56: Owsla Scripted by John Ruths and Newell Fisher. What is an Owsla? Without an Owsla, the ONLY structure in a warren would be the Chief Rabbit. Hazel became Chief Rabbit simply based on his personality. Woundwort got to be a Chief by killing the previous one, so by a hostile takeover.  Who knows how Cowslip got to be a Chief but one might guess it was simply because he was the most 'in charge'. The Chief can't do everything. And here is how the Owlsa is born. It'll be made up of rabbits who are strong enough, maybe big enough, maybe fast enough, and very likely brave enough to do what needs to be done. Adam's mentions, in his footnotes, that a good storyteller might find a place in an Owsla in some warrens. And definitely a seer such as Fiver. Anytime a group of rabbits form, an Owsla would probably more or less work themselves out. The four Owsla's of WD in order.   Sandleford's Owsla The Sandleford Owsla seems to be one that tolerates petty privileges for Owsla members. And this is what gives Hazel the notion of leaving even before Fiver's premonition. It also seems to help drive Bigwig away, an Owsla member. And, for that matter, Silver. But this Owsla is nowhere near as bad as that of  Efrafa. This changes in the 1978 film. When Captain Holly catches the group trying to leave Sandleford, it is worth paying attention to what he actually says. In the book, Holly is only concerned with the Owsla members Bigwig and Silver. He doesn't seem to be concerned with the rest of the group at all. But in the 1978 film the actions of the Owsla are far harsher. The group that tries to leave is larger than in the novel, seemingly including does and maybe even some kittens, and most of them are immediately rounded up. Captain Holly then intercepts the remaining bucks and tells them they are ALL under arrest. This is at 13:20. So the Sandleford Owsla of the film seems to be far more like that of Efrafa. The Warren of the Snares Owsla It seems that an ad hoc posse-like Owsla can be raised fairly effectively when needed in this warren, as in when Holly's party, escaping from Sandleford, have the bad luck to bump into them. It is this Owsla that is the only one in the book that kills a rabbit from Sandleford: the already sick Pimpernel. This is a warren where leadership and discipline has ceased to matter a long time ago and even their most dangerous actions are more motivated by their mass suicidal-delusion than any desire for self-protection. WD's Owsla Bigwig was the Chief of a "very free and easy Owsla" at the end of WD. The Owsla formed pretty early, with Bigwig as the charter member.  Silver and Buckthorn were the next members. In "Tales from WD" Hazel comments, at one point, "We're all in the Owsla, really". By the end of the novel we see that the elderly chief, Hazel-rah, has a sentry outside his burrow. This may indicate that the WD Owsla has become a little more formalised. Efrafa's Owsla This is the only Owsla in the book with more than one Captain, each in charge of a Mark, or wide-patrols. The implication of the name of the chief rabbit, GENERAL Woundwort, seems to be that he is also the head of the Owsla. Efrafa has another structure that is unique in the book: the Council and their 'Owslafa' or 'Council Police'. The Council take on some of the Chief Rabbit's roles. The differences between the two security bodies are that the Owslafa is mostly concerned with internal security.  The Owsla is mainly concerned with their own rabbits within each of the four marks. So an Owslafa member would never have to worry about going on Wide Patrol. On the other hand, a member of the Owsla would not be given prisoner escort duty. The council is not a representative body of each mark. In fact you could say it is more of a Civil Service. Conclusion The Owslas of WD run a spectrum of formality, from least to most formal, as follows: 

Snares

Watership Down

Sandleford

Efrafa