Absolutely...bull trout juveniles. True, bull trout have more fan tail than forked but juveniles typically start with the shallow v as you see in the pics. Laker juvies...are for sure forked...right from parr to juvie to adult.
Another diagnostic..and one the takes them away from being splakes as well (by the way, Splake? really....who stocks splake any more...really, anywhere? THAT's a waste of tax payer money right there
..ahem...where were we...oh yeah) .
The leading edge of the pectoral and pelvic fins....is white. Lakers...don't have a leading edge colour. And if splake (which is SPeckled <brook> trout and LAKE trout), the leading edge is black then white (look at your brookie pics).
Another...head shape....bullet not pointed...diagnostic for both brookie and bulls (and Dollys and Arctic Char too, by the way). Strange, this diagnostic...as for much of the char family, blunt is it for juvies...EXCEPT Lakers
'Course, if I could cut em open, I could tell if they were hybrids also by counting pyloric ceaca....but thats for another day....
Bull trout...and as we say...no black, put it back (regarding the black leading edge)
King Joe Outa Here!
Oh and I meant to come back to this. Interestingly enough...your post title says it all...."Interesting ALPINE Fish". Until 1978, bull trout were thought to be 'just' mountain...or ALPINE Dolly Varden. Now, we know better (don't we?)...Dollies are NOT Bull Trout..and bulls are not splake...errr, I mean...Dollies.