It's possible to catch a level 10 Salamence on the first island on Pokemon Sun and Moon! It's not at all easy and requires a lot of patience, but it can be done. You can watch a full video showing the process below...but here's a step by step guide in case you're in a rush or need a quick reference.

• Complete your first item trial against the Totem Gumshoe
• Progress game to second island and complete Malo's trial
• Get adrenaline orb from Poke Mart
• *Optional* get a Pokemon with the move "False Swipe" as it makes things easier
• Head over to Route 3 on MeleMele island
• Go down the wooden bridge and head right into a patch of grass
• Keep walking around in grass until you encounter Bagon. Bagon has a 1% encounter chance in this area so be patient!

Once you find one you use false swipe and wait for it to use the mechanic where it calls for help and another Pokemon comes to its aid. The chance of a Salamence showing up is very low as well so you'll have to keep burning turns and defeating Bagon's until it finally shows up!

It sounds made up I know, but there's video to confirm it! I'm not so sure it's worth the effort, but it's good to know if you're looking to get a Salamence early game! Thanks Arrekz Gaming for putting in the hours and VG247 for the heads up!