Deerling locations — where to catch

In Paldea (Scarlet & Violet)

• Dalizapa Passage — Walk
• Glaseado Mountain — Walk
• Tagtree Thicket — Walk

In Blueberry Academy (Scarlet & Violet – The Indigo Disk)

• Polar Biome — Walk

Other games (3)

• Omega Ruby / Alpha Sapphire (Gen 6): Route 117
• Black 2 / White 2 (Gen 5): Unova Route 6, Unova Route 7
• Black / White (Gen 5): Dragonspiral Tower, Unova Route 6, Unova Route 7

Deerling — full Pokédex entry