Question

Which three words or phrases in this excerpt from Elizabeth Bishop's "The Fish" compare the fish to an old, experienced soldier?
A green line, frayed at the end
where he broke it, two heavier lines,
and a fine black thread
still crimped from the strain and snap
when it broke and he got away.
Like medals with their ribbons
frayed and wavering,
a five-haired beard of wisdom
trailing from his aching jaw.
I stared and stared
and victory filled up
the little rented boat,
from the pool of bilge
where oil had spread a rainbow