Carnivine in Pokemon GO is a regional Pokemon and can be difficult to capture for some. While Pokemon GO has made it easier to capture regional Pokemon through events or trading, there are a few pesky ones left.
Carnivine Pokemon GO: Where to Find Carnivine
Carnivine is a prickly Pokemon which habits marshy areas and the good news for players in the US, it is a North American regional. However, Carnivine mainly inhabits these places in the United States: Tenessee, Atlanta, North Carolina, South Carolina, Georgia, Alabama, Florida, and the Bahamas.
If you do not live in the US it is best to wait for a region swap to obtain this Pokemon instead of flying cross-country in order to catch it. Or you can find someone to trade for it.