Gator Bait
(1974)

Desiree (Claudia Jennings) is a voluptuous young Cajun lady, who lives deep in the swamp with her siblings.  The deputy, who is also the sheriff's son, wants to catch her poaching, in the hope that she will grant sexual favors rather than go to jail.  However, as the deputy and his friend Ben pursue her, the deputy accidentally shoots Ben.  The deputy lies, and says that Desiree shot Ben in cold blood.  The sheriff recruits Ben's father and two brothers to go into the swamp after Desiree.  They find Desiree's sister, Julie.  The brothers rape and kill Julie.

Desiree seeks revenge.  First, she kills the simple minded brother Pete, with a knife.  She shoots the deputy, but does not kill him.  Since he is dying, he reveals the truth, that he shot Ben.  This leads to a big bare knuckle brawl between his father (the sheriff) and Ben's father.  Ben's father kills the sheriff.  Ben's father and surviving brother leave the deputy bleeding in the swamp, and we see the gators moving in for the kill.  Desiree sets a trap for the second brother, Leroy.  Leroy avoids it and captures her.  It looks like she is doomed, but her little brother shoots and kills Leroy.

Finally, Desiree and her brother confront the last survivor, Ben's father.  He says for them to kill him, as with all his sons dead he has nothing to live for. Desiree instead leaves him deep in the swamp, with no boat, weapon or food, for the gators to kill.  

Thanks Joseph C!