I have peeled this off a question asked in the Tauranga thread. It deserves a thread of it's own.

The question is interesting because I see kingfish (and GTs) being very much large baitfish predators. In most cases you would be best advised to cast a large fly to either species.

I have had both kingfish and GTs reject small flies. With the GTs its usually one of those unexpected encounters during a bonefish hunt and all you have time for is to cast your small bonefish fly at it. Invariably they barely look at it. Interestingly though, brassy trevally of quite large size can be caught in exactly the same situation. It sort of highlights that 'big baitfish predator' category that kingfish and GTs sit in.

There are situations where kingfish will eat small flies and it is the only situation where I have seen kingfish feeding on fish larvae of any sort. This is generally on glassy calm mornings. The kings are observed 'rolling' on tiny baitfish on the surface. The feeding style can be quite unhurried and it can be difficult presenting a fly without disrupting the feeding pattern.

I have seen a big school of solid kings doing this out by Cape Brett. Most of the kings were sitting beneath the surface in a large slow-moving school. Fish would peel off in twos and threes in order to roll on the bait. Suffice to say I failed to hook any of them and quickly managed to upset their feeding focus.

I can't say I have ever witnessed kingfish feeding on tiny baitfish inshore.

Anyone?

How small is tiny?  The anchovies that turn up in Auckland aren't particularly big but the kingfish love them, though they tend to be schools of mainly rat kings up to 75cm. I use pretty small flies when they are feeding on those because they can be rather picky. Normally size 2 hooks with a clouser style fly made from blue over white or white over white SF blend. Total size +-10cm. Red or white dumbbell eyes seem to work.

the most common bait my auckland flats kings is  small [silver on sides, dark back]