caught mr.pinchy in terokkar forest (sketis area/Blackwind Lake) in a highland school. between the shatariskyguard camp and the first building where those eggs are in. (so u have the lake on your left)
my fishing skill was 345 + 100 fishing with a lure + 25 fishing of my fishingpole(fishingpole is from a quest in hinterlands), so was having a totall of 470 fishing when i caught mr.pinchy.
first try i got some mana and health pots.
second try he attacked me.
third try i got the crawdad pet :-)