Are shiny Remoraids, Octillery, and Poliwag found more often in X/Y than other Pokemon?

Question

In the GTS, there are a ton of shiny Pokémon, specifically those three. This couldn't be a hack so what is it?

Answer 1

They are from chain fishing, a new mechanic in X and Y that makes it more likely for you to find Shinys if you can get many Pokemon in a row with your fishing rod. Failing to find anything breaks the chain, as does moving from your position.

Comments

How many catches do you need for it to be shiny?

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It's really ambiguous, some get a shiny after four chains, some after four hundred.
Usually I get about 20 chains before I find my shiny, it's really all up to luck.