Yes. However, I want to clarify that what I gave was an opinion, and you could get a different opinion from other people. I based that opinion on the general results of laboratory work, which show that juvenile salmon--in this case, mainly pink and chum salmon--become more resistant to sea lice the larger they get.
They're the smallest of the salmon. A chum salmon would be about a quarter of a gram when it comes out into the river, and a pink salmon maybe a fifth of a gram. They are very, very tiny. They don't have fully developed scales when they first arrive in salt water, so they're quite vulnerable; at least, that's the conclusion that a lot of researchers have come to.
As they grow older, they get a more complex integument and start developing scales and perhaps other immune responses, because fish have an increasing immune response as they get larger. For any number of those reasons, they seem to become more resistant.
Sockeye salmon are smolts. They've already spent a full year in a lake, and in some cases two years, and they're much larger. They are 25 to 30 times larger than a pink fry and they have fully developed scales; therefore, I would suspect them not to be particularly vulnerable to sea lice.
Now, I don't know that anyone has done work with sockeye to prove this, so it's a bit of a conjecture, but I thought that of all the many things that could be affecting sockeye salmon populations in the Fraser, sea lice are perhaps the least likely.
That's my opinion. You might want to get another opinion from some of the DFO scientists.