Lots of visits through search engines with zero visits. How to fight?

Question

Search Engine Optimization

I paid attention to this recently, because. it has become really annoying. 50 or more visits per day through key queries from different search engines to the site and with zero visits. 70% of these visits are repeated. After looking at them by the metric, they all make accurate visits once every 1-2 days. New ones are constantly appearing, all the time different regions, and many different keywords for which I was really visible. Now the statistics of failures is 50% (it used to be less than 1%), many positions have fallen off. I began to catch and ban them manually through iptables, but this is not a panacea. It seems that some ill-wishers are trying to merge me ((Tell me, who knows how to deal with such ailments?
PS In the metric, I turned on a tougher filter of bots, before that there were even more of them ...

Answer 1

The simplest solution: you can put a STOP HOTLINK filter.

Answer 2

In the logs, who comes in? Bots or what kind of browsers are they disguised as?