Why is fishing so hard outside of Cantha?

[Ordin.9047]

Every cast that I make is to a hard catch. 

[Redfeather.6401]

I heard the game scales even fishing stats down which makes fishing outside of level 80 zones bizarrely difficult.

[AgentMoore.9453]

The short answer is that Cantha is the 'starting area' for fishing, and everywhere else is meant to be more of a challenge once you get the basic idea of it.

The long answer is that outside of Cantha, fishing holes require more fishing power, a stat that can be raised by various foods, scrolls, and mastery buffs. Here's a wiki page on it with a table showing you all the various fishing power things you can have active at once and where you can get them.

I will caution that exotic fish in particular seem to be a little hokey right now, as higher fishing power almost seems to be making them harder to catch. Not sure what's up with that, but if you're just getting into fishing you shouldn't have to worry about them right away.