If the NY Times wrote an article claiming that Sergey Brin dumped raw sewage from his yacht, the responses would be based upon the assumption of accuracy of that story. If the story isn't accurate, it will quickly be corrected (and legal avenues should be exercised, such as libel lawsuits), which has to some degree happened in this case.
But what are people really supposed to do? For every story everyone must stay quiet? Let claims bake for a period? Put a disclaimer "If this story is accurate..." before every statement? That should be presumed.
In the end, though, while I had no comment on the original story (it seemed like a classic "they're rich...get 'em!" kind of story), I certainly don't find Parker a more reasonable chap after this 10,000 word outing. His argument is essentially-
a) Steelhead trout are stupid anyways. I'm humorously paraphrasing, but they are an endangered/threatened species, and you can't simply lump them in with Rainbow trout and pretend it's all good regardless.
b) Ignorance of the law is no defense. Saying that a group was formed before you were born makes one sound a bit like a jackass (maybe that's what the NSA is claiming? The various rights were written before they were born, so...)
c) He's good because he leveraged someone else's significant mismanagement of the forest, therefore he has no culpability. This is a bit of a tragedy of the commons thing, but his argument seems to be that all of this development happened in a vacuum and he just happened to be a sad passerby who might as well make use of it.
I don't think he needs to apologize to anyone, and it sounds like the land was horrendously mismanaged by the company that owns it, however this doesn't get sympathy.