It's reasonably easy (not trivial, not impossible) to track the trades of hedge funds, since they do have to disclose their transactions. And some guys will even tell you! [1] [2] [3]

Why they make their decisions is another question.

[1]: https://www.bloomberg.com/gadfly/articles/2016-09-14/herbali...

[2]: http://etfdb.com/etfdb-category/hedge-fund/

[3]: https://whalewisdom.com/