros - Magmar

Voltorb - Gastly

Vulpix - Clefairy

It's unknown if the mass Pokemon nest switch will be a regular occurrence or a one-time tweak. The timing curiously lines up with the end of the calendar month, so we'll have to see if a switch occurs at the end of next month too. The change hasn't affected normal spawning, so don't expect the Pidgeys that pop up in your neighborhood to be replaced by Bulbasaurs any time soon.