Entire male staff misbehaves with female staff (few in number) knowingly, highest rank in the office is silent. What should female staff do?

if there is such kind of environment no employee can survive, it is good to leave and find other job.

They should collect facts, evidence and present the matter to the higher management or OD team. 

Sister Anna Mae Maitim has given good suggestion.

The following steps may be followed;

1. Find  out the root cause
2. A written report  to the higher Management will be submitted, proceeding for final outcome and pros & con
3. Names of all misbehaving staff will be including with some  sort of witness
4. After all of the above a commissioned will be formed to investigate and report
5. Finally, culprits should be punished.

make a report about the occurrence of the event to explain what happened

let the high ranking official know from the horses mouth. talk to hr manager and inform him/her what's going on then ask for the time frame of the action. after that time frame, if you really like your job, go and seek labor's advice.

Also, female should be open/brave enough to say if any action offended them. The reaction of the female or any person will always be the reason why action is being repeated or stopped. 

mmmmmmmmmmmmm try to find another job and recording video for that behavior then make share with all web site

Very big problem,

I think there is a big gap between male and female employee in many offices and in many communities especially in male societies but we can not separate males from females in the offices 

I think its easier to work with both male and female. It depends on the person who is working with both and should be flexible enough to work with male as well as female.

As a female, consider yourself stronger than a male staff and since you are having a small strength, it's enough to check out the offenders. Follow below methods that have been successful.

1) Pray to the Almighty to give you the strength and protect from offenders; start doing good deeds and avoid bad deeds;

2) Be Bold. Warn the offender(s) in writing with copy to your Superior / HR / Owners that all offensive moves are being watched and recorded, and the offenders would be definitely taken to task if the Management or Offenders don't stop this negative behaviour;

3) Consult female-protection NGOs, female-grievance lawyers and human rights organizations;

4) Search in Google on "how to get protection from male offenders at work";

5) Avoid contact with these offenders as much as possible since you will become out of focus as well as the Employer & Management might not help you in your career advancement once you start taking action. 

If the higher rank in the office is silent then female staff should leave the job immediately because they cannot survive in this  kind of culture for a long time.