There are a few opinions on that.  It is against our fish regs to deposit fish offals in the water.
Some folks say bury - we don't like that and anyway for most of WCP you'd need dynamite once you're past the first 6 " of soil!
We recomend find a point well away from your campsite and anyone elses - small islands are good, some exposed shoreline area anyway.  Drop them on on rock and in no time they seem disappear.

In any case, please keep in mind the peole coming behind you, leave the area clean and safe for them.

A good question.

Doug