I believe there's a logical fallacy for that:
The news prints these stories then they become the truth in the minds of many people.
Let's go with "hypothesis" for the sake of argument:
In this case, we have a basket of competing hypotheses, none of which have any solid evidence going for them.
Yet, some of these hypotheses have not been dismissed as conspiracy theories. Those were the hypotheses that conveniently fit a "humans encroach on wildlife"-narrative.
I'm just pointing this out as "interesting", I'm not arguing that this circumstance gives validity to one hypothesis over another.
So we have prior evidence...so we give more weight...
The investigators should examine all possibilities, of course.
Repeating the most “exciting” theory on Opinion News night after night...